Tribological Properties of AA7175 Reinforced with SiC, B₄C and Gr Hybrid Composite Using Taguchi Design Technique

The wear test was carried out by the computerized pin-on-disk tribometer with the counter surface of an EN32 steel disk (60–62 HRC). The square pin composite samples were used for wear testing. The orthogonal array L9 was selected by the Taguchi design technique. The three parameters applied loads (10N, 20N, and 30N), sliding speeds (1.5 m/s, 2 m/s, and 2.5 m/s), and reinforcement contents (3, 6, and 9) % of weight affected the wear rate and coefficient of friction during the test. ANOVA analysis shows significant results related to the input parameters.

The results show the wear rate of hybrid composites was observed better than aluminum. SEM test was used to characterize the microstructure of the worn surface. It was investigated from the experiment that the wear rate and the coefficients of friction decrease with increment of sliding velocity and wt% of SiC, B₄C, and graphite. The presence of SiC, B₄C, and graphite reinforcement particles and other phases was observed by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM) test. It has been observed that 9%wt. composites were found better wear rates compared to the other composites.