玻璃模压成形用微沟槽磷化镍模具的超精密切削加工

Ultraprecision microgroove machining of nickel phosphorous plating mold for glass molding

最佳邻接量是高精度加工玻璃模压成形用磷化镍镀层材料微沟槽模具的重要参数。本文提出了一种利用小角度微沟槽交叉切削技术快速确定微沟槽最佳邻接量极限范围的方法。该方法利用沟槽小角度交叉切削材料去除形式与沟槽邻接切削相近的特点,对微沟槽邻接量的极限范围进行预测。首先,以沟槽交叉角度和交叉沟槽深度为变量设定切削条件,得到多组渐变棱;然后,观测交叉渐变棱形貌并结合材料塑性变形法则与脆塑转变理论分析棱边上的材料去除状态;通过观察交叉渐变棱与沟槽邻接脊部在切削过程中去除材料的截面形貌建立二者的关系;最后,分析交叉渐变切入棱与切出棱形貌的差异,确定脆塑转变的邻接量范围。基于上述方法,观测了交叉渐变棱的形貌并进行几何计算,确定磷化镍模具微沟槽邻接切削产生脆性剥离现象的临界邻接量范围为570~720nm。利用微沟槽模具超精密切削加工实验验证了该方法的有效性,加工出了高质量模具并用于微沟槽玻璃模压成形,实现了玻璃微沟槽的精密制造。

The optimal adjacent amount range is an importance parameter in ultra precision microgroove machining of nickel phosphorous（Ni-P）plating mold for glass molding.This paper proposes a method by using small cross angle microgroove cutting to test the optimal adjacent amount range in the process of single point diamond cutting of microgrooves rapidly.In this method,the limits of the adjacent amount range is forecasted based on the similarity of the material removal form between the small cross angle microgroove cutting and the adjacent microgroove cutting.Firstly,the cross angle and microgroove depth are set as the microgroove cutting variables to perform experiments and to obtain several pairs of arrises.Then,the material removed state is analyzed based on the plastic deformation law and brittle-ductile transition theory through the observation of the gradient arrises.Thesection of removed material in gradient arris machining process is analyzed and compared with that of adjacent microgrooves,and their relationship is established.Finally,the differences between the exit arrises and the entrance arrises are analyzed and the adjacent amount range of the brittle-ductile transition area is determined.According to this method,the arris morphology is observed and calculated,it is found that the critical adjacent amount range of the brittle dissection phenomenal is 570-720 nm in ultra precision microgroove machining of nickel phosphorous（Ni-P）plating mold.The feasibility of the method is verified by ultraprecision machining of the brilliant microgroove mold.The mold is put into service in glass molding process and high precision optical glass microgrooves are manufactured.