Simulation of Heat Treatment Pressure Straightening and Traightening-Force Prediction Model of TC4 titanium Alloy Airframe Elliptical Hole Bulkhead

There is great engineering significance to predict the heat treatment pressure traightening force of titanium alloy airframe bulkhead for improving the traightening effect of the airframe bulkhead. The traightening-force and traightening-amount of TC4 titanium alloy airframe elliptical hole bulkhead during heat treatment pressure traightening process were simulated utilizing the ANSYS finite element numerical simulation software. The influence of elliptical hole sizes on the traightening-force of the bulkhead was analyzed, and the traightening-force prediction model considering elliptical hole size was developed by using a nonlinear regression method. The results show that, as thetraightening-force increase , the traightening-amount initially rises slowly, then increases rapidly, and finally slows down again. The traightening-force decreases nonlinearly with the increasing of the axial length a or b of the elliptical hole, with a more pronounced effect observed for axial length a compared to axial length b. The developed traightening-force prediction model with a correlation coefficient R of 0.993 24, exhibits the high prediction accuracy, and can accurately predict the traightening-force of TC4 titanium alloy airframe elliptical hole bulkhead during heat treatment pressure traightening process .