Process: Heat to 900–950°C (austenitization), hold, then air-cool.
Effect: Refines ferrite-pearlite microstructure, eliminates rolling segregation. Improves 0°C impact energy by 25–40% (from 27J to 35–38J), ideal for thick plates (>16mm).
Process: Normalize first, then reheat to 550–650°C, hold, and air-cool.
Effect: Further relieves residual stress while retaining fine microstructure. Boosts 0°C impact energy by 50% (to 40–45J), suitable for welded structures.
Process: Controlled rolling (1100–1200°C) + reheating to 750–850°C.
Effect: Creates ultra-fine ferrite, raising 0°C impact energy to over 50J. Used for high-performance low-temperature applications.
Process: Heat to 550–600°C, hold, then slow-cool.
Effect: Reduces residual stress (critical for welded/machined parts) without altering microstructure, preventing stress-induced brittle fracture.
