非晶态镍基钎料箔润湿成缝特征及其对钎焊接头形态的影响

通过分析控制非晶态镍基钎料箔用量的钎焊试验结果,对非晶态镍基钎料箔的润湿成缝特征及钎焊接头形态进行了研究.结果表明,即使在钎料不足的情形下,钎料残余层也始终存在,在熔融钎料同母材的相互作用下,钎料残余层/母材界面向母材一侧发生迁移;钎料残余层厚度随钎料量的增加而增大,但界面迁移深度与钎料箔大小无关.熔融钎料成缝行为遵循能量最低原理,其受自身重力、粘滞力和表面张力引起的附加压力共同作用,流动成缝时具有粘性流体的特征,贴近母材表面的边界层流速趋缓,母材向熔融钎料中的溶解则进一步降低了其流动性,最终凝固形成钎料残余层.

Wetting and joint-formed characteristics of amorphous Nibased filler metal foil and its influence on brazed joint formation

The control of the amount of amorphous nickelbased filler metal foil was analyzed,and the wetting and jointformed characteristics of the amorphous nickel-based filler metal foil and brazed joint formation were studied.The results showed that the filler metal residual layer always exists after the brazing process with amorphous nickel-based filler metal foil,even when the filler metal is insufficient to fill in the joint.The migration of the interface between filler metal residual layer and base metal was observed,which was related to the interaction between molten filler metal and base metal.The thickness of filler metal residual layer increases with adding the filler metal foil,but the interface migration depth does not relate to the filler metal foil size.The joint-formed behavior of molten filler metal follows the minimum energy principle,the molten filler metal is affected by its own gravity,viscous force and the additional pressure are caused by surface tension,which flow into the seam with viscous fluid characteristics.The flow rate of liquid alloy in the boundary layer closing to steel surface gradually slows down,and the dissolution of base metal to the molten filler metal further reduces its fluidity.Finally the molten filler metal solidifies and the residual layer forms.