液-液复合制备灰铸铁-球墨铸铁双材料铸件的工艺研究

Study on Preparation of Gray-Iron/Ductile-Iron Casting by Liquid-Liquid Composite Casting

针对双液双金属复合铸造存在两种金属液混冲的问题,在复合界面处设置金属阻流网。通过灰铸铁-球墨铸铁双铁液浇注试验,研究了阻流网及相关因素对两种液体浇注时对流和扩散的影响,并研究了两种铸铁复合区组织及其与阻流网的结合。结果表明:设置阻流网能有效阻止两种金属液的混冲,在一定的浇注条件下,可把两种液态金属的对流、扩散区域控制在网孔附近;低碳钢材料的阻流网与铸铁之间形成冶金结合,阻流网的组织因铸铁中的碳向其扩散而改变;灰铸铁-球墨铸铁双材料之间由灰铸铁、球墨铸铁及阻流网三者冶金结合在一起。

In the liquid-liquid composite casting, the two metal liquid is easy to mix, so a metal barrier nets were installed between the two liquid metal interfaces. By the pouring experiment of gray iron/ductile iron, the effects of the barrier nets and the related factors were studied on convection and diffusion of the two liquids. And the structures of the two molten irons in the complex area and the combination with the barrier nets also were researched. The results show that the barrier nets could effectively prevent the two metals mixing and control the convection/diffusion zone in the vicinity of the mesh under the certain casting conditions; the metallurgical bonding between the low carbon steel barrier nets and the cast iron was formed and the structure of barrier nets were changed due to the diffusion of carbon in cast iron; the gray iron, ductile iron and the barrier nets joined together in the form of metallurgical bonding between the double materials of gray cast iron and ductile iron.