一种用于碳化钨堆焊的管装电焊条的研究

A NEW TYPE TUNGSTEN CARBIDE TUBULAR WELDING ELECTRODE

提供一种用于碳化钨堆焊的管装电焊条。扫描电镜观察、能谱分析及显微硬度测试结果表明堆焊层中存在两种类型的硬质相 ,即 WC- W2 C共晶的原始碳化钨颗粒(硬度 HV2 0 12～ 2 34 1)和 M6C构成的 η相 (HV1817～ 2 2 14)。M6C相以粒状和团块状存在 ,与实芯焊条堆焊的金属中析出的鱼骨状共晶 M6C相比较 ,在不降低堆焊层硬度条件下 ,可提高堆焊层的强度和韧性指标。新型焊条中使用 D型热绝缘剂 ,减少了原始碳化钨颗粒的熔损 ,使焊缝金属组织中硬质相分布域直径 Dd 和面积分数 AC 分别提高2 5 %和 6 2 %。

A new type tungsten carbide tubular welding electrode was designed for improving the wear resistant of bead welding layer with manual metal arc welding. The results of SEM, ESCA and measured microhardness show that two type hard phase exist in the bead welding layers, one was the original particles of WC-W 2C eutectic carbide with microhardness HV 2012~2341, and the other was η phase composed of M 6C carbide with HV 1817~2214. The granular or massive structure of M 6C is more favourable to the strength and toughness of the bead welding layers than the fishbone structure of M 6C eutectic carbide formed in the conventional tungsten carbide arc bead welding with solid welding electrodes. The inner heat protection technology and D-type heat insulator have been used for reducing corrosion of tungsten carbide particles during the bead welding process, and the distribution range diameter Dd and area fraction Ac of hard phase particles in bead welding layers increased by 25% and 62% respectively.