DOE-based experimental investigation and optimization of hardness and corrosion rate for Cu-x%Al2O3 as processed by powder metallurgy

Copper alumina (Cu-x%Al2O3) was prepared from micro-sized powder particles through the powder metallurgy (PM) process. Experimental runs were designed according to the design of experiments (DOE) methodology to investigate the effect of alumina concentration and sintering time on the hardness and corrosion rate of the powdered composite. Four sintering times were tested (1, 2, 3, and 4 h) in combination with different levels of alumina concentration (1 wt%, 3 wt%, 6 wt%, and 10 wt%). Given the narrow range of the sintering temperature for copper alumina, this temperature was fixed at 900 ℃, whereas the compaction pressure was set at 300 MPa. Collected data were analysed based on the analysis of variance (ANOVA) approach and complemented with microscopic analysis. Optimization techniques were used to identify the optimal settings of sintering time and alumina concentration for the PM composite.