添加铜中间层的钨真空扩散焊接研究

Study on Vacuum Diffusion Bonding Tungsten with Copper Interlayer

钨具备优良的物理化学特性,使其在国防军工等领域被广泛应用,但是普通焊接方式难以实现钨的可靠连接,限制了钨的应用。针对难熔金属钨高性能焊接制造的迫切需求,本工作采用铜箔作为中间过渡层,开展了W-W真空扩散焊接实验研究,详细研究了中间层厚度及轴向加载压力对接头力学性能的影响。利用电子万能试验机测试接头的剪切强度,并采用扫描电子显微镜、电子探针X射线显微分析仪分析观察扩散焊接头界面的微观组织、元素分布和断口形貌。结果表明:加入铜中间层可以实现W金属的可靠连接,增加中间层厚度可以使得W/Cu/W的结合界面接触更充分,更利于元素相互扩散,进而有利于提高接头的结合强度。

The excellent physical and chemical properties of tungsten make it widely used in the fields of national defense and military industry.However,it is difficult to achieve reliable connection of tungsten by common welding methods,which limits the application of tungsten.In order to meet the urgent demand of high-performance welding of tungsten,the W/W vacuum diffusion welding was carried out by using copper foil as the interlayer,and the effect of bonding pressure and thicknesses of copper interlayer on joint formation was investigated in detail.The shear strength of joint was tested by an electronic universal testing machine.The microstructure,element diffusion and fracture morphology of diffusion bonding interface were analyzed and observed by electron scanning microscope and electron probe X-ray microanalyzer.The results show that reliable connection of tungsten achieved by adding copper as interlayer.Increasing the thickness of the interlayer can make the contact of W/Cu/W bonding interface more fully,which is more conducive to the mutual diffusion of elements,and further improved the bonding strength of the joint.