高铬铸铁热电偶保护管铸造工艺.pdf

学兔兔 NOV．2011 铸 造 V0 60 NO．11 FOUNDRY ·1141· 高铬铸铁热电偶保护管的铸造工艺 薛志勇 ，陈雨峰 ，马明珠 ，张小燕 (1．华北电力大学电站设备状态监测与控制教育部重点实验室，北京102206；2．江苏奥玛德新材料科技有限公司 江苏盐城224000；3．方正科技集团股份有限公司，北京100871) 摘要：从化学成分、铸造工艺入手，采用熔模精密铸造工艺，成功制备出表面 屺洁度好，性能优良，适合批量生产的 高铬铸铁热电偶保护管。对比了用不锈钢管、石墨芯棒和石英管做芯管 (芯棒)进行浇注的优缺点，发现用石英管做 芯管制备的保护管表面光洁，成本低，工艺成品率高。所制备的保护管硬度为HRC 58．7，组织中存在呈菊花放射状的 锥体形状的碳化物，碳化物以紧密的纤维状分布在基体中，X衍射发现存在大量的 (Fe，Cr)7C，，出现这种化合物会使 铸件的耐磨性能提高。 关键词：高铬铸铁；热电偶保护管；熔模铸造；组织性能 中图分类号：TG24 文献标识码：B 文章编号：1001—4977(201 1)1 1—1 14104 Casting Technology for Thermocouple Pr’otection Tubes of High Chrome Cast I ron XUE Zhi．yong’，CHEN Yu。feng ，MA M g—zhu1，ZHANG Xiao．yan0 (1．North China Electric Power University，Key Laboratory of Condition Monitoring and ControI for Power Plant Equipment，Ministry of Education，Beijing 1 02206，China；2．New Materials Technology Co．，Ltd．，Jiangsu Amorphd，Yancheng 224-000，Jiangsu，China； 3．Founder Technology Group Corp．，Beijing 100871，China) Abstract：Thermocouple protection tubes of high chrome cast iton with good surface finish and suitable for mass production have been successfully~nade by jnvestment casting process．The advantages and disadvantages of core tube(rod)of stainless steel，graphite and quartz tubes were analyzed and resuIts show that protection tubes with quartz core rod have smooth surface．1OW cost．high process yield．The hardness of protection tube iS HRC 58-7．The pyramidaI shape carbides were found in the microstructure．A Iarge number of compounds(Fe，Cr)7C3 were found by X-ray di仟raction．which can improve the wear resistance of castings．