摘要
设计和制备了一种稀土高铬镍氮多元合金耐热铸钢材料,探讨了回火工艺对该材料组织结构和力学性能的影响规律。结果表明:制备的合金在铸态下金相组织主要由奥氏体和碳化物组成,其中,碳化物的形态较粗大,具有明显的方向性,且呈现连续网状分布。当回火温度在280~520℃范围变化时,随着回火温度的升高,组织中二次碳化物逐渐析出,在回火温度为480℃时,二次碳化物的数量最多,形态更为细小,由于二次碳化物呈颗粒状,从而造成的应力集中少,细小、弥散分布的二次碳化物割断了共晶团的连续生长,从而细化了晶粒。因此,力学性能在此温度条件下得到良好的配合。研究结果还表明:随着回火温度的升高,280~480℃区间内,材料的硬度逐渐减小,冲击韧度逐渐增大,但是硬度和冲击韧度变化的幅度不大。当回火温度大于480℃时,材料的硬度减小幅度较大,冲击韧度增大趋势明显。
In this paper, a rare earth high Cr-Ni-N multicomponent alloy heat resistant cast steel was designed and prepared, and the effects of tempering process on the microstructure and mechanical properties of the material was discussed. The results show that the metallurgical structure of the prepared alloy is mainly composed ofaustenite and carbides with larger shape, obvious directivity, and continuous net distribution. When tempering temperature varies from 280 ℃ to 520 ℃, secondary carbides gradually precipitate with the increase of the tempering temperature. At tempering temperature 480 ℃, the number of secondary carbides is the most and the morphology is the finest. As the secondary carbides are granular, the stress concentration is less, and fine and dispersed secondary carbides cut off the continuous growth of eutectic cells clusters and refined the grains. Therefore, the mechanical properties are well matched at this temperature. The results also show that with the increase of tempering temperature, the hardness of the material decreases gradually and the impact toughness increases gradually from 280 ℃ to 480℃, but the magnitude of the change is small. When the tempering temperature is more than 480℃, the hardness of the material decreases greatly and the impact toughness increases obviously.
作者
姜利坤
李东玮
崔晓丽
亢同庆
徐娜
JIANG Li-kun1,2, LI Dong-wei1, CUI Xiao-li1, KANG Tong-qing2, XU Na3(1. Qilu University of Technology, Advanced Materials Institute, Shandong Academy of Sciences, Jinan 250014, Shandong, China; 2. Boiler Accessories Manufacturing of Shandong Yuanda Co., Ltd., liaocheng 252428, Shandong, China; 3. Qilu University of Technology, Shandong Analysis and Test Center, Jinan 250014,Shandong,Chin)
出处
《铸造》
CAS
CSCD
北大核心
2018年第3期252-256,共5页
Foundry
基金
山东省自然科学基金(ZR2017BEM004,ZR2017BEM020).
关键词
高铬镍氮合金铸钢
回火工艺
奥氏体
二次碳化物
high Cr-Ni-N alloy cast steel
tempering process
austenite
secondary carbide
