Optimizing Composition and Rigidity of Unidirectional Laminates for Total Hip Prosthesis Applications

Unidirectional composite structures are increasingly utilized in structural design due to their excellent compressive strength. The present study provides an evaluation of the fatigue performance of materials commonly used in hip prostheses such as Ti-6Al-4V, Co-Cr alloys, UHMWPE, and a silicon matrix composite reinforced with unidirectional carbon fibers in three different fiber volume fractions. Using Bergmann's loading factors, stress calculations were conducted for an 80 kg individual. The Goodman criterion and S-N curves were applied to assess fatigue life. Results show the unidirectional composite with 70% fiber volume fraction has the highest fatigue resistance, making it most suitable for high-stress applications. In contrast, Ti-6Al-4V and Co-Cr alloys showed moderate performance, while UHMWPE was found to be suitable for low-stress applications. These results underscore the necessity of selecting the ideal composition to maximize durability and fatigue resistance in essential mechanical applications. This finding suggests a promising alternative for improving the design and performance of femoral neck implants. This suggests a promising alternative for improving the design and performance of femoral neck implants.