The Numerical Simulation Of TC4 Titanium Alloy Shot Peening

Shot peening is a kind of surface strengthening technology which can effectively improve the surface integrity and the fatigue life of the parts.It is widely used in aviation,aerospace,automotive and other civil and military fields.However,due to the complexity of the mechanism of shot peening and numerous parameters,it remains to be further studied.In this paper,TC4 titanium alloy was selected as the research object.Based on the finite element method,the mechanism of TC4 titanium alloy shot peening was studied.The Johnson-Cook material model,which reflects strain hardening and strain rate hardening of materials at high velocity impact,is used to define the properties of the target.The effects of shot peening parameters and surface quality of the target were studied systematically by using ABAQUS finite element software.The main works of this dissertation are outlined as follows:In Chapter 1,the properties and applications of titanium and titanium alloys are introduced briefly.At the same time,the mechanisms and research status of shot peening are summarized.The importance of numerical simulation of shot peening is also pointed out.In Chapter 2,the basic theory of static implicit and dynamic explicit finite element method was expounded.The influence of the number of repeated impacts and the shot material on the shot peening was studied by establishing a single shot finite element model of shot peening.In Chapter 3,the multi-shot random shot peening finite element model was established through the second development interface of ABAQUS,using Python language.Then,the effect of shot peening time,shot peening speed,shot peening angle and shot diameter on residual stress and surface roughness of the target was studied by the model.In Chapter 4,for the case of non-ideal smooth surface of the target,the surface roughness of the target was simulated by the fitting function.Then,the effect of the initial roughness of the target on the shot peening was studied by the finite element model with initial surface roughness.In Chapter 5,the work is summarized and some future works is proposed.