Cryogenic Treatment And In The Process Of Tapping Tap Stress Field Numerical Simulation

As a continuation of the heat treatment process during the cooling process,the deep cryogenic treatment has been paid more and more attention, and it canimprove the mechanical properties of the workpiece effectively. However, in therespect to improve the mechanical properties, it is more important to eliminateor mitigate the residual stress in the workpiece. The research ues the deepcryogenic treatment to adjust the surface residual stress of W6Mo5Cr4V2high-speed steel tap. Deep cryogenic treatment process is adhering to theadvantages of the heat treatment process, which object placed in a specific lowtemperature and make the material microstructure and stress state changeprocess, and it can improve the strength, wear resistance and toughness of thematerial to a considerable extent. It is non-polluting， easy to operate,undestroyed for the workpiece, and has considerable economic and marketprospects.The deep cryogenic treatment can eliminate the surface residual stress inthe workpiece effectively, which has been verified in the experiment. Theexperiment results show that deep cryogenic treatment can be used as a newmethod for the control and adjust of machined surface residual stress. In order tofully understanding the residual stress of cryogenic treatment, this project usethe finite element method. The main research work includes the following:1、Building three-dimensional finite element model of tap in the finiteelement software of ABAQUS, and use it to simulating quench, temper and deepcryogenic treatment heat treatment module. This research predicts and calculatesthe surface residual stress of1/3Tap model, and obtains the distribution ofsurface residual stress of different heat treatment.2、It simulates the process of high-speed steel tapping TC4titanium alloyusing finite element software of ABAQUS. After tapping, it research the surfaceresidual stress of tap from two aspect: the axial residual stress and radial residualstress.3、Base on the residual stress of tap, this research analyze the impact of the process, which is different composition of quenching, tempering and cryogenictreatment process and compares the result of residual stress of deep cryogenictreatment and normal treatment in the simulation of tapping titanium alloy.This topic research is supported by Natural Science Foundation of China,the project number is:51275333.