Effect of TiH₂ addition on the grinding performance of Cu₃Sn intermetallic compound diamond wheels

In order to improve the sharpness and shape retention of Cu₃Sn intermetallic compound diamond grinding wheels, Cu₃Sn ball-milling powders, diamond grinding blocks and grinding wheels with different TiH₂ additions were prepared. The effects of TiH₂ addition on the grinding performance of Cu₃Sn intermetallic diamond grinding wheels were investigated by testing and analyzing the micro-morphology, oxygen content, physical phase composition, thermal effect, mechanical properties. The results show that the addition of TiH₂ has the effect of inhibiting the oxygenation of Cu₃Sn ball-milling powder, which is beneficial for the sintering of the powder. When the amount of TiH₂ added is 2.0wt%, the oxygen content decreases from 0.67% to the minimum value of 0.51%. The addition of TiH₂ improves the holding force of the matrix on the diamond, which can improve the flexural strength and hardness; when the amount of TiH₂ added is too much, the flexural strength and hardness will decrease instead. When the amount of TiH₂ is 1.5wt%, the flexural strength reaches the maximum value of 80.74 MPa, and the Rockwell hardness reaches the maximum value of 109.88 HRB when the amount of TiH₂ is 2.0wt%. The addition of TiH₂ can improve the grinding performance of the wheel, and also improve the sharpness and shape retention. When grinding cemented carbide YG8, the fastest feed rate of the grinding wheel increases from 0.02 mm/feed to 0.035 mm/feed. And the grinding ratio reaches a maximum value of 172.03 with addition of 2.0wt% TiH₂, compared with 51.09 of blank sample.