Optimization of Powder Metallurgical Parameters for Improving Corrosion Rate of Biodegradable Zinc-Hydroxyapatite Composite

The study investigates the impact of powder metallurgical factors on the corrosion rate (CR) of biodegradable zinc (Zn)-hydroxyapatite (HAP) materials. Factors such as HAP weight percentage (wt%), compaction pressure (CP), heating rate (HR), sintering temperature (ST), and dwell time (DT) were examined. Static immersion test was performed to determine the CR of the samples. The results showed an increase in CR with increased HAP wt%, while factors like CP, HR, and ST led to lower CR. The CR decreased with an increase in DT upto 18 min and thereafter increased. HAP wt% was found to be the most significant factor, contributing 57.95% on CR. A genetic algorithm-based optimization was conducted to minimize CR of Zn-HAP materials. The experimental CR value obtained at optimized levels, i.e., 3 wt% HAP, 34 MPa CP, 25 °C/min HR, 480 °C ST, and 30 min DT, were found to be 0.121 mm/yr, which was within the range of the predicted value 0.08 ± 0.044 mm/yr. This work presents a statistical modeling approach for predicting the CR of Zn-HAP composite for biomedical applications.