Research On Arc Forming And Milling Of Titanium Alloy Thin-walled Parts

Titanium alloy is used more and more widely in aerospace field,in order to obtain superior performance,more and more critical components are made of titanium alloy,many of these parts are thin-walled parts.The traditional manufacturing method of such titanium alloy thin-walled parts manufacturing efficiency is low,high cost,difficult,with the development of arc forming technology,the use of arc forming process for titanium alloy thinwalled parts manufacturing is a viable technical approach,this technology can greatly reduce the material removal rate,improve production efficiency.This paper mainly studies the arc forming process of TC4 titanium alloy thin-walled parts,and get the following results:In the arc forming process,use CMT Advanced 4000 digital welding machine,using the pulse mode for welding,helium argon mixed gas is used for gas protection,the best overlap rate of 50%.It was found by orthogonal welding test that the welding parameters are selected when the welding speed is 300 mm/min,the wire feed speed is 7.2 m/min and the 5% arc length correction,the obtained weld bead topography and surface quality are the best.In the side milling process of arc formed TC4 titanium alloy thin-walled parts,the milling force decreases as the milling speed increases,milling force increases with increasing per tooth feed and radial depth of cut,The increase in the above three parameters will cause the milling temperature to rise,and the milling speed has the greatest effect on milling temperature.Compare milling force with the change trend of forming precision,the milling force is the main factor influencing the forming precision during the milling process,and increasing the milling speed reduces the milling force to improve the forming accuracy.Bye the arc forming thin-walled parts and ordinary standard forging comparison test,found that the arc forming thin-walled parts of the milling force and milling temperature is higher,milling deformation is small and forming precision is better because of its elastic modulus larger.Study on surface integrity of arc forming TC4 titanium alloy thin-walled parts,using response surface method establish a prediction model of surface roughness of TC4 titanium alloy thin-walled parts,the prediction error of the model is less than 5% and have higher accuracy,using this prediction model can optimize milling parameters to improve surface quality.By studying the microhardness of the surface after forming,it was found that the hardening degree of TC4 titanium alloy thin layer was about 7%,hardening layer depth between 40-50 um,work hardening degree is small.