Crystallization and properties of B2O3 doped LZAS vitrified bond for diamond grinding tools

Abstract The effects of B 2 O 3 on the crystallization and properties of Li 2 O–ZnO–Al 2 O 3 –SiO 2 (LZAS) vitrified bonds were investigated for diamond grinding tool application. The results show that the [BO 3 ] in the glass structure increased with increasing B 2 O 3 content. The glass transition temperature and the first crystallization peak temperature decreased, while the second crystallization peak temperature increased with increasing B 2 O 3 content. The increase in B 2 O 3 content has a little influence on the value of Avrami exponent ( n ), keeping two-dimensional crystal growth mechanism. Realized composite with 8 mol% B 2 O 3 of LZAS vitrified bond has a higher crystal volume fraction and a uniform sphere-shaped microstructure. Moreover, vitrified bond B8 exhibits a high bending strength (198 MPa), a good chemical durability (20 days, DR = 3.1 × 10 − 9 g/cm 2 min), an appropriate TEC (4.63 × 10 − 6 /°C) and a good wettability to diamond abrasives, suggesting that it would be a promising material for diamond grinding tool.