等离子熔覆铁基冶金熔覆层的组织与性能

Microstructure and properties of iron-matrixed plasma cladding metallurgical layer

采用等离子熔覆技术,通过对材料及工艺的参数优化,在现有耐磨材料的基础上研发新型铁基耐磨熔覆层材料。对研发的4种新型熔覆层进行性能评价,结果表明,B、C、D试样的冶金结合都比较好,熔覆层从熔合线往上的组织变化比较平缓,为平面晶、枝晶及等轴树枝晶;B试样熔覆层组织中气孔率极小,硬度最高,A试样在组织和硬度性能上都有缺陷;摩擦过程中摩擦因数均呈现4个变化阶段:迅速下降区、小幅上升区、波动区和稳定区,C试样的磨损量最少,磨损形貌最轻微;基底的磨损机制以黏着磨损、磨粒磨损以及疲劳磨损为主,熔覆层材料以磨粒磨损为主。

Abstract： Plasma cladding technology was applied to develop new-type wear-resistant iron-matrixed cladding layer based on current wear-resistant material after optimization of material and technological parameters. And then the properties of developed four kinds of material were appraised. The results showed： sample B, C, D had superior metallurgical bond, their microstructure involved plane crystal, dendritic crystal and equiaxial dendritic crystal varied fiat above fusion line; the mierostructure of cladding layer of sample B was characterized by a little porosity and the highest hardness, while sample A had defect both on microstructure and hardness; the friction coefficient showed there were four variation zones which was rapid decline zone, slight increase zone, fluctuation zone and steady zone in friction process, and sample C was characterized by the minimum wear loss and the slightest wear morphology; the abrasion of the matrix was dominated by adhesive abrasion, abrasive abrasion and fatigue abrasion, while the abrasion of the cladding layer was dominated by abrasive abrasion.