硬质合金与钢电子束焊接接头组织及性能  

Microstructure and mechanical properties of cemented carbide to steel joints by electron beam welding

作　　者：陈国庆[1] 张秉刚[1] 吴振中[1] 何俊[2] 冯吉才[1] 

机构地区：[1]哈尔滨工业大学先进焊接与连接国家重点实验室,哈尔滨150001 [2]兰州空间技术物理研究所,兰州730000

出　　处：《焊接学报》2013年第6期9-12,113,共4页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(51075089);973国家重点基础研究发展计划资助项目(2010CB731704)

摘　　要：通过预置镍基金属填充层进行了硬质合金与钢的偏钢侧电子束焊接,获得了无裂纹缺陷的焊接接头.焊接接头为"半钉形"熔-钎焊接头,硬质合金/焊缝界面及钢/焊缝界面均形成了较好的冶金结合,且硬质合金母材发生微熔,部分WC颗粒进入焊缝中.结果表明,硬质合金侧界面处获得了γ(Fe,Ni)固溶体组织和以W2C及Fe3W3C为主的"鱼骨状"碳化物组织,钢侧热影响区为典型的马氏体组织.焊缝中含有较多的Fe,Ni元素,且Ni元素向硬质合金侧界面处发生了扩散;接头最高抗拉强度可达560 MPa,最高抗剪强度达到460 MPa,断口为明显的准解理断口.Dissimilar materials joints without macroscopic cracks were obtained between cemented carbide and steel by electron beam welding inclined to steel with Ni-based filling layer.The joints were fusion-brazed in shape of 'half-nail',and solid metallurgical bonding was obtained at the hard alloy/weld interface and the steel/weld interface.Micro-melting of hard alloy base metal occurred and some WC particles diffused into the weld.Microstructure analysis of the weld revealed that γ(Fe,Ni) solid solution and 'herringbone' carbides mainly composed of W2C and Fe3W3C formed in the interface on hard alloy side,and martensite formed in the heat-affected zone of steel.The weld mainly consisted of Fe and Ni,and Ni diffused towards the interface on hard alloy side.The maximum tensile strength of the joint was 560 MPa and the maximum shearing strength was 460 MPa with features of quasi-cleavage fracture.

关 键 词：硬质合金 钢 填充层 电子束焊接 

分 类 号：TG456.3[金属学及工艺—焊接]