The tendency of large forgings to become more brittle is due to the precipitation of temper brittle carbides or the aggregation of harmful trace elements such as phosphorus, tin, antimony, and arsenic along grain boundaries.

The solution to prevent temper embrittlement of large forgings is

1. Reduce the content of harmful elements in forging steel;

2. Reduce segregation in forging steel;

3. Avoid heat treatment in the temper brittle temperature zone and perform appropriate rapid cooling to prevent the enrichment of harmful groups.