The Effect of Tin and Heat Treatment in Brass on Microstructure and Mechanical Properties for Solving the Cracking of Nut and Bolt

Abstract

This work studied the effect of tin (1%Sn) addition in brass 60%Cu+40%Zn (commercial grade) by casting process conducted poured melt metals inside a sand mould and heat treatment in cast brass on microstructure and mechanical properties for solving the cracking of nut and bolt. Three conditions of brass sample for experiment viz.- brass 60%Cu + 40%Zn (commercial grade), brass 60%Cu + 39%Zn+1%Sn (as-cast) and brass 60%Cu+39% Zn+1%Sn (precipitation hardening). The microstructure of specimens all condition, it was found that consists of α phase and β phase. Which brass addition 1% Sn, the β phase content in α phase matrix structure more than brass commercial grade. For microstructure of brass produce by precipitation hardening, shape of α phase are slender and long which have slight distributed in β-phase. The mechanicals properties, that is hardness, ultimate tensile strength and compressive strength. It was found that the brass 60%Cu+39% Zn+1%Sn (precipitation hardening), all test mechanical properties it was higher than the all samples condition. This results can be explain incharacterization of microstructure to gives deformation of copper alloy.