模具钢超高速磨削的温度场仿真

Simulation Study on Super-speed Grinding Temperature Field for Die Steel

模具钢一般具有较高的淬透性和耐磨性,很难通过磨削实现精密加工。由于利用传统的磨削加工方法会产生大量的磨削热,导致工件发生表面烧伤和裂纹,严重影响工件的加工精度和加工质量。随着目前超高速磨削技术的飞速发展,模具钢等难加工材料的精密磨削已成为可能。为了解决超高速磨削过程中磨削温度的合理控制问题,提出在DEFORM-3D软件上建立单颗磨粒CBN砂轮超高速磨削温度场模型。根据不同砂轮线速度下磨削弧区温度场进行了仿真与分析,发现当磨削速度超过某一数值时,磨削温度不会继续升高,甚至略有下降。证明超高速磨削技术可精密加工普通磨削难以加工的一些难加工材料,具有重要的现实意义。

Die steel is a kind of material which has the characteristics of hardenability and wear resistance. It is hard to machine by grinding precisely. In addition, it would generate large amount of grinding heat by using tradition- al grinding. That may lead to bums and cracks which have a great impact on machining accuracy and quality. During the development of super-speed grinding technology, it is possible to grind some hard materials like die steel accu- rately. At the beginning, the super-speed grinding temperature field model which has a single abrasive grain CBN wheel was established with software DEFORM-3D in order to know the change of grinding temperature and control it properly in the super-speed grinding process. And then, according to the finite simulation and analysis of grinding arc temperature field in different speeds, it was found that when grinding speed exceeds a certain value, the grinding temperature does not increase and sometimes even falls down a little. It is of great practical significance that some special materials grinded by traditional grinding difficuhly can be machined accurately by super-speed grinding.