CY40镍基合金材质铸件的热裂纹解决措施  

Solution of Hot Crack in CY40 Nickel-based Alloy Castings

作　　者：陈香锦 黄汉敏 CHEN Xiang-jin;HUANG Han-min(Zhongshan Tiewang Fluid Control Equipment Co.,LTD.,Zhongshan 528427,Guangdong,China)

机构地区：[1]中山铁王流体控制设备有限公司,广东中山528427

出　　处：《阀门》2024年第10期1200-1204,共5页Chinese Journal of Valve

摘　　要：3英寸600磅级、材质为ASTM A494-CY40镍基合金材料的球阀阀体,在熔模铸造过程中和补焊过程中易产生热裂纹。通过合理地选择铸造工艺、调整熔炼、浇注和冷却的工艺参数、降低温度梯度和内部应力等方法减少热裂纹的发生,具体包括控制浇注温度、浇注速度和冷却速率,确保铸件均匀冷却。浇冒口设计可能造成铸件收缩时的热阻碍和机械阻碍,铸件在靠近内浇道的部位凝固较晚、冷却较慢;因此,铸件在此薄弱部位易引起热裂纹。若将内浇道分散,使金属液从几处进入型腔便可分散热应力,减少铸件收缩时的热阻碍和机械阻碍,防止或减少热裂纹的产生。在焊接过程中,严格控制焊接参数,如焊接温度、焊接速度和焊接电流,以减少热应力和热影响区的热裂敏感性。焊接方法、焊接材料有效地解决了材料的裂纹问题,并总结和固化了该材料行之有效的工艺操作要领。3-inch 600-lb ball valve bodies made of ASTM A494-CY40 nickel-based alloys are prone to thermal cracking during investment casting and repair welding.By reasonably selecting the casting process,adjusting the process parameters of melting,pouring and cooling,reducing the temperature gradient and internal stress,the occurrence of hot cracks is reduced,including controlling the pouring temperature,pouring speed and cooling rate to ensure uniform cooling of the casting.The design of sprue may cause thermal and mechanical hindrance during casting shrinkage,and the casting solidified late and cooled slowly near the inner sprue.Therefore,the casting is easy to cause hot cracks in this weak part.If the inner runner is dispersed,the metal liquid enters the cavity from several places to disperse the thermal stress,reduce the thermal obstruction and mechanical obstruction during the shrinkage of the casting,and prevent or reduce the generation of thermal cracks.During the welding process,welding parameters,such as welding temperature,welding speed and welding current,are strictly controlled to reduce thermal stress and thermal crack sensitivity in the heat affected zone.The welding method and welding material effectively solve the problem of cracks in the material,and summarize and solidify the effective process operation key points of the material.

关 键 词：镍基合金 焊接工艺 热裂纹 

分 类 号：TH134[机械工程—机械制造及自动化]