金属热处理 ›› 2021, Vol. 46 ›› Issue (8): 105-108.DOI: 10.13251/j.issn.0254-6051.2021.08.020

• 工艺研究 • 上一篇    下一篇

回火温度对高性能耐火钢组织和性能的影响

张开广1, 童明伟1, 易勋2   

  1. 1.宝山钢铁股份有限公司 中央研究院, 湖北 武汉 430080;
    2.宝武集团鄂城钢铁有限公司, 湖北 鄂州 436008
  • 收稿日期:2021-04-05 出版日期:2021-08-25 发布日期:2021-12-09
  • 作者简介:张开广(1979—) ,男,高级工程师,硕士,主要研究方向为建筑及海洋工程用钢产品研发,E-mail:zhkg001@baosteel.com
  • 基金资助:
    国家重点研发计划(2018YFC0705500)

Effect of tempering temperature on microstructure and mechanical properties of a high performance fire-resistant steel

Zhang Kaiguang1, Tong Mingwei1, Yi Xun2   

  1. 1. Central Research Institute of Baoshan Iron and Steel Co., Ltd., Wuhan Hubei 430080, China;
    2. Baowu Iron and Steel Group Echeng Iron and Steel Co., Ltd., Ezhou Hubei 436008, China
  • Received:2021-04-05 Online:2021-08-25 Published:2021-12-09

摘要: 利用光学显微镜、透射电镜、力学性能测试等方法,研究了回火温度对某高性能耐火钢组织和性能的影响。研究表明,回火后试验钢均表现出良好的高温性能和强韧性匹配,650 ℃回火时试验钢的耐火性能和低温冲击性能达到最优。回火前后试验钢的组织以多边形F+板条/粒状B为主,含有少量M/A岛,且有较多近似球形或椭圆形碳化物或复合碳氮化物析出。随着回火温度的升高,组织稍有粗化,部分板条B合并变成胞状结构,M/A岛数量及形态变化不大,但有效尺寸略有减小,600 ℃回火后析出相增加,650 ℃和680 ℃回火后有大量尺寸在50 nm以下的第二相质点析出,进一步确保了试验钢的耐火性能和低温冲击性能。

关键词: 耐火钢, 回火温度, 组织, 力学性能

Abstract: Effect of tempering temperature on microstructure and mechanical properties of a high performance fire-resistant steel was studied by means of optical microscope, transmission electron microscope and mechanical property test. The results show that the tested steel shows good high temperature performance and good match of strength and toughness after tempering, and the fire-resistance and low temperature impact property reach to the optimum when tempered at 650 ℃. Before and after tempering, the microstructure of the tested steel is mainly polygonal F+lath/granular B, and with a small amount of M/A islands, as well as many approximately spherical or elliptical carbides or complex carbonitride. With the increase of tempering temperature, the microstructure slightly coarsens, and some lath B merges into cellular structure. The M/A islands change little in number and morphology, though their effective size slightly decreases. After tempering at 600 ℃, the quantity of precipitated phases increases, and a large number of second phase particles with size below 50 nm precipitate when tempered at 650 ℃ and 680 ℃, which further ensures fire-resistance and low temperature impact property of the tested steel.

Key words: fire-resistant steel, tempering temperature, microstructure, mechanical properties

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