摘要
为了解决铲齿使用寿命短的问题,对新型贝氏体组织铲齿用钢及其热处理工艺进行了研究。通过火花直读光谱仪和热膨胀仪检测了贝氏体钢的化学成分和相变点,采用正交试验的方法研究了正火温度、回火温度、回火时间对贝氏体钢韧性的影响,确定了最优的热处理工艺,借助扫描电镜(SEM)、Image-J软件、X射线衍射仪(XRD)及数显显微硬度仪等检测了铲齿用贝氏体钢的组织和组织中相组成比例以及其硬度。研究结果表明贝氏体铲齿用钢在热处理过程中影响冲击性能最主要的因素为正火温度,其次为回火温度、最后为回火时间,得到的最优热处理工艺制度为1080℃正火后在250℃回火90 min,此热处理条件下贝氏体钢具有良好的韧性(18.45 J)和硬度(46.85 HRC)结合,其组织中马氏体含量为23.985%,残留奥氏体含量为9.850%。
In order to solve the problem of short service life of shovel teeth,the new bainitic steel and its heat treatment process were studied.The chemical composition and phase transition points of the bainitic steel were tested by spark direct reading spectrometer and thermal dilatometer.Effect of normalizing temperature,tempering temperature and tempering time on the toughness of the bainitic steel was studied by orthogonal test method,and the optimal heat treatment process was determined.Microstructure,phase composition ratio and hardness of bainitic steel for shovel teeth were measured by means of scanning electron microscopy,Image-J software,X-ray diffractometer and digital microhardness tester.The results show that the most important factor affecting the impact toughness of the bainitic steel is the normalizing temperature, then the tempering temperature and the tempering time in order.The optimal heat treatment process is normalizing at 1080 ℃ + tempering at 250 ℃ for 90 min,by which the bainitic steel obtains a good combination of toughness( 18.45 J)and hardness( 46.85 HRC),and the content of martensite and retained austenite in the microstructure is 23.985% and 9.850%,respectively.
作者
郑丽丽
安胜利
彭军
张芳
高占勇
焦海东
Zheng Lili;An Shengli;Peng Jun;Zhang Fang;Gao Zhanyong;Jiao Haidong(College of Material and Metallurgy,Inner Mongolia University of Science and Technology,Baotou Inner Mongolia 014010,China;Inner Mongolia Autonomous Region Key Lal)oratory of Advanced Ceramic Materials and Devices,Baotou Inner Mongolia 014010,China)
出处
《金属热处理》
CAS
CSCD
北大核心
2020年第8期179-185,共7页
Heat Treatment of Metals
基金
国家自然科学基金(51874186,51664046,51664044)
内蒙古应用技术研究与开发计划(201802022)。
关键词
铲齿
贝氏体钢
热处理
组织
性能
shovel teeth
bainitic steel
heat treatment
microstructure
properties
