EXPERIMENTAL INVESTIGATION OF TRIBOLOGICAL CHARACTERISTICS ON AA7068–ZrB2 IN-SITU AMCs

In the present era, aluminum-based metal matrix composites, commonly known as aluminum matrix composites (AMCs), play a crucial role in fabricating lighter weight components in the aerospace, automotive, aircraft and marine industries. Intensive research is required to fabricate AMCs economically. In this recent research, AA7068–ZrB2 AMCs were successfully produced using the in-situ method of fabrication. The inorganic salts such as K2ZrF6 and KBF4 reacted with molten aluminum at 850∘C and formed ZrB2 particles in the aluminum melt itself. The castings of AA7068–ZrB2 AMCs were obtained with 0, 3, 6 and 9 volume fractions (vol.%) of ZrB2 in-situ particles. The pin-on-disc wear apparatus was used to conduct the dry sliding wear analysis of AA7068–ZrB2 in-situ AMCs. The wear experiments were conducted in line with the Design of Experiments (DoE). An orthogonal array of L16 was employed for the DoE. The effects of wear parameters such as vol.% of ZrB2 particles, sliding speed, sliding distance and normal load on the wear rate (WR) and coefficient of friction (COF) were observed. The effects of individual parameters on the WR and COF were observed by contour plot, residual plot and Analysis of Variance (ANOVA). The worn surfaces of AA7068–ZrB2 (0, 3, 6 and 9 vol.%) AMCs were also observed using the field-emission scanning electron microscopy (FESEM).