摘要
利用预置Ti/Cr3C2复合粉末对H13模具钢进行了激光熔覆处理。通过SEM分析了不同粉末摩尔比下涂层的显微组织,讨论了涂层在干滑动磨损条件下的耐磨性及在800℃静态空气中的高温抗氧化性。XRD结果表明,复合涂层中主要物相为(Fe,Cr)固溶体和TiC、Cr7C3增强相。复合涂层室温(25℃)和高温(700℃)下的耐磨性较基体均有提高,相对耐磨性最低分别为3.68和3.79。800℃恒温氧化条件下具有较好的高温抗氧化性,氧化膜主要由Cr2O3和TiO2组成。Ti和Cr3C2摩尔比为2.44∶1时具有较好的耐磨性,摩尔比为2∶1时具有较好的高温抗氧化性。
In-situ Ti /Cr3C2 laser cladding coatings were fabricated on H13 hot die steel substrate with present of Ti/Cr3C2 composite powder.Microstructure of the composite coatings was investigated using SEM. Wear resistance of the composite coatings under dry sliding wear conditions and the high temperature( 800 ℃) oxidation resistance in still air were evaluated. XRD result shows that the main chemical composition are( Fe,Cr) solid solution and strengthening phases TiC and Cr7C3 carbide. Compared with H13 hot die steel substrate,the wear resistance of composite coating at room temperature( 25 ℃) and high temperature( 700 ℃) are obviously improved,and the minimum relevant wear resistance are 3. 68( 25 ℃) and 3. 79( 700 ℃),respectively. The oxidation resistance of all composite coatings under 800 ℃oxidizing conditions is enhanced significantly and the oxide films consist of Cr2O3 and Ti O2. When the molar ratio of Ti to Cr3C2 powder is2. 44∶1,the wear resistance is better,but when the ratio is 2∶1,the oxidation resistance is better.
出处
《金属热处理》
CAS
CSCD
北大核心
2015年第6期26-30,共5页
Heat Treatment of Metals
基金
国家自然科学基金(61368003)
关键词
激光熔覆
Ti/Cr3C2复合涂层
显微组织
耐磨性
高温抗氧化
laser cladding
Ti/Cr3C2composite coating
microstructure
wear resistance
high temperature oxidation resistance
