非调质钢的发展概况与其特征的变化

全面地描述了非调质钢的发展概况，分析了非调质钢发展过程中化学成分、加工工艺、显微组织、强化机制、性能、应用范围、品种规格等方面特征的变化。在４９ＭｎＶＳ３钢的基础上降碳、提锰、增硅，采用复合微合金技术的非调质钢、冷作强化非调质钢、贝氏体型非调质钢的生产应用量最大，为了进一步改善非调质钢的韧性，应用了温锻工艺、氧化物冶金技术、锻热淬火技术。

DEVELOPMENT OF NON-QUENCHED AND TEMPERED STEEL AND CHANGE IN ITS CHARACTERISTICS

The development of the non-quenched and tempered steel is fully summerized. A detailed investigation is made into its change in characteristics with development, ie., the chemical composition, manufacturing process, micro-structure, strenthening mechanism, properties, applications, grades and specifications. The complex micro-alloyed, cold strenthened, and bainitictype modified steels enjoy the widest and most applications, Based on the 49MnVS3 Steel, these steels are produced by lowering carbon, increasing manganese and silicon. To further improve toughness of the non-quenched and tempered steels, the warm forging, oxide metallurgy and forging residual heat quenching technologies are adopted.