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

• B2O3 doped LZAS vitrified bonds were investigated for diamond grinding tools application.
• The activation energy for the crystallization and Avrami parameter has been calculated.
• The crystallinity and morphology of crystals were affected by the B2O3 additives.
• Positive correlation of crystal content, micro-images and properties.
• The vitrified bond B8 is suitable for diamond grinding tool application.

The effects of B2O3 on the crystallization and properties of Li2O–ZnO–Al2O3–SiO2 (LZAS) vitrified bonds were investigated for diamond grinding tool application. The results show that the [BO3] in the glass structure increased with increasing B2O3 content. The glass transition temperature and the first crystallization peak temperature decreased, while the second crystallization peak temperature increased with increasing B2O3 content. The increase in B2O3 content has a little influence on the value of Avrami exponent (n), keeping two-dimensional crystal growth mechanism. Realized composite with 8 mol% B2O3 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/cm2 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.