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铸造工艺参数和细化剂对K4169合金枝晶组织、元素偏析、夹杂及缩松有明显的影响,浇注温度越低,一次枝晶主轴长度和二次枝晶臂距就越小,在同一浇注温度下,化学法细晶试样的一次枝晶主轴长度较普通铸造试样的短,但二者的二次枝晶臂距没有明显差别,晶粒细化后,合金中主要元素Fe,Cr,Nb,Mo和Ti的偏析减轻,晶粒的形态由树枝晶向细晶组织中的粒状晶转变,对晶粒球化现象做了合理解释,微量细化剂的加入不会在铸件中形成夹杂,不会改变合金的相组成,在高的浇注温度下,细化剂使晶粒细化的同时,也使铸件中的缩松大大减少。
Casting process parameters and refiner have obvious effect on the dendrite structure, element segregation, inclusion and shrinkage of K4169 alloy. The lower the pouring temperature is, the smaller the primary dendrite length and the secondary dendrite arm spacing are. In the same casting The primary dendrite length of the chemical fine grain sample is shorter than that of the ordinary casting sample at the temperature. However, there is no obvious difference in the secondary dendrite arm spacing. After the grain refinement, the main elements Fe, Cr , The segregation of Nb, Mo and Ti is reduced, the grain morphology changes from dendrite to granular crystal in the fine grain structure, and the grain spheroidization phenomenon is reasonably explained. The addition of the micro-refining agent will not be formed in the casting Inclusion does not change the phase composition of the alloy. At high pouring temperatures, the refiner makes grain refinement, while also greatly reducing the shrinkage in the casting.