Applied sciences

Archives of Metallurgy and Materials

Content

Archives of Metallurgy and Materials | 2023 | vol. 68 | No 1

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Abstract

To study the anti-seismic performance of steel structure under high temperature, the finite element analysis software ABAQUS was used to study the seismic performance of Q235 steel welded box section column at service stage under normal temperature and high temperature fire. The effects of welding residual stress, slenderness ratio, width thickness ratio and axial load level on the hysteretic behavior of columns were analyzed and the stable bearing capacity and hysteretic performance of the column under high temperature were investigated. The results show that the maximum bearing capacity of the column decreases with the increase of the residual stress peak value. With the increase of temperature, a decrease in the maximum bearing capacity of columns under constant axial force and horizontal cyclic load and an increase in the ductility occur.
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Authors and Affiliations

Yadi Fu
1
Xueyu Dai
2
Huidi Zhang
2
Yimin Wang
1

  1. Beijing Construction Engineering Group Co. Ltd, Beijing, China
  2. Department of Civil Engineering, China Agricultural University, Beijing, China
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Abstract

In the present research, we used molecular dynamics simulation to determine the effect of cutting parameters on micro-grain boundary structures and Burgers vector distribution in single crystal iron and polycrystalline iron materials. The result showed that the destruction of the lattice in polycrystalline iron caused by the cutting tool was restricted to the contact surface area. In addition, in the precision machining process, a higher refining grain was observed on the iron surface. During the cutting process of single crystal iron, large-scale slip occurred along the <111> crystal direction on the {110} crystal plane. And the slip presented an annular shape.
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Authors and Affiliations

Zhiming Liu
1
Qiang Zhang
2
Fangying Liu
2
Hezhe Zhang
2

  1. China University of Mining and Technology (Beijing), Beijing 100083, China
  2. Shandong University of Science and Technology, Qingdao 266590, Shandong, China
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Abstract

The numerical solutions of stress and strain components on the critical plane of tungsten carbide coating were solved based on the critical plane method in three-dimensional coordinate system, and accordingly three strain energy density parameters (Smith-Watson-Topper, Nita-Ogatta-Kuwabara and Chen parameters) were determined to reveal the fretting fatigue characteristics of tungsten carbide coating. In order to predict the fretting fatigue life based on the strain energy density criterion, the expressions between the strain energy density parameter and the fretting fatigue life was obtained experimentally. After the comparison of the three strain energy parameters, it was found that all three parameters could accurately predict the crack initiation position, but only the Smith-Watson-Topper parameters could accurately predict the crack initiation angle. The effects of cyclic load, normal load and friction coefficient on fretting fatigue damage behaviors were discussed by using the Smith-Watson-Topper criterion. The results show that the fretting fatigue life decreases with the increase of cyclic load; an increase in the normal contact load will cause the Smith-Watson-Topper damage parameters more concentrated at the outer edge of the bridge foot; a decrease in the friction coefficient will increase the Smith-Watson-Topper damage parameters in the middle of the contact surface.
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Authors and Affiliations

Xin Zeng
1 2
Xiaoxiao Wang
1 2
Xuecheng Ping
1 2
Renjie Wang
1 2
Tao Hu
3

  1. Tianjin University of Science and Technology, School of Mechanical Engineering, Tianjin 300222, China
  2. Tianjin University of Science and Technology, Tianjin Key Laboratory of Integrated Design and Online Monitoring of Light Industry and Food Engineering Machinery and Equipment, Tianjin 300222, China
  3. Shanghai Xifa Business Consult ing Co., Ltd., Shanghai 200232, China
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Abstract

This study aimed to prepare Zr55Cu30Al10Ni5 bulk amorphous alloys by spark plasma sintering of raw amorphous alloy powders and investigate their microstructure and micromechanical behaviors. When the sintering temperature ( Ts) was 675K, which was lower than the glass transition temperature ( Tg) of the material, the sintered sample was almost fully amorphous but the density was lower. However, when Ts was 705K, which was higher than Tg, partial crystallization occurred, but the density was higher. The hardness of the bonding zone of the sintered sample at 675K was 5.291 GPa due to the lower density, which was lower than that at 705K, and the hardness at 705K was 8.836 GPa. The generation of thermodynamically stable intermetallic phases, the hardness, and the elastic modulus of the samples sintered above Tg were higher due to the higher density.
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Authors and Affiliations

Yaqiong Ge
1
Zexin Chang
1
Wenxian Wang
1
Qingling Hou
1

  1. Taiyuan University of Science and Technology, College of Materials Science and Engineering, Taiyuan 030024, China
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Abstract

Surface coating technology, as the main technology to improve the fatigue life of mechanical systems, has been well applied in mechanical equipment. The present study aimed to explore low-cost surface coating preparation technology using inexpensive rice husk as the research object, and the pyrolysis process behavior of rice husk was analyzed. The Ni60/SiO 2 coating was prepared on the surface of the 45# steel substrate using the pyrolysis product SiO 2 fiber as the reinforcing phase and supersonic plasma-spraying equipment. The results showed no defects such as cracks, pores, and inclusions in the prepared coating. The nanohardness of the Ni60/SiO 2 coating reached 6506 μN, and the average friction coefficient reached 0.42. In the friction-and-wear experiment, the Ni60/SiO 2 coating was manifested as an abrasive wear mechanism.
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Authors and Affiliations

Chunxue Wei
1
Hongbing Li
1

  1. Henan Light Industry Vocational College, Zhengzhou, 450002, P.R. China
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Abstract

Directed energy deposition (DED) is an additive manufacturing process wherein an energy source is focused on a substrate on which a feedstock material is simultaneously delivered, thereby forming a small melt pool. Melting, solidification, and subsequent cooling occur at high rates with considerable thermal gradients compared with traditional metallurgical processes. Hence, it is important to examine the effects of cooling rates on the microstructures and properties of the additive manufactured materials. In this study, after performing DED with various energy densities, we investigated the changes in the microstructures and Vickers hardness of cast Al-33 wt.% Cu alloy, which is widely used to estimate the cooling rate during processing by measuring the lamellar spacing of the microstructure after solidification. The effects of the energy density on the cooling rate and resultant mechanical properties are discussed, which suggests a simple way to estimate the cooling rate indirectly. This study corresponds to the basic stage of the current study, and will continue to apply DED in the future.
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Authors and Affiliations

Yeon-Joo Lee
1 2
ORCID: ORCID
Do-Hun Kwon
1
ORCID: ORCID
Eun-Ji Cha
1
ORCID: ORCID
Yong-Wook Song
2
ORCID: ORCID
Hyun-Joo Choi
2
ORCID: ORCID
Hwi-Jun Kim
1
ORCID: ORCID

  1. Korea Institute of Industrial Technology, Research Institute of Advanced Manufacturing & Materials Technology, 156, Gaetbeol-ro, Yeonsu-gu, Incheon, Republic of Korea 21999
  2. Kookmin University Dept. of Advanced Materials Engineering, Seoul, KS013, Republic of Korea
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Abstract

In this study, the effects of heat-treatment conditions of Fe powder compacts on densification, microstructure, strength and magnetic properties were investigated. The prepared Fe powder was compressed in a mold of diameter 20 mm at a pressure of 800 MPa for 30 sec. This Fe powder compact was heat-treated under different atmospheres (air and 90% Ar + 10% H2 and heat-treatment temperatures (300 and 700℃). The Fe powder compacts heat-treated in an Ar+H2 mixed gas atmosphere showed a denser microstructure and higher density than the Fe powder compacts heat-treated in an air atmosphere. Oxygen content in the heat-treatment conditions played a significant role in the improvement of the densification and magnetic properties.
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Authors and Affiliations

Hyo-Sang Yoo
1
ORCID: ORCID
Yong-Ho Kim
1
ORCID: ORCID
Cheol-Woo Kim
1
ORCID: ORCID
Hyeon-Taek Son
1
ORCID: ORCID

  1. Korea Institute of Industrial Technology, Automotive Materials & Components R&D Group, 1110-9 Oryong-dong, Buk-gu, Gwangju 61012, Republic of Korea
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Abstract

Fixed beds were adopted for removal of organic dye from water by photocatalytic decomposition or adsorption. To this end, macroporous titania or silica micro-particles were synthesized from emulsions as micro-reactors and packed in the bed. During feeding aqueous methylene blue solution, UV light was irradiated for generation of active radicals for removal of dye by photocatalytic decomposition. Porous silica particles were also used as adsorbents in the bed for continuous adsorption of organic dye. For regeneration of the porous titania or silica particles, rinsing with fresh water was carried out before repeated cycles.
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Authors and Affiliations

Young-Sang Cho
1
ORCID: ORCID
Sohyeon Sung
1
ORCID: ORCID

  1. Tech University of Korea, Department of Chemical Engineering and Biotechnology, 15073, 237 Sangidaehak-ro, Siheung-si, Korea
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Abstract

The paper presents a summary of research on the possibility of influencing the state of residual stresses in railway rails by changing the pass design of vertical and horizontal straightener rollers and optimising their distribution on the rail perimeter. The presented results are devoted to the influence of profiled rollers on the level of residual stresses. A wide range of theoretical considerations were carried out based on the use of the finite element method using the commercial Forge software package. In order to verify the results of the theoretical considerations most reliably, a series of “in situ” experiments were conducted in industrial conditions on an existing production line. The tests were carried out on 120 meters long 60E1 railway rails. A significant reduction in the level of residual stresses compared to the standard requirements was achieved.
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Authors and Affiliations

S. Żak
1
ORCID: ORCID
D. Woźniak
2
ORCID: ORCID

  1. ArcelorMittal Poland S.A., Al. Józefa Piłsudskiego 92, 41-300 Dąbrowa Górnicza, Poland
  2. Institute for Ferrous Metallurgy, ul. Karola Miarki 12, 44-100 Gliwice, Poland
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Abstract

Cu-Sn alloys have been known as bronze since ancient times and widely used as electrode materials, ornaments, tableware and musical instruments. Cu-22Sn alloy fabrication by hot forging process is a Korean traditional forged high-tin bronze. The tin content is 22 percent, which is more than twice that of bronze ware traditionally used in China and the West. Copper and tin have a carbon solubility of several ppm at room temperature, making Cu-Sn-C alloys difficult to manufacture by conventional casting methods. Research on the production of carbon-added copper alloys has used a manufacturing method that is different from the conventional casting method. In this study, Cu-22Sn-xC alloy was fabricated by mechanical alloying and spark plasma sintering. The carbon solubility was confirmed in Cu-Sn alloy through mechanical alloying. The lattice parameter increased from A0 to C2, and then decreased from C4. The microstructural characteristics of sintered alloys were determined using X-ray diffraction and microscopic analysis. As a result of comparing the hardness of Cu-22Sn alloys manufactured by conventional rolling, casting, and forging and Cu-22Sn-xC alloy by sintered powder metallugy, B0 sintered alloy was the highest at about 110.9 HRB.
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Authors and Affiliations

Gwanghun Kim
1
ORCID: ORCID
Jungbin Park
1
ORCID: ORCID
Seok-Jae Lee
1
ORCID: ORCID
Hee-Soo Kim
2
ORCID: ORCID

  1. Jeonbuk National University, Division of Advanced Materials Engineering, 567 Baekje-daero, Deokjin-gu, Jeonju 54896, Republic of Korea
  2. Chosun University, Department of Materials Science and Engineering, 309 Pilmun-daero, Dong-gu, Gwangju 61452, Republic of Korea
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Abstract

The austenitic stability and strain-induced martensitic transformation behavior of a nanocrystalline FeNiCrMoC alloy were investigated. The alloy was fabricated by high-energy ball milling and spark plasma sintering. The phase fraction and grain size were measured using X-ray diffraction. The grain sizes of the milled powder and the sintered alloy were confirmed to be on the order of several nanometers. The variation in the austenite fraction according to compressive deformation was measured, and the austenite stability and strain-induced martensitic transformation behavior were calculated. The hardness was measured to evaluate the mechanical properties according to compression deformation, which confirmed that the hardness increased to 64.03 HRC when compressed up to 30%.
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Authors and Affiliations

Jungbin Park
1
ORCID: ORCID
Junhyub Jeon
1
ORCID: ORCID
Namhyuk Seo
1
ORCID: ORCID
Gwanghun Kim
1
ORCID: ORCID
Seung Bae Son
1
ORCID: ORCID
Jae-Gil Jung
1
ORCID: ORCID
Seok-Jae Lee
1
ORCID: ORCID

  1. Jeonbuk National University, Research Center for Advanced Materials Development, Division of Advanced Materials Engineering, Jeonju 54896, Republic of Korea
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Abstract

The effects of different types of balls on spark plasma sintering (SPS) characteristics of high energy ball milled Ti-48wt% Al-4wt% Nd powders were investigated. After ball milling with STS balls and zirconia balls at 800 rpm for 3 h in argon atmosphere, both powders showed shape factors of about 0.8, but their average powder sizes differed respectively at approximately 11 µm and 5 µm. From XRD results, only the peaks of pure Ti, Al and Nd were detected in both powders. The obtained Ti-Al-Nd powders were consolidated by SPS technique at 1373 K for 15 min under a pressure of 50 MPa in vacuum, resulting in high density over 99%. EDS and XRD analyses indicated the formation of binary phases such as TiAl3, TiAl, Ti3Al5, and NdAl3 after SPS in both cases of STS and zirconia balls, while the ternary Ti-Al-Nd phase was detected only in the case of zirconia balls. The size of second phases was slightly smaller in the case of zirconia balls. The microhardness of the sample was 790 Hv with zirconia balls and 540 Hv with STS balls.
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Authors and Affiliations

Hyunseung Lee
1
ORCID: ORCID
Hoseong Rhee
1
ORCID: ORCID
Sangsoo Lee
2
ORCID: ORCID
Si Young Chang
1
ORCID: ORCID

  1. Korea Aerospace University, Department of Materials Science and Engineering, Goyang, Korea
  2. Korea Aerospace University, Advanced Materials Research Institute, Goyang, Korea
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Abstract

In present study, Fe-22Cr-4.5Al oxide dispersion strengthened ferritic alloys were fabricated using a pre-alloyed powder with different minor alloying elements, and their microstructures and tensile properties were investigated to develop the advanced structural materials for high temperature service components. Planetary-typed mechanical alloying and uniaxial hot pressing processes were employed to fabricate the Fe-Cr-Al oxide dispersion strengthened ferritic alloys. Microstructural observation revealed that oxide dispersion strengthened ferritic alloys with Ti, Zr additions presented extremely fine micro-grains with a high number density of nano-scaled oxide particles which uniformly distributed in micro-grains and on the grain boundaries. These oxide particles were confirmed as a fine complex oxide, Y2Zr2O7. These favorable microstructures led to superior tensile properties than commercial ferritic stainless steel and oxide dispersion strengthened ferritic alloy with only Ti addition at elevated temperature.
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Authors and Affiliations

Minha Park
1
ORCID: ORCID
Jaeyoon Bae
2
ORCID: ORCID
Byung Jun Kim
1
ORCID: ORCID
Bu-An Kim
2
ORCID: ORCID
Sanghoon Noh
2
ORCID: ORCID

  1. Korea Institute of Industrial Technology, Dongnam Regional Division, Busan, 46938, Korea
  2. Pukyong National University, Department of Materials Science and Engineering, Busan, 48513, Korea
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Abstract

In this study, the effect of calcium treatment on the mechanical properties and fatigue behavior of low carbon steel material is investigated. By applying calcium treatment after aluminum deoxidation for steel cleanliness, the aim is to transform the inclusions into harmless structures and produce cleaner liquid steel. As a result of the study, calcium treated material’s tensile strength slightly increases while fatigue life decreases. SEM studies were conducted to evaluate the results and it was observed that while elongated inclusions were observed as well as spherical shapes in the untreated sample, the inclusions generally had a spherical shape in the calcium treated sample. After the steel cleanliness process, the mechanical properties of the samples were improved. The tensile strength of the calcium treated sample increased slightly. However, a significant decrease in fatigue strength was observed depending on brittle inclusions that occur as a result of the calcium treatment process.
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Authors and Affiliations

Barış Karabayrak
1
ORCID: ORCID
Sinem Baskut
2
ORCID: ORCID
Dilek Turan
1
ORCID: ORCID

  1. Eskisehir Technical University, Faculty of Aeronautics and Astronautics, Department of Airframe and Power Plant Maintenance, Eskisehir, Turkey
  2. Eskisehir Technical University, Faculty of Engineering, Department of Materials Science and Engineering, Eskisehir, Turkey
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Abstract

The forming limit of AZ31 alloy, a representative Mg-Al-Zn-based wrought alloy, and the effect of severe plastic deformation (SPD) by examining the microstructure change caused by dynamic recrystallization led by high temperature and high dislocation density at 300℃ using a biaxial alternate forging (BAF) were investigated in this study. As a result of BAF test for AZ31 Mg alloy, significant cracks on the ends of workpieces occurred after 7 passes. The microstructure of as-extruded specimen showed the non-uniform distribution of the relatively coarse grains and the fine grains considered to be sub-grains. However, as the number of passes increases, the area of coarse grains gradually disappeared and the fine grains became more dominant in the microstructures. The result of tensile test for workpieces with each forging pass showed an increase in strength depending on pass number was shown with a slight increase of elongation. The Electron Backscatter Diffraction (EBSD) results exhibited that, the microstructure showed the presence of coarse grains and twins after only 1 pass, while the grains appeared to be significantly refined and uniformly distributed after 3 pass, at which the strength and elongation began to increase, simultaneously.
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Authors and Affiliations

Young-Chul Shin
1
ORCID: ORCID
Seong-Ho Ha
1
ORCID: ORCID
Abdul Wahid Shah
1
ORCID: ORCID

  1. Korea Institute of Industrial Technology (KITECH), Molding & Metal Forming R&D Department, 156 Gaetbeol-ro, Yeonsu-gu, Incheon 21999, Republic of Korea
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Abstract

In this study, a rare earth composite precipitation (NaREE(SO 4) 2H 2O, REE: Ce, La, Nd, Pr) powder was prepared from spent nickel hydride batteries, and cerium hydroxide was separated from its constituent rare earth elements. As Ce(OH) 3 can be oxidized more easily than other rare earth elements (La, Nd, and Pr), Ce 3+ was converted to Ce 4+ by injecting air into the leachate at 80°C for 4 h. The oxidized powder was leached using sulfuric and hydrochloric acids. Because Ce(OH) 4 has low solubility, it can be separated from other elements. Therefore, the pH of the leaching solution was adjusted for selective precipitation. To determine the crystalline phase, recovery, and grade of the recovered Ce(OH) 4, the powders were analyzed using X-ray diffraction, scanning electron microscopy, and inductively coupled plasma optical emission spectroscopy. The grade and recovery rates of the Ce(OH) 4 powder recovered from the rare earth composite precipitate using sulfuric acid as the solvent were 95% and 97%, respectively, whereas those of the powder recovered using hydrochloric acid were 96% and 95%, respectively.
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Authors and Affiliations

Boram Kim
1
ORCID: ORCID
Dae-Weon Kim
1
ORCID: ORCID
Hee Lack Choi
2
ORCID: ORCID

  1. Institute for Advanced Engineering, Advanced Material & Processing Center, 175-28 Goan-ro, 51 Beon-gil, Yongin-si, Gyeonggi, 17180, Korea
  2. Pukyong National University, Department of Material Science & Engineering, 45, Yongso-ro, Nam-gu, Busan, 48513, Republic of Korea
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Abstract

CM247LC alloy was manufactured by using selective laser melting (SLM) process, one of the laser powder bed fusion ­(L-PBF) methods. The hot isostatic pressing (HIP) process was additionally conducted on the SLM-built CM247LC to control its microstructures and defects. The high temperature oxidation property was investigated, and it was compared with conventional DS247LC sample (reference) prepared via the directional solidification process. The L-PBF HIP sample showed blocky-type MC carbides generated along the grain boundary with average size of about 200 nm. A semi-spherical primary γ' phase of size 0.4-1.0 μm was also observed inside the grains. Moreover, the DS247LC sample displayed a coarse eutectic γ' phase and many script-type MC carbides. Furthermore, cuboidal-type γ' with an average size of about 0.5 μm was detected. High-temperature oxidation tests were conducted at 1000°C and 1100°C for 24 hours. The results at 1100°C oxidation temperature showed that the measured oxidation weight gains for HIP and DS247LC were 1.96 mg/cm2 and 2.26 mg/cm2, respectively, indicating the superior high-temperature oxidation resistance of the L-PBF HIP sample. Based on the above results, a high-temperature oxidation mechanism of the CM247LC alloys manufactured by the SLM process and the directional solidification process has been proposed.
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Authors and Affiliations

Jung-Uk Lee
1
Young-Kyun Kim
2
ORCID: ORCID
Seong-Moon Seo
2
Kee-Ahn Lee
1
ORCID: ORCID

  1. Inha University, Department of Materials Science and Engineering, Incheon 22212, Republic of Korea
  2. Korea Institute of Materials Science, Changwon 51508, Republic of Korea
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Abstract

The lap joint welding of Al 3003 alloy by stationary shoulder friction stir welding (SSFSW) was performed under the conditions of tool rotation and welding speed, and it was confirmed that the welding was performed under all conditions. The tunnel defects and pores were formed in the weld zone at the lowest tool rotation and welding speed, and it is increased, the weld surface has been improved. At the same tool rotation speed at the welding speed is increased, the grain size was refined in the stir zone (SZ) and thus the hardness increased by about 14% compared to the base metal. The tensile shear strength is measured to be 10 kN or more under most conditions, and in the 4000 rpm with high heat input, the shear tensile strength was measured relatively lower than other conditions due to excessive heat input of the material.
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Authors and Affiliations

Woo-Chul Jung
1
ORCID: ORCID
Joo-Heon Park
1
Sang-Min Yoon
1
Young Kyun Kim
1

  1. Advanced Material & Processing Center, Institute for Advanced Engineering, 175-28 Goan-ro, 51 beon-gil, Yongin-si, Gyeonggi, 17180, Korea
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Abstract

This study investigated the effect of heat treatment on the microstructure and impact toughness property of AISI D2 manufactured with direct energy deposition (DED) and compared the results with conventional wrought material. The fracture crack propagation behavior was examined in connection with microstructures through fracture surface analysis. AISI D2 manufactured with DED had a eutectic structure that turned into a net-type carbide after heat treatment, and Cr-rich needle-type secondary carbide was observed. Impact toughness of DED AISI D2 measured 2.0 J/cm2 in the as-built sample and 1.1 J/cm2 in the heat-treated sample. Compared to a wrought heat-treated AISI D2, DED AISI D2 had relatively low impact toughness. DED AISI D2 and wrought material had different crack propagation mechanisms. In DED AISI D2, the eutectic structure and net-type carbide boundary were identified as the major microstructural factor decreasing impact toughness.
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Authors and Affiliations

Jung-Hyun Park
1
ORCID: ORCID
Kyu-Sik Kim
1
ORCID: ORCID
Yong-Mo Koo
2
ORCID: ORCID
Jin-Young Kim
3
ORCID: ORCID
Min-Chul Kim
4
Kee-Ahn Lee
1
ORCID: ORCID

  1. Inha University, Department of Materials Science and Engineering, Incheon 22212, Korea
  2. Changsung Corp., Incheon, 21628, Korea
  3. Maxrotech Corp., Daegu, 42703, Korea
  4. Korea Atomic Energy Research Institute (KAERI), Daejeon 34057, Korea
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Abstract

This study was conducted to treat radioactive acidic wastewater, which contained radioactive 60Co and 152Eu. The wastewater can be generated during a decommissioning project to reduce the volume of radioactive concrete waste from nuclear facilities. With a variety of methods for separating the radioactive nuclides available, we evaluated the separation applicability of the solvent extraction method. From our results, Co and Eu could be easily extracted from the Ca rich wastewater using Cyanex301 (Co extraction (%) 99.8, Eu extraction (%) 99.6) without Ca extraction. On the other hand, Eu could be selectively separated by Cyanex272 (Eu extraction (%) 99.1) without Co and Ca extraction at pH 2~3. Therefore, the extraction method can be tailored according to the target radionuclides present in the wastewater and be selectively applied to the overall treatment process. By extracting radioactive Co and Eu from acidic wastewater to below the discharge criteria, treated wastewater could be regarded as non-radioactive industrial waste, to be economically and easily handled. Moreover, it may be possible to reuse separated Co and Eu for research and industrial applications by realizing waste valorization.
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Authors and Affiliations

Maengkyo Oh
1 2
ORCID: ORCID
Keunyoung Lee
1
ORCID: ORCID
Richard I. Foster
1 3
ORCID: ORCID
Ik-Soo Kim
1
ORCID: ORCID
Chang-Ha Lee
2
ORCID: ORCID

  1. Korea Atomic Energy Research Institute (KAERI), Decommissioning Technology Research Division, 111, Daedeok-Daero 989 Beon-Gil, Yuseong-Gu, Daejeon, 34057, Republic of Korea
  2. Yonsei University, Department of Chemical and Biomolecular Engineering, 50 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
  3. Seoul National University, Nuclear Research Institute for Future Technology and Policy, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
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Abstract

A TiC-Mo 2C-WC-Ni alloy cermet was fabricated by high-energy ball milling (HEBM) and consolidation through spark plasma sintering. The TiC-based powders were synthesized with different milling times (6, 12, 24, and 48 h) and subsequently consolidated by rapid sintering at 1300°C and a load of 60 MPa. An increase in the HEBM time led to improved sinterability as there was a sufficient driving force between the particles during densification. Core-rim structures such as (Ti, W)C and (Ti, Mo)C (rim) were formed by Ostwald ripening while inhibiting the coarsening of the TiC (core) grains. The TiC grains became refined (2.57 to 0.47 µm), with evenly distributed rims. This led to improved fracture toughness (11.1 to 14.8 MPa·m 1/2) owing to crack deflection, and the crack propagation resistance was enhanced by mitigating intergranular fractures around the TiC core.
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Authors and Affiliations

Jeong-Han Lee
1
ORCID: ORCID
Jae-Cheol Park
1
ORCID: ORCID
Hyun-Kuk Park
1
ORCID: ORCID

  1. Automotive Materials & Component R&D Group, Korea Institute of Industrial Technology, 6, Cheomdan-gwagiro 208-gil, Buk-gu, Gwangju, 61012, Korea
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Abstract

Fusion welding of Ti-Cu is difficult because of big difference of melting points and formation of brittle intermetallic compounds. Friction stir welding is carried out by solid-state joining, thermo-mechanical stirring, and friction heat. Ti-Cu FSW dissimilar welding can supply a very sound joint area with a few intermetallic compounds. Optimized welding process conditions are essential to obtain suitable microstructure and mechanical properties of welded zones. Different welding speeds affect the evolution of microstructure and mechanical properties due to changes of input heat and internal stored deformation energy. The correlation of microstructure and mechanical properties of Ti-Cu welded zone according to welding speeds were investigated and analyzed. As the higher the welding speed, the lower the heat input and the lower the temperature rise. Ti-Cu 75 has the smallest grain size at 13.9 μm, but the optimum mechanical properties and the integrity of welding were shown in Ti-Cu 50.
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Authors and Affiliations

Yong-Jae Lee
1
ORCID: ORCID
Won-Ki Jeong
1
Seung-Jun Lee
2
Hidetoshi Fujii
3
Se Eun Shin
1
Dong-Geun Lee
1
ORCID: ORCID

  1. Sunchon National University, Department of Materials Science and Metallurgical Engineering, Suncheon, 57922, Republic of Korea
  2. Korea Polytechnic University, Department of Advanced Materials Engineering, Siheung, 15073, Republic of Korea
  3. Osaka University, Joining and Welding Research Institute, Osaka 567-0047, Japan
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Abstract

This study aimed to develop Fe/Al multilayered metallic/intermetallic composites produced by hot pressing under an air atmosphere. Analyses were carried out on the composite plates made up of alternatively situated sheets of AA1050 aluminum alloy and DN04 low carbon steel, which were annealed at 903 K for 2, 5, and 10 h. Annealing was performed to obtain reaction layers of distinct thickness. The samples were examined using X-Ray diffraction and scanning and transmission electron microscope equipped with an energy-dispersive X-Ray spectrometer. To correlate the structural changes with mechanical properties, microhardness measurements in near-the-interface layers were performed. All the reaction layers grew with parabolic kinetics with η-Al5Fe2 intermetallic phase as the dominant component. After annealing for 5 and 10 hours, a thin sublayer of θ-Al13Fe4 phase was also detected.
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Authors and Affiliations

W. Kowalski
1
ORCID: ORCID
H. Paul
1
ORCID: ORCID
I. Mania
1
ORCID: ORCID
P. Petrzak
1
ORCID: ORCID
P. Czaja
1
ORCID: ORCID
R. Chulist
1
ORCID: ORCID
A. Góral
1
ORCID: ORCID
M. Szlezynger
1
ORCID: ORCID

  1. Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta Str., 30-059 Krakow, Poland
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Abstract

The mechanical response of interpenetrating co-continuous composite Al-Si12/SiC3D was described for uniaxial tension and compression. The internal structure of the IPC was examined by optical microscopy and micro-CT. The apparent density and Young’s modulus were assessed theoretically and experimentally. Uniaxial tensile tests were performed using the prismatic samples of dimensions 1 mm × 2 mm × 30 mm. Cylindrical samples of diameters ϕ = 5 mm and height h = 10 mm were subjected to quasi-static uniaxial compressive loading. During tests, the side surfaces of the specimen were observed using a digital image correlation system (DIC) to find strain fields and to monitor the surface cracks development in the complex internal microstructure of the IPC.
The analyzed two-phase ICP was manufactured using ceramic foam SiC infiltrated by alloy Al-Si12. This material finds application in cosmic, airplane, or automobile industries, due to their excellent tribological, heat distribution, and ballistic properties.
Obtained results show different modes of microcracking and fracture of cylindrical and prismatic samples. They indicate the substantial influence of the ceramic skeleton on the behavior of the IPC under uniaxial states of loading. Different modes of damage related to the tension or compression loading were described in detail. The results can find application in the designing process of modern co-continuous IPCs and further development of the numerical models of degradation processes.
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Authors and Affiliations

D. Pietras
1
T. Sadowski
1
M. Boniecki
2
E. Postek
3

  1. Lublin University of Technology, 20-618 Lublin, 38D Nadbystrzycka Str., Poland
  2. Łukasiewicz Research Network, Institute of Microelectronics and Photonics , 02-668 Warsaw, Poland
  3. Institute of Fundamental Technological Research, Polish Academy of Sciences, 02-106 Warsaw, Poland
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Abstract

A Si-Fe-Al ternary oxide-based micropowder coating was used to prevent the formation of a Zn coating on steel during the hot-dip Zn galvanizing process to reduce the welding fume and defects generated during the welding of Zn-galvanized steel. The composition ratio of the oxide powder was optimized and its microstructure and weldability were evaluated. The optimized oxide coating was stable in the hot-dip galvanizing bath at 470°C and effectively inhibited the formation of Zn coating. The Zn residue could be easily removed with simple mechanical impact. The proposed coating reduced Zn fume and prevented the residual Zn from melting in the weld bead during high-temperature welding, thus reducing the number of welding defects. The results indicated that this pretreatment can simplify the manufacturing process and shorten the process time cost-effectively.
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Authors and Affiliations

Seong-Min So
1
Ki-Yeon Kim
1
Il-Song Park
1
ORCID: ORCID
Seok-Jae Lee
1
ORCID: ORCID
Dong-Jin Yoo
2
Yeon-Won Kim
3
ORCID: ORCID
Min-Suk Oh
1
ORCID: ORCID

  1. Jeonbuk National University, Division of Advanced Materials Engineering, Jeonju, Republic of Korea
  2. Jeonbuk National University, Department of Energy Storage/Conversion Engineering Of Graduate School, Department of Life Science, Hydrogen and Fuel Cell Research Center, Jeonju, Republic of Korea
  3. Mokpo National Maritime University, Division of Marine Mechatronics, Mokpo, Republic of Korea
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Abstract

Surface melting and alloying of Copper-Nickel (Cupronickel) alloy by preplacing aluminum powder and using tungsten inert gas process (TIG) in shielded atmosphere of argon gas were investigated. Surface melting resulted in the formation of a fairly porous dendritic microstructure. Surface alloying with aluminum resulted in the formation of Al 2Cu and Al 4Cu 9 intermetallic compounds along with Cu-rich matrix and unstable martensitic structure. Surface melting reduced the hardness from 140 HV 0.1 (substrate) to 70 HV 0.1, mainly due to the loss of cold work effect of the initial substrate. On the other hand, surface alloyed zone showed a hardness of 300 HV 0.1, mainly due to the formation of intermetallic compound. Tafel polarization results indicated improvement in corrosion resistance of cupronickel alloy after surface melting and alloying.
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Authors and Affiliations

Fatemeh Koeini
1
ORCID: ORCID
Mahmoud Heydarzadeh Sohi
1
ORCID: ORCID
Parham Pirayesh
2
ORCID: ORCID

  1. University of Tehran, College of Engineering, School of Metallurgy and Materials Engineering, Tehran, Iran
  2. Islamic Azad University, Faculty of Engineering, Department of Metallurgy and Materials, Karaj Branch, Karaj, Iran
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Abstract

An attempt has been made to synthesize the aluminium based ex-situ (Al-SiC) and in-situ (Al-TiB2) formed metal matrix composites with varying weight percentage of reinforcement contents such as 4wt.%, 6wt.% and 8wt.%. Synthesized composites were subjected to a cold extrusion process followed by heat treatment according to the ASTM B 918-01 standards. The mechanical properties of in-situ composites were evaluated as per the ASTM guidelines and compared with ex-situ formed composites and base metal properties. Superior properties were noticed in the in-situ formed composites and the mechanical properties such as yield strength, Ultimate tensile strength (UTS) and Hardness for both ex-situ and in-situ composites were found to increase with increasing the reinforcement addition. Cold extruded Al-8 wt.% SiC composite properties such as hardness, yield strength and UTS are 87 RB, 152 MPa, 216 MPa respectively. Whereas, for Al-8 wt.% TiB2 composite, the corresponding properties are 94 RB, 192 MPa, 293 MPa. The morphology of the composites is analysed by Optical and Scanning Electron Microscopic (SEM) whereas presence of reinforcement particles such SiC and TiB2 along with intermetallic phases Mg2Si and Al5FeSi are confirmed by EDX, XRD and Element Mapping analyses.
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Authors and Affiliations

B. Gobalakrishnan
1
C. Rajaravi
2
Gobikrishnan Udhayakumar
3
P.R. Lakshminarayanan
4

  1. CARE College of Engineering, Department of Mechanical Engineering, Trichy-620 009, Tamil Nadu, India
  2. Hindusthan College of Engineering and Technology, Coimbatore – 641 032, Tamilnadu, India
  3. Sona College of Technology, Department of Mechanical Engineering, Salem – 636 005, Tamil Nadu, India
  4. Annamalai University, Department of Manufacturing Engineering, Annamalai Nagar-608 002, Tamil Nadu, India
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Abstract

The effect of plasma-radical change on the surface properties of Zn-Mg-Al ternary-alloy-coated steel sheets during atmospheric-pressure (AP) plasma treatment using different process gases: O 2, N 2, and compressed air was investigated. The plasma-induced radicals promoted the formation of chemical particles on the surface of the Zn-Mg-Al coating, thereby increasing the surface roughness. The surface energy was calculated using the Owen-Wendtgeometric equation. Contact angle measurements indicated that the surface free energy of the alloy sheets increased upon AP plasma treatment. The surface properties of the Zn-Mg-Al coating changed more significantly in the order air > O 2 > N 2 gas, indicating that the plasma radicals facilitated the carbonization and hydroxylation of the Mg and Al components during the AP plasma treatment.
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Authors and Affiliations

Chang-U Jeong
1
Jae-Hyeon Kim
1
Je-Shin Park
1
ORCID: ORCID
Min-Su Kim
2
ORCID: ORCID
Sung-Jin Kim
3
ORCID: ORCID
Min-Suk Oh
1
ORCID: ORCID

  1. Jeonbuk National University, Division of Advanced Materials Engineering, Jeonju, Republic of Korea
  2. Korea Institute of Industrial Technology, Gimje, Republic of Korea
  3. Sunchon National University, Department of Advanced Materials Engineering, Sunchon, Republic of Korea
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Abstract

Impacts of precursor solution recipe, processing parameters, and pellet thickness on the lithium ionic conductivity of the ceramic materials with perovskite structure of Li 0.3La 0.57TiO 2 0.3La 0.57TiO 2 0.3La 0.57TiO 22 (i.e., TiO 2 sol) and then Li+ and La+ were added to the colloidal TiO 2 was on the order of 10-5 S/cm. It also showed that the temperatures corresponding to a full decomposition for Li 0.3La 0.57TiO 2 is about 750°C and materials start forming perovskite structure when temperature reaches about 900°C and the lithium ionic conductivity gains about 21% increase when the pellet thickness is reduced to about ¼.
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Authors and Affiliations

C.K. Rhee
1
ORCID: ORCID
Y.B. Chun
1
ORCID: ORCID
S.H. Kang
1
ORCID: ORCID
W.W. Kim
1
ORCID: ORCID
G. Cao
2

  1. Korea Atomic Energy Research Institute, Daejeon, 34057, Republic of Korea
  2. University of Washington, Seattle, WA 98195, USA
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Abstract

In this study, the bio state of the alloy produced in the modified metal injection system was monitored after sintering. A new system operating with high gas pressure, far from the traditional injection model, has been established for material production. In this system, 316L stainless steel powders were molded using a PEG/PMMA/SA polymer recipe. During molding, approximately 60% 316L and 40% binder by volume were used. The samples obtained were sintered at different temperatures (1100-1300°C) after de-binding. Density measurement (Archimedes) and hardness tests (HV1) of the samples were measured as 6.74 g/cm3 and ~285 HV1, respectively. A potentiodynamic corrosion test was applied to monitor the effect of the amount of oxide in the structure of the 316L stainless steel produced. Corrosion tests were carried out in artificial body solutions. The corrosion rate was measured at the level of 17.08×10–3 mm/y. In terms of biocompatibility, a cytotoxicity test was applied to the samples and the life course of the bacteria was monitored. For the 316L alloys produced, the % vitality reached approximately 103%.
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Authors and Affiliations

Bünyamin Çiçek
1
Yavuz Sun
2
ORCID: ORCID

  1. Hitit University, Vocational School of Technical Sciences, Machine and Metal Technologies Department, Corum, Turkey
  2. Karabuk University, Engineering Faculty, Turkey
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Abstract

In this study, a research was conducted to recover metallic zinc and pig iron and to improve the purity and the recovery rate through a reduction process for zinc and iron in the byproducts that are generated after steelmaking dust treatment. As the result of the calcination, it was confirmed that Cl (6.06%) and K (3.37%) decreased to Cl (2.75%) and K (0.22%), respectively. For the zinc powder that was recovered with reaction temperature of 1100°C, reaction time of 4 hours, and argon gas of 1L/min as the optimal conditions. The measurement for the purity of zinc was 99.8% and the recovery rate was 92.14%. The melt reduction for recovering pig iron from the residue was reacted under reaction temperature of 1600°C, flux composition (CaO:SiO2) of 1:1, and reducing agent infusion ratio (residue: C) of 14:1, and the pig iron was measured to have a purity of 87.7% and a recovery rate of 91.81%.
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Authors and Affiliations

Jei-Pl Wang
1
ORCID: ORCID

  1. Pukyong National University, Department of Metallurgical Engineering, Department of Marine Convergence Design Engineering (Advanced Materials Engineering), Busan 48513, Korea
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Abstract

Azo dye is widely used in the textile industry since it is cost effective and simple to use. However, it becomes a continuous source of environmental pollution due to its carcinogenicity and toxicity. Various methods had been used to remove the azo dye in solution. One of the famous and frequently used i