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Purpose: This paper aims to investigate the effect of laser surface texturing (LST) on the wear behavior of C-263 nickel-based superalloy and to identify the optimum wear operating condition. Design/methodology/approach: C-263 nickel-based superalloy was selected as substrate material and pico-second Nd-YAG laser was used to fabricate the waviness groove texture on their surface. Wear experiments were designed based on Box-Bhenken design with three factors of sliding velocity, sliding distance and applied load. Wear experiments were performed using pin on disc tribometer. Morphologies of textures and worn-out surfaces were evaluated by scanning electron microscopy and energy dispersive spectroscopy. Surface topographies and surface roughness of the textures were evaluated by weight light interferometry. The response surface methodology was adopted to identify the optimum wear operating condition and ANOVA to identify the significant factors. Findings: LST improves the wear resistance of C-263 nickel-based superalloy by appeoximately 82 per cent. Higher wear rate occurs at maximum values of all operating conditions, and applied load affects the coefficient of friction. Applied load significantly affects the wear rate of un-textured specimen. The interaction of sliding velocity and applied load also affects the wear rate of textured specimens. The optimum parameters to get minimum wear rate for un-textured specimens are 1.5 m/s sliding velocity, 725 m sliding distance and 31 N of applied load. For textured specimens, the optimum values are 1.5 m/s sliding distance, 500 m sliding distance and 40 N of the applied load. Originality/value: Literature on laser texturing on nickel-based superalloy is very scarce. Specifically, the effect of laser texturing on wear behavior of the nickel-based superalloy C-263 alloy is not yet reported. [ABSTRACT FROM AUTHOR]

A new-generation unalloyed low-carbon steel (containing 0.1 wt.% C) has been recently developed by the research group of the present corresponding author through incomplete austenitisation-based cyclic ice-brine quenching possessing an exceptionally high strength (UTS = 1.7 GPa) along with elimination of a yield point phenomenon. This is attributed to the evolution of a novel microstructure that consists of fine plate martensite crystals with a dispersion of nano-sized cementite particles and clusters. The present research work is conceived as the Part II of this investigation to establish this new-generation ultrahigh strength low-carbon steel as a unique wear-resistant steel substituting the conventional dual-phase steel along with the readily awaited in-depth correlation between wear mechanism and structural evolution. The wear behaviour of heat-treated steels is investigated against an alumina disc using a pin-on-disc tribometer. The steel subjected to incomplete austenitisation-based cyclic ice-brine quenching exhibits much better wear resistance than conventional dual-phase steel. Dominant microcutting and microploughing abrasion aggravate wear loss, especially at higher load, in dual-phase steel that inherently possesses lower matrix hardness. But, very high-surface hardness is attained in the incomplete austenitisation-based cyclic ice-brine quenched steel by virtue of a significant strain hardening of martensite matrix in between hard nano-sized cementite particles. Besides, the wear rate is not allowed to shoot up even at the highest load through the generation of hard abrasion-resistant tribo-oxide layer of Al2FeO4. This envisages an advent of novel wear-resistant steel as a better substitution for the dual-phase steel. [ABSTRACT FROM AUTHOR]

In the present study pure magnesium was taken as a base metal which is reinforced with various weight percentages of TiO2 (2.5, 5, 7.5, 10 % wt). This is done through a vacuum stir casting route with argon as a shielding gas to prevent oxidation. The prepared samples were machined using the Electric Discharge Machining (EDM) to achieve accurate dimensions for the study of tribological properties. A computerized pin-on-disc machine is used to study the dry sliding wear behaviour of the Mg-based composites. Wear losses were calculated using a variety of load parameters (10N, 15N, 20N, and 25N), sliding velocities (1 m/s, 1.5 m/s, and 2.0 m/s) and the weight percentage of the reinforcement. The results proved that the wear loss increased with an increase in the load, and decreased with an increase in the sliding velocity. The wear resistance is improved with an increase in the percentage of reinforcements in the matrix. The morphology and distribution of reinforcements were analysed by means of Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray (EDX) spectroscopy, respectively. The results revealed a uniform distribution of TiO2 particles throughout the magnesium matrix in the Mg-TiO2 composites. [ABSTRACT FROM AUTHOR]