Transactions of Materials and Heat Treatment

Title：Influence of forging and heat treatment on the microstructure and property of steel 20CrMoH

Authors： Sui Xiaoli

Unit： Changzhou Institute of Light Industry Technology

KeyWords： steel 20CrMoH forging ratio heat treatment linkage control system

ClassificationCode：TG316

year,vol(issue):pagenumber：2015,40(9):7-10

Abstract：

For the issues of gear design and manufacturing with gear material 20CrMoH used in the gearbox of electric vehicles and construction machinery, the influences of forging and heat treatment process on the microstructure and mechanical properties of gear steel 20CrMoH were studied. A series of experiment analysis and research of steel 20CrMoH were set up on forging with pre-heat treatment, carburizing and quenching by means of the linkage control system. The results show that it can eliminate the banded structure can be eliminaled and the material microstructure and mechanical properties of steel 20CrMoH can be effectively improve when the forging ratio is controlled less than 4, the upsetting forging ratio is more than or equal to 1.5 and the stretching ratio is less than or equal to 2.5. The good metallographic structure, mechanical properties and reasonable hardness gradient distribution can be obtained when the best normalizing temperature range is 890-930 ℃, the carbon potential of diffusion of direct quenching after carburizing and double quenching is 0.70%-0.85%, and the strong expansion ratio is 1∶1, which can meet the quality requirements of steel 20CrMoH gear parts.

Funds：

江苏省高等职业院校高级访问工程师计划资助项目（2013FG015）

眭小利（1970－），女，本科，副教授，高级工程师

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