Research On Machining Precision Of Aerospace Aluminum Alloy Y-shaped Deep Groove

With the development of spaceflight rocket in China,it is more and more important to process Y-shaped deep groove of thin-walled ring of aerospace aluminum alloy.Because of its large size and poor rigidity,it is difficult to guarantee machining precision because of the special requirement of machining tool and fixture.Without good machining precision,it is difficult to ensure the overall coordination of large space rocket,which restricts the development of space industry in China.Based on the main factors that affect the machining accuracy,the problem of improving the machining accuracy of the rear bottom transition ring of the key parts of space is studied in this paper.This paper analyzes the main factors that affect the machining precision in the process of production and machining,and gives the research scheme.According to the analysis of the main factors,the calculation of the cutting force of the circular blade,the research on the machining precision of the cutting tool and the optimization of the cutting parameters are carried out.Firstly,the cutting force is obtained by using ABAQUS software to simulate the machining process.Combined with the unit cutting force calculation method,the cutting force model of circular blade is established.The calculation results are verified by experiments,and it is proved that the model calculation results have certain guiding significance.Secondly,the machining error of the non-standard cutting tool used in the bottom transition ring machining is analyzed by finite element method.The results show that the original tool has certain instability,which will have a certain impact on the machining accuracy.Therefore,the experiment is designed: the machining accuracy of the non-standard tool is compared with the actual machining precision by welding the blade and the cutter body,the machining error of the non-standard tool is obtained,and the optimization scheme to improve the machining accuracy is given.Thirdly,according to the analysis of the problems existing in the machining workpiece and the rear bottom transition ring in the machining workshop of the rocket manufacturer,the factors affecting the machining accuracy are found out.In the range of design and given machining parameters,the cutting parameters are optimized by orthogonal test,and the combined values of cutting parameters are obtained when the machining precision is the highest,and the range of cutting speed,feed rate and feed rate are analyzed.The ratio of the degree of influence of each factor to machining accuracy is obtained.