The simple heat treatment process is another important advantage of maraging steel.
After hot working, Maraging300 shall undergo solution treatment before cold working and aging strengthening. The purpose is to dissolve the remaining sediment after hot processing; Dissolve the matrix with sufficient strengthening elements; The uniform martensitic structure with high dislocation density was obtained.
The solution temperature is usually 820~840 ℃, the solution time is 1h per 25ram thickness, and the cooling rate has little effect on the structure and properties after solution. The high strength of maraging steel is obtained by aging treatment. The aging temperature is generally 480 ℃, and 510 ℃ can be used for steel with high strength grade. The aging time is 3~6h, and the air cooling after aging.
After aging, a large number of dispersed and ultra-microscopic intermetallic compound particles are precipitated on the martensite matrix, which makes the strength of the material double and the toughness loss is small.
