Melting of Steel Inserts by Cast Iron Melt in Cast-in Insertion Bonding

摘要

In cast-in insertion bonding, inserts may melt and be damaged by excessive heat supply from the molten metal. To reveal the process and the conditions of insert melting, two experiments and numerical analysis were performed. Mild steel and ductile cast iron bars were dipped into gray iron melt held at constant temperatures. Cast-in insertion experiments on samples of the same materials at different diameters were also performed. Solidification and melting processes in these two experiments were simulated by the finite difference method. The simulation of the cast-in experiments showed two stages in the melting of steel inserts in a cast iron melt. The first stage melting is caused by the high temperature melt coming in contact with the inserts, and the second stage is due to a longer period of carburization of the insert at a temperature just above the eutectic point of cast iron. To prevent inserts being damaged by melting in the cast-in insertion process, it is necessary to suppress the first stage of melting.