超高速陶瓷CBN砂轮结构优化设计

Optimization Design of Vitrified CBN Wheel Structure in Super High-speed Grinding

以抑制砂轮径向膨胀量、减小砂轮最大和最小平均应力为优化目标,通过建立超高速砂轮基体内部微小单元应力应变与其增量之间的关系,得出了变厚度砂轮基体强度校核的理论公式。采用有限元方法对砂轮基体材料和截形进行了优化设计分析,对超高速情况下砂轮的气动功率及超高速砂轮气流场温度进行了分析,同时考虑节片式砂轮特点,对砂轮节块数量和节块厚度进行了优化分析,研究表明,钛合金双曲线截形基体砂轮在贴片数量及大小一定时对于抑制砂轮膨胀量和平均等效应力有着明显的优势。

An optimization objective was set up to control the radial displacement and to reduce the equivalent stress of the super high-speed grinding wheel.By established models for the connection between inner micro-unit＇s displacement and stress of wheel base,strength check of the theoretical formula about variable cross-section wheel was also established.A finite element analysis method was used to optimize wheel base type and material.The wheel pneumatic power and flow field temperature under ultra-high speed situation were also analyzed.Taking into account the characteristics of segment wheel,wheel segments number and thickness were optimized.The study has shown that the hyperbolic-type titanium alloy base wheel has a clear advantages to restrain the radial expansion and the average equivalent stress of wheel while its segments number and size have proper certain optimization value.