航空弓形结构框喷丸强化变形计算及工艺规范建立

Calculation of Shot Peening Strengthening Deformation of Aerospace Arc-shaped Frame and Establishment of Process Specification

目的研究航空弓形结构框喷丸强化变形的力学理论、有限元模拟的预测方法,建立喷丸强化工艺规范,为国内航空工业中的喷丸工艺提供一定指导。方法首先利用有限元软件ABAQUS进行若干组不同喷丸速度的随机弹丸撞击模拟,创建与喷丸平均速度相关的喷丸诱导应力数据库,在此基础上,进行弓形结构框喷丸强化变形的理论预测和有限元仿真。在ABAQUS环境下开发一个快速模拟不同喷丸参数下弓形结构框喷丸强化变形的插件,实现各种不同类型的弓形结构框的自动前处理以及理论解和仿真解的给出。在以上研究的基础上,发展一套快速确定各类弓形结构框喷丸强化参数的工艺规范。结果针对某型号弓形结构框,在相同的喷丸参数下,理论计算的最大变形量为1.25 mm,有限元计算的最大变形量为1.13 mm,实验结果为1.8 mm。结合计算预测和工艺规范,确定了喷丸矫形区域及参数,最终弓形结构框的变形为0.15 mm,满足精度要求,验证了计算预测与规范的有效性。结论分析认为,建立的理论预测方法和有限元方法可以快速准确地预测弓形结构框喷丸强化变形结果。本研究对于国内航空工业中弓形结构框喷丸强化变形的快速仿真以及理论预测具有较大的工程价值。

This work aims to study the mechanical theory and finite element method(FEM)prediction method for shot peening deformation of aerospace arc-shaped frame,and establish the specification of shot peening process to provide guidance for shot peening in the domestic aviation industry.Firstly,several groups of random shot impact simulations with different shot speeds were carried out by ABAQUS,and a shot peening induced stress database related to the average shot speed was created.Based on this,theoretical prediction and finite element simulation of shot peening deformation of arc-shaped frame were carried out;in the ABAQUS environment,a plug-in for quickly simulating the shot peening deformation of arc-shaped frame under different peening parameters was developed.By using this plug-in,all operations could be done automatically in the fore treatments of ABAQUS for various types of arc-shaped frames,and theoretical and simulation results could be given at the same time.Based on the above research,a process specification for quickly determining the shot peening parameters of various arc-shaped frames was developed.For specific aerospace arc-shaped frame,the theoretical maximum deformation was 1.25 mm;the maximum deformation calculated by FEM was 1.13 mm;and the experimental result was 1.8 mm under the same shot parameters.Combined with calculation prediction and process specification,the shot peening area and parameters were determined;and the final deformation of the arc-shaped frame was 0.15 mm,which met the accuracy requirements.The validity of the calculation prediction and specification was verified.Through the analysis,theoretical prediction method and FEM can quickly and accurately predict the results of shot peening deformation of arc-shaped frame.This study is of engineering value for the quick simulation and theoretical prediction of the shot peening deformation results of the arc-shaped frame in the domestic aviation industry.