复合电冶熔铸WC颗粒增强钢基复合材料的显微缺陷研究

Research of Microscopic Defects on WC Particulates Reinforced Steel Matrix Composites Prepared by The Composite Electroslag Melting and Casting

采用复合电冶熔铸工艺制备了WC颗粒增强钢基复合材料,该工艺具有高能球磨混粉均匀、电渣重熔精炼净化、电磁搅拌颗粒分散、水冷结晶逐层快速凝固等特点,熔炼过程中有利于气体排出、夹杂物的去除、WC颗粒的分散等,较好地解决了颗粒团聚和聚集问题.得益于较快的冷却速度,WC颗粒被钢液吞没,尽可能地避免了枝晶偏析,使晶粒得到细化.所制备的复合材料孔隙少、致密高、无夹杂,WC颗粒分布均匀,缺陷很少.

WC particulates reinforced steel matrix composites were prepared by the composite electroslag melting and casting technology,which has the characteristics of evenly blended high-energy ball-milling,refined and purified electroslag remelting,the dispersed particulates of the electromagnetic stirring,and the rapid step-by-step solidification by the water cooling crystallization.The smelting process is conducive to the snapout of gas,the removal of inclusions,and the dispersion of WC particulates.It can also solve the problem of agglomeration and aggregation.Thanks to the faster cooling rate,the WC particulates are swallowed by the liquid steel,which avoids the dendritic segregation as much as possible.Meanwhile,the grains get refined.The prepared composite material is less defective with the low porosity,high density,rare inclusion,and the evenly distributed WC particles.