Improvement the Mechanical properties of Al-Pb Alloy Prepared by Mechanical Alloying

Abstract

Al-Pb alloys are used as bearing due to their desirable bearing properties. Improving the mechanical properties of this alloy is the main objective of this research. In present work three types of powders of Aluminum(as base metal) with 10% lead and 4.5% copper by weight mixing by mechanical alloying process using ball milling for the period two hours. Homogenous distribution of powder was achieved. Five different compacting pressures, three different sintering temperatures and various duration times through sintering step had been selected; Vickers micro hardness, compressive strength and microstructure (optic microscope, SEM and EDX) were tested to achieve an optimum condition to manufacture this alloy. Two methods were selected to enhance the obtained optimum mechanical properties; First, artificial aging process showed increasing in mechanical properties(22% for hardness and 24% for compressive strength), second, the addition of SiC powder in different percentage weight(5,10,and 15%) which increased the hardness with increasing the additive percentage reached to 44% with maximum addition , in the other hand compressive strength decreased with increasing percentage of the addition .