Ti和Ti／Ni／Ti连接钨与铜及其合金的界面结合机制与接头强度

采用热 力学模拟试验机Gleeble1500D作加热设备,用Ti片和Ti箔 Ni片 Ti箔复合中间层扩散连接钨与铜及铜合金CuCrZr。结果表明,当用Ti片连接钨与铜,连接温度下Ti与Cu反应但未转化成液相时,则反应层由具有一定脆性的多层化合物组成,接头强度偏低;当Ti片通过共晶反应转化成液相且大部分液相被挤出连接区时,接头强度显著提高,最高达220MPa。用Ti Ni Ti复合中间层连接钨与CuCrZr时,结合界面是通过Ti分别与Ni、W及Cu相互扩散并反应生成多层化合物和固溶体而形成的;与Ti片连接钨与铜的接头形成相似,连接过程中Ti箔未转化成液相时接头强度偏低,Ti箔转化成液相时接头强度明显提高。

Interfacial bonding and strength of tungsten to copper or its alloy joints with Ti foil and Ti/Ni/Ti multiple interlayers

Ti foil and Ti/Ni/Ti multiple interlayers were selected for the bonding of tungsten to copper or CuCrZr alloy with thermal-mechanical simulator Gleeble 1500D. The effects of technology parameters on the microstructures and shear strength of the joints were performed. The interfacial bonding mechanism was studied through microanalysis. When Ti foil was used for bonding of tungsten to pure copper but not transformed into liquid solution during the holding time, a reaction zone including multiple compound layers with brittleness was formed and the strength of the joints was lower. However, if the Ti foil was transformed into liquid solution and extruded mostly out of the bonding zone, the strength of the joints can reach 220MPa due to the chemical and mechanical interfacial bonding. The joint was formed through the diffusion and reaction among the Ti, Ni, Cu and W to form multiple compound layers and solid solution layers when Ti/Ni/Ti was used for bonding tungsten to CuCrZr alloy. Similarly, if Ti foil was transformed into liquid solution, a strong joint can be obtained, otherwise, the strength was relatively low.