热喷涂铁基非晶涂层喷涂工艺及耐磨性能的试验研究

采用超音速火焰喷涂技术在 Q 235 钢基体上制备致密的铁基非晶涂层，对非晶涂层的喷涂工艺和涂层的耐 磨性能进行了研究。采用正交实验方法研究喷涂中煤油量、氧气量、送粉率对涂层性能的影响规律并对比分析涂 层孔隙率、硬度和结合强度。采用扫描电子显微镜表征粉末及涂层的结构形貌及摩擦表面形貌，通过 X 射线衍 射仪对涂层的物相和非晶含量进行分析，采用摩擦试验机分析对比涂层与钢基体的耐磨损性能并讨论了失效类型。 实验结果表明在最佳工艺参数下涂层孔隙率、洛氏硬度和结合强度分别为 0.14%、68.1 HRC、70.7 MPa，无明显 裂纹和缺陷。和 Q 235 钢对比，涂层的摩擦系数更为稳定，磨损量更小，涂层磨损机制为疲劳磨损和粘着磨损并 伴随轻微脆性剥落。

Experimental Study on Spraying Process and Wear Properties of Thermal Sprayed Iron-based Amorphous Coating

The dense Fe-based amorphous coating was prepared on Q 235 steel substrate by high velocity oxygen fuel (HVOF) spraying technology. The spraying process and wear resistance of the amorphous coating were studied. The orthogonal experiment was used to study the influence law of coal oil quantity, oxygen quantity, and powder feeding rate on the coating performance, and porosity, hardness, and bonding strength of the coating were compared and analyzed. The powder and coating morphology and friction surface morphology were observed by SEM. The phase constitution and amorphous content were analyzed by XRD. The wear resistance of the coating and substrate was compared and analyzed by friction test machine, as well the failure types of the coating were discussed. The experimental results showed that the porosity, hardness, and bonding strength were 0.14%, 68.1 HRC, and 70.7 MPa respectively under the optimum process parameters, no obvious cracks and defects have been observed. The friction coefficient of the coating was more stable and wear amount was less than Q 235 substrate. The wear mechanism of the coating was fatigue wear and adhesive wear, accompanied by slight brittle spalling.