淬火工艺对Cr26高铬耐磨铸铁组织与硬度的影响  

Effect of quenching process on microstructure and hardness of Cr26 high chromium wear resistant cast iron

作　　者：梁秀娟 嵇海旭 Liang Xiujuan;Ji Haixu(School of Mechanical and Power Engineering,Guangdong Ocean University,Zhanjiang Guangdong 524000,China)

机构地区：[1]广东海洋大学机械与动力工程学院,广东湛江524000

出　　处：《金属热处理》2020年第4期141-143,共3页Heat Treatment of Metals

基　　金：广东省财政厅高校重大科研项目培育计划(GDOU2015050224);广东省自然科学基金(1614050000138)。

摘　　要：利用光学显微镜、洛氏硬度计等研究了不同淬火工艺对Cr26高铬耐磨铸铁组织与硬度的影响。结果表明:铸态Cr26高铬铸铁组织主要由初生奥氏体和碳化物组成。经980~1060℃不同温度淬火、空冷后,高铬铸铁组织中有大量二次碳化物析出。随着淬火温度的升高,析出的二次碳化物先增加后减少,试样硬度先升高后降低。1020℃淬火试样硬度达到峰值,为65. 7 HRC。1020℃淬火高铬铸铁,经空淬、油淬和水淬不同方式冷却,随着冷却速度的增大,高铬铸铁组织中碳化物颗粒、碳化物比例逐渐增大,硬度逐渐增大,其中水淬高铬铸铁试样硬度最大,达到68. 2 HRC。Effects of different quenching processes on the microstructure and hardness of Cr26 high chromium wear resistant cast iron were studied by means of optical microscope and Rockwell hardness tester. The results show that the microstructure of as-cast Cr26 high chromium cast iron is mainly composed of primary austenite and carbide. After quenching and air-cooling at different temperatures from 980 ℃ to 1060 ℃,a large amount of secondary carbides are precipitated from the microstructure of high chromium cast iron. With the increase of quenching temperature,the secondary carbides precipitated in the microstructure first increase and then decrease,and the hardness of the specimen first increases and then decreases. The hardness of quenched specimens at 1020 ℃ reaches peak value,which is 65. 7 HRC. When the high chromium cast iron quenched at 1020 ℃ in air,oil or water,carbide particles in the microstructure of high chromium cast iron,carbide proportion,and the hardness of the high chromium cast iron all increase gradually with the increase of cooling rate. The hardness of water quenched high chromium cast iron reaches the maximum value of 68. 2 HRC.

关 键 词：Cr26高铬铸铁 淬火 显微组织 碳化物 硬度 

分 类 号：TG143.9[一般工业技术—材料科学与工程]