Experimental Research And Processing Deformation Simulation On The Thin-Walled Structure Components Of Titanium Alloy

The machining distortion is one of the neck problems during the aero integrated-structure parts. Now titanium alloys are used widely in aerospace monolithic components owing to theirs excellent mechanical properties. Unfortunately, the machining distortion of titanium alloy monolithic component is more complex and troublesome because of its large machining loads during cutting process, small elastic modulus and complex distribution of the initial stress. This state of affairs reduces the productivity and lowers the precision of the finished products. Therefore, the study work of titanium alloy monolithic component machining distortion has the significant practical significance.In view of the complex nature of distortion problem, Take titanium alloy monolithic component TC4 as object of study, a method combining finite element simulation with experiment and theoretical analysis is adopted. Then, the distortion law of monolithic component is researched deeply and widely.Firstly, the paper introduces the definition and classification of the residual stress and its causes and effects, tells the residual stress test method and the basis of finite element method's theoretical analysis. The specific steps of initial residual stress's simulation are proposed by analyzing deformation mechanism of monolithic component. While it provides detailed course and theoretical basis for initial residual stress's simulation process and machining deformation.Secondly, base on the thermo-mechanical and elastic-plastic theories, an anneal analysis of titanium alloy is carried out by applying a sequentially coupled procedure, and the residual stress distribution of blank is gained. The anneal blank of the aerospace monolithic components with initial residual stress are obtained. Using the technology of element birth and death, the result of residual stress's simulation is realized. Compared with the experimental results, Outline distortion law of the whole of thin-walled structure is drawed.Finally, though the milling experiments of no initial residual stress's work-pieces and initial residual stress's work-pieces. The machining distortion law of monolithic component caused by release of initial residual stress, cutting load and multi-factors coupling are researched respectively. That indicates the cutting load is the main element of causing machining distortion.