DRY SLIDING WEAR BEHAVIOR OF DIFFUSION BONDED AZ-91 MAGNESIUM ALLOY REINFORCED WITH SIC PARTICLES

Magnesium composites reinforced with 2, 4, 6 Wt.% of silicon carbide particles at different particle size of 10, 25 and 45 mm was synthesized using diffusion bonding process. Further the samples for scanning electron microscopic analysis and tribological analysis were made from the composites. Dry sliding wear test was carried out with L27 orthogonal design array on pin on disc tribometer. Mass loss of the pins was measured and wear rate was calculated. A statistical analysis was performed with the measured wear rate, the optimal parameter combination level was identified with main effect plot. From ANOVA analysis the significant parameters was identified

Hot deformation behavior and processing maps of diamond/Cu composites

The hot deformation behaviors of 50 vol pct uncoated and Cr-coated diamond/Cu composites were investigated using hot isothermal compression tests under the temperature and strain rate ranging from 1073 K to 1273 K (800 C to 1000 C) and from 0.001 to 5 s1, respectively. Dynamic recrystallization was determined to be the primary restoration mechanism during deformation. The Cr3C2 coating enhanced the interfacial bonding and resulted in a larger flow stress for the Cr-coated diamond/Cu composites. Moreover, the enhanced interfacial affinity led to a higher activation energy for the Cr-coated diamond/Cu composites (238 kJ/mol) than for their uncoated counterparts (205 kJ/mol). The strain-rate-dependent constitutive equations of the diamond/Cu composites were derived based on the Arrhenius model, and a high correlation (R = 0.99) was observed between the calculated flow stresses and experimental data. With the help of processing maps, hot extrusions were realized at 1123 K/0.01 s1 and 1153 K/0.01 s1 (850 C/0.01 s1 and 880 C/0.01 s1) for the uncoated and coated diamond/Cu composites, respectively. The combination of interface optimization and hot extrusion led to increases of the density and thermal conductivity, thereby providing a promising route for the fabrication of diamond/Cu composites