Field Activated and Pressure Assisted Bonding Mechanism of Ultra-Hard Materials of AlMgB₁₄ to Metal

Abstract

In this study, the AlMgB₁₄ enhanced by TiB₂ was synthesized and bonded to Nb simultaneously by field activated and pressure assisted synthesis (FAPAS). Microstructure investigation showed that TiB₂ particles distributed in the AlMgB₁₄ uniformly, with some impurities MgAl₂O₄ formed along the TiB₂ boundary. Cross section investigations indicated that transition region of about 180μm wideness between the Nb substrate and the synthesized AlMgB₁₄-TiB₂ was formed. Further investigation showed that the transition region could be divided into two parts: one part was formed through the element of B diffused into the Nb substrate; another part was mainly composed of some TiB₂ particles. Due to the small atomic diameter, the diffusion of the B into the substrate was noticeable which led to the successful bonding process. The microhardness increased gradually from the Nb substrate to the synthesized AlMgB₁₄-TiB₂ with the maximum value of 3780HV1.0.

Keywords:

• AlMgB₁₄-TiB₂
• Nb
• bonding mechanism
• interfacial microstructure
• ultra-hard materials

Acknowledgements

This project is supported by National Natural Science Foundation of China (51405328).