The mechanism in which the coatings made by thermal spraying adhere to the substrate is in most cases of a mechanical nature, thus being dependent on the morphology of the substrate surface. This paper study how the texture of the substrate influences the behavior of dry sliding wear, a behavior based on the adhesion to the substrate of the analyzed coatings. For this purpose, a Co – base powder, was chosen for atmospheric plasma spraying. For the substrate, a rectangular profile made of low-alloy steel was chosen, the surface of which was textured by mechanical abrasion, in order to obtain different degrees of roughness: sample S1 – Ra1 = 1.59 µm, sample S2 – Ra2 = 2.32 µm, sample 3 – Ra3.1 = 1.25 μm, Ra3.2 = 3.88 μm. In the case of sample 3, the texturing was done on one direction, with an elongated profile, so that the effect of the main direction of dry sliding wear on the quality of the coating could be studied. The tests were performed on an Amsler test machine, at constant load, for 1 hour. The samples were mounted in a fixed position, and the wear occurred on the basis of the rotation of the metal disc, without lubrication. It was found that the coating of sample 1 was the most affected, resulting even a partial delamination, and the best behavior was recorded in the case of sample 3.1.

The present investigation has been made to assess the influence of B4C reinforced with Ti-6Al-4V matrix prepared by powder metallurgy route. High energy ball milling was used to prepare the composites. Cylindrical preforms were prepared using suitable die set assembly. The green preforms were sintered in the muffle furnace at 900°C for 1 h. Further the preforms were cooled inside the furnace till the room temperature has attained. SEM with EDS mapping analysis was used to evaluate the morphology and elemental confirmation of the prepared composite. The density and hardness of the samples are determined using Archimedes principle and Rockwell hardness testing machine. The wear resistance of the samples was determined by employing a pin on disc apparatus. The hardness of the composites (Ti-6Al-4V /10B4C) was increased while comparing to the base material (Ti-6Al-4V) which is attributed to the presence of hard ceramic phase. Response Surface Methodology (RSM) five level central composite design approach was accustomed and it minimised the amount of experimental conditions and developed mathematical models among the key process parameters namely wt. % of B4C, applied load and sliding distances to forecast the abrasive response of Specific Wear Rate (SWR) and Coefficient of Friction (CoF). Analysis of variance was used to check the validity of the developed model. The optimum parameters of specific wear rate and coefficient of friction were identified.

The versatile application of titanium alloy in the aerospace industry and it’s hard to machine characteristics focus towards the additive manufacturing. The Ti-6Al-4V alloy is manufactured using the electron beam source with a novel method of prepositioned titanium alloy wires. The tribology of the additive manufactured titanium alloy under dry sliding condition is experimented and analysed using Taguchi technique. The targeted objective of minimum tribological responses are attained with the identified optimal parameters as load – 9.81 N, sliding velocity – 3 m/s, sliding distance – 3000 m for minimum specific wear rate and load – 9.81 N, sliding velocity – 3 m/s, sliding distance – 1000 m for minimum coefficient of friction. Among the parameters tested, load is found to be the dominant factor on the tribology of additively manufactured titanium alloy. The morphological analysis on the worn surface and debris revealed the existence of abrasion, delamination and adhesion wear mechanisms. The increase in the load dominantly showed the appearance of delamination mechanism.