METHOD OF HEAT TREATMENT OF ARTICLES MADE FROM HIGH-TEMPERATURE DEFORMABLE PRECIPITATION HARDENING NICKEL-BASED ALLOYS

摘要

FIELD: metallurgy; heat treatment of articles made from high-temperature deformable precipitation hardening nickel-based alloys.;SUBSTANCE: proposed method includes hardening and stepped aging; hardening is performed at temperature which is higher than T_c.dis.γ by 30-100°C; holding at this temperature is continued for at least 5 min and is followed by cooling in air; stepped aging is performed at three stages: at first stage heating is performed to temperature which is below temperature T_c.dis.γ by 50-100°C and holding is continued for at least 2 h and is followed by cooling in air; at second stage, heating is performed to temperature 770-860°C and holding at this temperature is continued for at least 5 h and is followed by cooling in air; at third stage heating is performed to temperature of 660-750°C and holding at this temperature is continued for at least 10 h and is followed by cooling in air; T_с.dis.γ is temperature of complete dissolving of γ-phase.;EFFECT: high level of short-term and long-term strength, plasticity, impact viscosity; reduced sensitivity to stress concentrators; enhanced structural stability in welded units; improved weldability.;1 tbl, 1 ex