Two-step sintering effects on the microstructure and mechanical properties of forsterite scaffolds

In this study, we evaluate the effects of two-step sintering on the microstructure, compressive strength and porosity of forsterite scaffolds for tissue engineering application. Forsterite slurry was prepared and pre-cut foams were immersed in the slurry for 1 h. The saturated foams were then annealed at various times and temperatures using the two-step sintering method. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. The results showed that two-step sintering method can prevent the grain growth which occurs during the sintering process of scaffolds at high temperatures and subsequently provides higher compressive strength compared to conventional sintering method. The first step of the sintering process, which occurs at a higher temperature, is to provide initial binding through sintering and localized melting between the contact surfaces of adjacent grains and the second step at a lower temperature is to strengthen and complete the sintering process.