Powder metallurgical production of SS316L metallic implant with a hybrid bioactive composed of HA and YSZ: Effect of compaction pressure on morphological, mechanical characteristics and bioactivity properties

Abstract

A novel hybrid bioactive ceramic for metallic implant was developed to achieve strong interfacial bonding and osseointegration. This study investigated the morphological, mechanical characteristics, and bioactivity properties of SS316L/HA/YSZ composite through the powder metallurgy method. Various compaction pressures (200, 300, and 400 MPa) were explored to address the difference in Young's modulus between the implant and human bone. Subsequently, the composites were sintered at 800 °C for 2 h with a heating rate of 10 °C/min. Microstructural and mechanical evaluations were performed using SEM, density, and compressive strength tests, while the bioactivity of the composites was assessed through an immersion test. The findings revealed that lower compaction pressure leads to lower densification, higher porosity, higher compressive strength, lower Young's modulus, and increased apatite deposition. The ideal compaction pressure of 200 MPa was identified, as it aligns with the mechanical and bioactivity qualities required for cortical bone, resulting in a compressive strength of 121.07 MPa, Young's modulus of 31.39 GPa, porosity of 33.29% and denser apatite formation (1.64%).