Surface Reaction Layer and Mechanical Performance of Low Rigidity Titanium Alloy, Ti-29Nb-13Ta-4.6Zr, Cast by Dental Precision Casting Method

摘要

Newly developed β type titanium alloy, Ti-29Nb-13Ta-4.6Zr, for biomedical applications, and conventional α + β type titanium alloy, Ti-6Al-4V ELI, for dental and biomedical applications were conducted with dental precision casting using commercial alumina and magnesia based investment materials, and modified magnesia based investment material, and then their mechanical properties and surface reaction layers were measured and examined. Elongation of Ti-29Nb-13Ta-4.6Zr cast using commercial alumina based investment material is lower than those of Ti-29Nb-13Ta-4.6Zr cast using modified magnesia and commercial magnesia based investment materials although strength is nearly the same among these cases. Volume fraction of casting defect (shrinkage) of Ti-29Nb-13ta-4.6Zr cast using modified magnesia based investment material is much greater than that of Ti-6Al-4V ELI cast using modified magnesia based investment material. Elongation of cast Ti-29Nb-13Ta-4.6Zr and Ti-6Al-4V ELI tends to decrease slightly with increasing the volume fraction of shrinkage.