Influence of boron addition on microstructure and mechanical properties of dental cast titanium alloys

As-cast titanium alloys prepared using a dental cast machine with a series of boron additions have been studied using an optical microscope, XRD, SEM, and hardness and tensile testing. It has been shown that a small amount of boron addition induces a significant refinement of as-cast structure and improvement of mechanical properties. Titanium borides, TiB particles, are observed in Ti matrix. Tensile ductility of cast Ti–B and Ti–0.5Si–B alloys is improved obviously when boron content is about 0.086–0.14 mass%. This is primarily due to the role of borides precipitated at the prior β boundary and refinement of the prior β grains. Cast Ti–B alloys with a good combination of greater tensile ductility and strength can be obtained with very low boron addition.