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 beta boundary and refinement of the prior beta grains. Cast Ti-B alloys with a good combination of greater tensile ductility and strength can be obtained with very low boron addition. (C) 2003 Elsevier Science B.V. All rights reserved.