On the characterization of functionally graded biomaterial primed through a novel plaster mold casting process

Abstract

The current work presents a novel plaster mold casting (PMC) process for fabricating functionally graded biodegradable materials (FGBMs) for orthopedics applications. According to the proposed route, the plaster molds were first prepared by using a hybrid and variable mixture of Plaster of Paris (PoP) and hydroxyapatite (HAP). Upon drying, molten magnesium (Mg) alloy was poured in the mold cavity and allowed to solidify. Various experiments have been conducted as per Taguchi based design of experimentation to study the effect of PoP_X/HAP proportion, mixing time, and baking times on mechanical, corrosion, and cytocompatibility performances of the resulting FGBM. It has been revealed by the scanning electron microscopy (SEM) that uniform layers of HAP particles were developed on the prepared specimens, revealed the novelty of the route. The mechanical properties, in case of surface hardness and impact strength, the optimum results were obtained with PoP(x = 90% by wt.) and HAP(y = 10% by wt.). Further, the corrosion investigations highlighted that the sample prepared with PoP(x = 70% by wt.) and HAP(y = 30% by wt.) proportion possessed excellent corrosion resistance. Moreover, the cytocompatibility analysis revealed that all the developed FGBM are substantially bioactive and promoted cell adhesion, proliferation, differentiation, and various other cytoplasmic activities. However, in this case, FGBM with PoP(x = 70% by wt.) and HAP(y = 30% by wt.) proportion was found superior. The overall results of the present work supported the developed FGBM components and involved the PMC route as a potential candidate for various orthopedics fabrications.

Keywords: Biocompatibility; Functionally graded bio-composite; Hydroxyapatite; Magnesium; Mechanical strength; Plaster mold.