Sintering Process of Cu–28Zn Brass Alloy: Statistical Investigation

Abstract

In this study, the effect of process parameters on the super-solidus liquid-phase sintering of Cu–28Zn brass alloy was evaluated by using response surface methodology. Compaction pressure of green samples, sintering temperature, and sintering time were considered as the input variables, while sintering density, densification parameter, porosity percentage, volumetric shrinkage percentage, and impact energy were considered as process responses. Microstructural, fractography, and hardness tests were investigated. Results indicated that the sintering densities of low-pressure compacted samples and high-pressure compacted samples were 7.44 and 7.17 $${\raise0.7ex\hbox{${\text{g}}$} \!\mathord{\left/ {\vphantom {{\text{g}} {{\text{cm}}^{3} }}}\right.\kern-0pt} \!\lower0.7ex\hbox{${{\text{cm}}^{3} }$}}$$, and the porosity percentages of those samples were 10.25% and 13.03%, respectively. Observations revealed that increase in sintering temperature and sintering time led to the generation of the super-solidus liquid phase with filled pores. Microstructural observations and fractography revealed the effect of liquid-phase distribution to the physical and mechanical properties. Finally, it was found that the sintering temperature had the most significant effect on the sintering density, densification parameter, porosity percentage, volumetric shrinkage percentage, and impact energy. The compaction pressure and sintering time had lower effect on all responses.