利用连续载荷和冲击载荷实现碳钢的摩擦冷压焊封孔焊接

Hole Sealing of Carbon Steel by Friction-drive Cold Pressure Welding Under Continuous Pressing and Impact Pressing Loads

设计了一种通过摩擦驱动的冷压焊实现碳钢封孔的焊接方法。填充金属设计为锥形，并设计与锥头相配合的锥孔。因此，冷压焊机制预计通过材料表面相互摩擦。达到粘着摩擦机制得以形成。实验中使用了连续载荷和冲击载荷进行封孔焊接，并根据所建立的力学模型，设计压人深度。焊后对试样进行了去应力退火，对接头进行剪切强度测试，用光镜对接头的组织形貌进行分析。结果表明：连续载荷单侧变形区厚度为20μm，冲击载荷为80μm。接头在连续载荷作用下由于疲劳的影响，不可避免地在结合面之间产生小颗粒。阻碍界面接合。而在冲击载荷作用下形成波浪型焊缝，部分原始界面相互融合．表明冷压焊机制已经形成。接头剪切强度达到母材50%-65％，在工程上有良好的应用前景。

A friction-drive cold pressure welding method was designed for hole sealing of carbon steel. The filler metal was shaped as a cone and pressed into the hole that was cone shaped as well. Thus, cold welding mechanism was expected by the surface relative motion in stick mode, which was driven by the surface friction. Two kinds of loads （continuous pressing load and impact pressing load） were used for hole sealing in the experiments. The press-in depth was designed based on the calculation of the established mechanical model. After welding, the samples were annealed to release elastic strains and prepared for shear strength test and microstructure observation. The results show that the thickness of the surface deformations on one side is around 20 μm by continuous pressing load and 80 μm by impact pressing load. By continuous pressing load, owing to the fatigue effect, wear dusts are inevitably formed between the laying surfaces, which hinders the surfaces bonding. By impact pressing load, wavy bonding line is formed which is composed of streamlines and a part of original interfaces coalesce indicating that a cold pressure welding mechanism has been formed. The shear strength of the joint reaches 50% -65% of the base metal showing favorable application in engineering.