A surface hardness control method and production method for large-size cutting non-quenched round steel
By controlling the residual heat of hot-rolled round steel and using surface induction heating technology, the surface microstructure of large-size non-quenched and tempered steel is transformed into pearlite and ferrite, solving the problem of excessive surface hardness and achieving improved cutting performance and reduced energy consumption.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- JIANGSU LIANFENG ENERGY EQUIP
- Filing Date
- 2026-06-10
- Publication Date
- 2026-07-17
AI Technical Summary
Excessive surface hardness in large-scale machining of non-quenched and tempered steel leads to accelerated tool wear and reduced machining efficiency, and existing stress-relief annealing methods have limited effectiveness.
By utilizing the residual heat of hot-rolled round steel to control the surface reddening temperature and surface induction heating process, the surface layer is austenitized through induction heating and then air-cooled to a pearlitic and ferritic structure, thereby reducing the surface hardness.
It effectively reduces surface hardness to 250~300HBW, improves machinability, and maintains the mechanical properties of the material while reducing energy consumption.
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Figure CN122405947A_ABST