20th International Metallurgy and Materials Congress, İstanbul, Turkey, 10 - 12 June 2021, pp.445-448
Boron carbide which has a high hardness and friction strength is a well reinforcement material for aluminum composites to be able to improve its properties. In this study various amounts of B4C (0, 5, 10 and 15%) particles and 2% of stearic acid as PCA were added to Al powders with commercial purity. Then these mixtures were ball milled with 5 hrs using a planetary ball mill under vacuum conditions. The ball to powder weight ratio and rotational speed were 10:1 and 400 rpm, respectively. 3 g of ball milled powder mixture were pressed under 720 MPa with a metal mold having a diameter of 14 mm. Following this green samples were sintered at 600 °C under Ar atmosphere for 60 mins. The properties of the products were investigated by SEM, Brinell hardness, and apparent density measurements. Additionally the wear rates of the samples were obtained by using a Pin-on disc wear testing device. According to the results, the particles were homogeneously dispersed and low amounts of porosity were observed also the density measurements prove this result. Because B4C has a specific weight very close to pure aluminum (2,52 gr/cm3), no significant difference between the samples were encountered. Moreover increasing B4C amount increases the wear resistance of the composite samples. On the contrary it was found that hardness values decreases with the increasing amount of reinforcement ratio.