| 摘要 |
PURPOSE:To prevent the cracking of a composite roll consisting of an outer layer having a martensite matrix structure and an inner layer having a pearlite matrix structure by subjecting the outer layer to martensitic transformation in two stages. CONSTITUTION:When a composite roll consisting of an outer layer having a martensite matrix structure and an inner layer having a pearlite matrix structure is heat treated, cooling for hardening is stopped once at the Ms point - ordinary temp., heating to 400-800 deg.C is carried out and cooling is restarted. Since martensitic transformation is carried out in two stages, the transformation is accelerated and the internal stress is relieved to prevent the cracking of the composite roll. |
