基于焊接力开环及闭环模式交互作用的摩擦焊接技术研究

基于焊接力开环模式及闭环模式交互控制方式，研制摩擦焊机轴向加载液压系统，实现对焊接辅助过程、三级摩擦焊接过程中轴向焊接力的控制。从辅助过程到自动焊接过程，轴向力的变化经历了七个阶段:在辅助过程中，开环模式控制下的轴向力对摩擦焊接缩短量及工件焊后尺寸精度无明显影响;在三级摩擦焊接过程中，闭环模式控制下的轴向焊接力的控制精度、稳定性对摩擦焊接轴向缩短量及工件焊后尺寸精度具有直接和间接的影响。基于焊接力开环模式及闭环模式交互控制方式研制的轴向摩擦焊机，可实现材料为40Mn2、型号为XDZ190支重轮摩擦焊，焊接接头成形良好，工件的摩擦焊接缩短量精度控制在0～0.5 mm以内。

Friction welding technology based on open-loop and closed-loop mode of welding force

Based on the open loop mode and closed loop mode interactive control of welding force,the axial loading hydraulic system of friction welding machine was developed to control the axial welding force in the auxiliary welding process and three-stage friction welding process.From the auxiliary process to the automatic welding process,the change of axial force goes through seven stages.The axial force under the control of open-loop mode has no obvious influence on the reduction of friction welding and the size accuracy of workpiece after welding in the auxiliary process;In the three-stage friction welding process,the control accuracy and stability of the axial welding force under the closed-loop mode control have a direct and indirect influence on the axial reduction of friction welding and the dimension accuracy of the workpiece after welding.The axial friction welding machine developed based on the welding force open-loop mode and closed-loop mode interactive control mode can realize the friction welding of 40 Mn2 material and XDZ190 supporting heavy wheel,the welded joint is well formed,and the reduction precision of the friction welding of the workpiece is controlled within 0~0.5 mm.