Factors affecting the holding time of the workpiece in the experimental electric furnace

1. Heating temperature

Under normal circumstances, empirical data is often used for calculation in experimental electric furnaces. For example, carbon steel is usually calculated at 1min/1mm, while alloy steel is 1.3 to 1.8 times that of carbon steel. The reason is that alloy steel has a high content of alloying elements. But at high temperature (1000℃), if the effective thickness is large, the lower limit of this coefficient is used, and the upper limit of the effective thickness is small.

2. Differences in steel grades

For carbon steel and low alloy steel, the time required for dissolution of carbides and homogenization of austenite is very short, so according to the situation, “zero” heat preservation quenching can be used, which can shorten the process cycle and reduce Quenching cracks. For high-alloy steel, the quenching heating and holding time should be appropriately extended to ensure the dissolution and austenitization of carbides. It can be estimated at 0.5 to 0.8min per millimeter for the holding time. When the upper limit of the quenching temperature is 0.5min, the quenching temperature depends on Take 0.8min at the lower limit.