摩擦叠焊单元成形过程分析

借助高速摄像机拍摄典型的圆柱形塞棒+圆柱形孔的摩擦叠焊单元成形摩擦液柱成形(Friction hydro pillar processing,FHPP)完整过程,观察塞棒与孔的红热状态和外观变化,还将本试验的FHPP焊接过程按塞棒消耗量由短到长进行分段焊接,制作各分段单元纵切面试样。将采集的焊接过程参数变化曲线与高速摄像图片以及各分段焊接单元的焊接试样剖面图进行对比分析,针对各参数以及焊接过程单元形貌随时间的变化,将焊接过程划分为焊前、焊接、保持三个阶段。焊接过程各参数有相应波动,尤其扭矩波动较大。研究发现焊接过程产生不连续的摩擦剪切面,摩擦剪切面不断"产生-压溃-挤出",完成摩擦叠焊单元的成形。摩擦挤出物可分为塞棒飞边与母材飞边两部分。

Procedure Analysis of Friction Hydro Pillar Processing

A whole forming process of friction hydro pillar processing (FHPP) with the rod and hole of cylindrical shape is filmed by a high-speed camera for observing the red-hot state and appearance changes. The welding process of FHPP is divided into several segments of welding respectively according to the rod consumption and the welds of each of these segments are made into longitudinal section specimens. A synchronized analysis is done on basis of the curves of the welding parameters, high-speed camera images and longitudinal sections of each subsection welding unit. The welding process is divided into pre-welding, welding and holding stages according to the parameter curves and the states of the units. All of the welding parameters especially the torque fluctuate during the welding process. It is discovered that a series of discontinuous friction shearing layers are generated during the welding process and these friction shearing layers are constantly “generated-collapsed-squeezed out” to form the friction stitch welding unit. The material squeezed out can be divided into two parts named rod flash and base metal flash.