CAJ | 학술논문

通过在600,630,680,700和720℃保温1 h空冷,以及在630℃短时时效后炉冷和空冷的热处理,研究了不同时效温度,时效时间以及冷却方式对沉淀硬化马氏体不锈钢FV520B的组织和力学性能的影响.结果表明,630℃短时时效后钢中即可析出一定量的逆转变奥氏体,且钢中的析出相尺寸较小并弥散分布,由此提出了一种沉淀强化马氏体不锈钢的热处理工艺优化,即FV520B钢经630℃短时时效并炉冷后,可以获得较佳的高强度和高韧性组合.
통과재600,630,680,700화720℃보온1 h공랭,이급재630℃단시시효후로랭화공랭적열처리,연구료불동시효온도,시효시간이급냉각방식대침정경화마씨체불수강FV520B적조직화역학성능적영향.결과표명,630℃단시시효후강중즉가석출일정량적역전변오씨체,차강중적석출상척촌교소병미산분포,유차제출료일충침정강화마씨체불수강적열처리공예우화,즉FV520B강경630℃단시시효병로랭후,가이획득교가적고강도화고인성조합.
Low carbon martensitic precipitation hardening stainless steels are widely utilized in many engineering applications due to their high strength with reasonable toughness, ductility and corrosion resistance. However, those properties and their combinations are not always satisfactory to their users. For further improvement of the mechanical properties of these types of steels, a fundamen-tal understanding of the detailed microstructural features with various aging conditions is necessary. Therefore, the effects of aging temperature, aging time and cooling rate on the microstructure and me-chanical properties of a martensitic precipitation hardening stainless steel FV520B were investigated by OM, SEM, TEM and XRD methods. The results show that the steel aged at 630 ℃ for a short time and then furnace cooled, in which a typical lath martensitic with the proper amounts of reverse austenite and fined dispersed precipitates was observed, has a good combination of high strength and high toughness. It could be an optimized aging process for FV520B steel.