回火工艺对厚规格NM450耐磨钢组织和硬度的影响  

Effect of tempering on microstructure and hardness of thick gauge NM450 wear-resistant steel slab

作　　者：姜金星 董俊媛 王慧慧[2] 吴翔 赵威威 左秀荣[2] Jiang Jinxing;Dong Junyuan;Wang Huihui;Wu Xiang;Zhao Weiwei;Zuo Xiurong(Nanjing Iron and Steel Co.,Ltd.,Nanjing Jiangsu 210035,China;School of Physics,Zhengzhou University,Zhengzhou Henan 450052,China)

机构地区：[1]南京钢铁股份有限公司,江苏南京210035 [2]郑州大学物理学院,河南郑州450052

出　　处：《金属热处理》2020年第1期117-121,共5页Heat Treatment of Metals

摘　　要：利用光学显微镜、扫描电镜和维氏硬度计研究了NM450耐磨钢在不同回火温度(200、250、300和350℃)和回火时间(160、190、220和250 min)下组织和硬度的变化规律。结果表明,淬火后钢板在厚度方向的硬度波动较大,在偏析带位置硬度明显高于其他位置。回火温度对NM450钢的硬度产生了非常显著的影响,回火后NM450钢的硬度出现了下降,尤其以偏析带处硬度下降最大。随回火保温时间增加,NM450钢的硬度没有明显降低。The microstructure and hardness of NM450 wear-resistant steel at different tempering temperatures( 200,250,300,and 350 ℃)and duration( 160,190,220,and 250 min) were studied by using optical microscope( OM),scanning electron microscope( SEM) and Vickers hardness tester. The results show that the hardness of the steel plate fluctuates greatly in the thickness direction,and the hardness is significantly higher in the segregation zone than in other locations. Tempering temperature has a very significant impact on the hardness of the NM450 steel. After tempering,the hardness of NM450 steel decreases,especially in the segregation zone. With the increase of tempering and holding time,the hardness of the NM450 steel does not decrease remarkably.

关 键 词：NM450耐磨钢 回火 硬度 偏析 

分 类 号：TG156.5[金属学及工艺—热处理]