A cobalt-chromium-based biomaterial mimics the flexibility of human bones and possesses excellent wear resistance. The new biomaterial could be used for implants such as hip or knee joint replacements and bone plates, alleviating problems associated with conventional implant materials.
Using a cyclical heat treatment technique, Xu and his colleagues successfully prepared large single crystals sized several centimeters. The developed Co-Cr-Al-Si (CCAS) alloy demonstrated a 17 percent strain recovery rate — twice that of commercial Ti-Ni shape memory alloys. Moreover, the CCAS's Young's modulus was extremely low, resembling the flexibility of human bones.
The research group focused on lessening the Young's modulus gap between metal implants and human bones. When a material is flexible, it has a low Young's modulus. When it is stiff, it has a high Young's modulus.