Finite Element Analysis Of Ceramic Femoral Head Stress Distribution And Preparation Technology Research

Joint pathological changes and damage which due to illness, sports injury, agingand other factors badly affect people′s quality of life. It needs artificial joint replacementto restore function. The first part of the paper carried out finite element analysis ofceramic femoral head, applied3D nonlinear finite element analysis method to simulatestress distribution of the zirconia ceramic femoral head-titanium alloy sterm, throughchanged in femoral head prosthesis model of various design parameters, analyzed themaximum von mises stress and its distribution characteristics. According to the stressdistribution nephogram of the femoral head, it has the same situation with the clinicalpractice. Research was shown that with the increase of applied load, the maximum vonmises stress of femoral head increases; with the increase of taper angle, the maximumvon mises stress of femoral head appears first decreased and then increased, with theincrease neck-shaft angle, the maximum von mises stress of femoral head decreased;with the increase of the femoral head diameter, the maximum von mises stressdecreased. According to the analysis results of finite element model, it providedvaluable experimental basis for the femoral head structure design, organizationoptimization and material selection, at the same time, also for the clinical application ofceramic femoral head put forward useful reference.With the development of the advanced materials manufacturing process, theceramic injection molding technology as a new type of near net shaping technology, hasbeen received material expert’s universal attention and gradually applied in theprecision ceramic production industry. Ceramic injection molding technology includingfeed preparation, injection molding, debinding and sintering, however, debinding andsintering stage is the most difficult control and time consuming longest key link in theimplementation process.The second part of the paper based on the ZrO₂ceramic power injection moldingtechnology, discussed the technique on zirconia ceramic head during the production of the key link, focuses on the study of low temperature thermal debinding and discussedthe mechanism of debinding. Depended on the thermal analysis of wax-based ZrO₂ceramic power injection feedstock, focused on the study of debinding process ofceramic injection molding and discussed the mechanism of debinding. By analyzing andevaluating the weight loss of the product, particle size shrinkage, defects on the surfaceand microstructure of morphology before and after the thermal debinding, the maindefects and causes of the large size ZrO₂ceramic injection molding has been discussedparticularly. Research shows that wax flow, bubble, cracking and other thermaldebinding defects mainly occured in the low temperature debinding stage. Then,combined with the “weight loss rate control” and “fixed-point isothermal control”thermal debinding way, the fundamental principles of the optimum wax-based ZrO₂ceramic power injection molding thermal debinding process was put forward. Finally,the traditional thermal debinding process was improved and optimized. Withoutextending the total debinding time, significantly improved the debinding qualified rateof the wax-based ZrO₂ceramic power injection molding, and got the densification ofthe ZrO₂ceramic head by the optimizing sintering process.