| 摘要: |
| 采用火焰热喷涂–中频感应重熔技术在20CrMo抽油光杆基体表面制备NiCrBSi涂层并进行热处理，采用扫描电镜、显微硬度计、X射线应力测试仪、万能试验机和疲劳试验机等仪器，研究了热处理工艺对涂层光杆组织、硬度、表面应力、力学性能和疲劳性能等方面的影响。结果表明，中频感应重熔NiCrBSi涂层的制备和热处理对光杆基材表层组织、硬度和表面应力影响较大，热处理温度对涂层的硬度影响不显著；涂层制备和热处理会显著降低杆体的疲劳性能，重熔处理工艺的抗拉强度最大但塑性指标很差，并在疲劳试验中出现典型脆性断口，高温热处理工艺可以使涂层光杆获得较好的拉伸力学性能；普通20CrMo抽油光杆以磨损、腐蚀和疲劳断裂为主要失效原因，而NiCrBSi涂层/20CrMo光杆疲劳性能的显著降低可能成为其失效的主要原因。 |
| 关键词: 中频感应重熔 NiCrBSi涂层 热处理 拉伸力学性能 疲劳性能 |
| DOI： |
| 分类号: |
| 基金项目:中央高校基本业务费自由探索项目（2010ZY51，2011YXL020）；国际合作重点项目（2010DFR50070） |
|
| Influence of Heat Treatment on Properties of NiCrBSi Coatings on Polished Rods Prepared by Medium Frequency Induction Remelting |
|
TIAN Bin, WANG Cheng–biao, HU Bin, YUE Wen, LIU Jia–jun1,2,3
|
|
1. School of Engineering and Technology, China University of Geosciences, Beijing 100083;2. Shanxi Taigang Stainless Steel Co.,Ltd., Taiyuan 030003;3. Mechanical Engineering Department, Tsinghua University, Beijing 100084
|
| Abstract: |
| NiCrBSi coatings were prepared on the 20CrMo polished rods by flame spraying and medium frequency induction remelting. And then treatment was carried out on the samples. The influence of heat treatment on properties of NiCrBSi coatings on polished rods, including metallographic structures, hardness, surface residual stress, tensile properties and fatigue properties, was studied by SEM, MicroHardness Tester, X Ray Residual Stress Tester, Universal Experimental Machine and Fatigue Testing Machine. The results show that the coating preparation and heat treatment affect the metallographic structures of nearsurface of the substrate obviously. The influence of heat treatment on coating hardness is slight. The coating preparation and heat treatment sharply reduces the fatigue cycle numbers of the 20CrMo polished rods. The remelted rod without other heat treatment show the best tensile strength, the worst plastic strength, and brittle fatigue fracture. Heat treatment of high temperature can get better tensile properties and normal fracture appearance. The wear, corrosion and fatigue fracture are the main failure modes of the 20CrMo polished rods. Worse fatigue properties of NiCrBSi coating may be the main failure reason of the NiCrBSi coating/20CrMo polished rods. |
| Key words: medium frequency induction remelting NiCrBSi coatings heat treatment tensile properties fatigue properties |
