摘要
对用铁神一号净化剂净化孕育处理的灰口铸铁作了一系列用普通碳钢焊条焊接的试验:浇口棒的对接,铸铁板预热300℃、400℃堆焊以及铸铁板钻孔补焊。通过磁粉探伤或金相检验可以发现焊缝中是有微小裂纹的,就其形态而言,它们是晶间断裂,属结晶裂纹。并且在大多数焊缝熔合区内存在白口组织。白口组织和铸铁成分中碳、硫、磷含量高以及熔合区内铸铁熔液的快速冷却有关。用普通碳钢焊条与一般焊接工艺是很难避免裂纹的。然而,这种新型铸铁与普通灰口铸铁相比,有一定的塑性。表现为卷曲的钻屑和铸铁板堆焊时出现少量弯曲挠度。因此焊接时可产生一些变形,降低了焊接应力,从而减轻裂纹倾向,裂纹不明显。所以生产现场对这种新型铸铁已有用普通碳钢焊条焊补一些不要求机加工、致密性和刚度小的铸件的成功经验。
For the gray cast iron inoculated with Tie Shen Yi Nolinoculant series weld experiments were conducted using mild steel electrode as follow, butt joint of cast iron bars, deposit weld on preheated cast iron plate at 300 ℃ and 400 ℃, and repair weld for the holes in the cast iron plate. The microcrackings were detected in the weld by magnaflux testing and microscope examination. The detected microcrackings are the solidification cracking since they are the intergranular cracking, These crackings are related with high content of carbon, surphur, phosphorus in cast iron. It is difficult to avoid the cracks using mild steel electrode and common welding technologies. Besides, there is white eutectic structure in the fusion zone of most welds due to quick cooling of liquid cast iron. Compared to other gray iron, this cast iron inoculated with Tie Shen No.1 exhibits a little ductility because its drillings have a little curl shape and the welded cast iron plate shows a small curve due to deformation. When deformation happens the welding stress and tendency of crack are decreased. In practice the inoculated castings have been weld repaired successfully using mild steel electrode for the castings without needs of machining, high air compactness and high rigidity.
出处
《铸造技术》
EI
CAS
北大核心
2006年第9期910-913,共4页
Foundry Technology
关键词
新型孕育剂
灰口铸铁
焊接性
New type inoculated liquid
Gray cast-iron
Weldability
