螺杆的预应力硬态切削加工

Prestressed Hard Cutting of Screw

基于预应力切削原理,设计了一种用于车削加工的预应力加载装置,以解决对工件施加较大预应力同时进行车削的难题;采用PCBN刀具对加载不同预应力的螺杆进行了车削实验,研究了不同预应力条件下工件的预应力、工件表面的残余应力、工件表面粗糙度、预应力对切削力的影响以及PCBN刀具的磨损情况,并与普通硬态切削加工进行比较.实验结果表明:所设计的预应力轴向加载装置可有效地加载预应力;通过预应力硬态切削,可以在螺杆加工表面产生较大的残余压应力;预应力硬态切削加工的工件表面质量良好;预应力对切削力和刀具磨损没有明显的影响.

In order to solve the problem existing in the turning of workpiece simultaneously being loaded with high prestress,a prestress-loading device was designed for the prestressed turning.Then,some turning experiments for a screw were carried out with PCBN tools under different prestresses to investigate the loaded prestress,the surface residual stress,the surface roughness,the impact of prestress to cutting force and the wear of PCBN tools.More-over,the results were compared with those of the original hard cutting.It is found that the designed loading device can effectively load prestress on workpiece,that the prestressed hard cutting generates high residual compressive stress on the screw surface and results in fine machining surface,and that the prestress has no significant effect on the cutting force and tool wear.