微动磨损诱发车轴热喷涂层表层显微硬化行为特征研究

Study on Working Hardening Behavior of the Thermally Sprayed Coating of the Axles under Fretting

研究了微动磨损诱发层状铁素体与奥氏体复相组织热喷涂层表层显微硬化行为及磨损表面形貌特征。带状挤出物的出现是涂层在微动磨损条件下塑性变形的表面特征形貌，多系滑移的滑移带交叉重迭诱发涂层内部产生微裂纹。微动磨损的车轴涂层表层及无涂层车轴表层的显微硬度分布测量结果对比分析表明，微动磨损塑性变形导致涂层表层显著加工硬化。

The working hardening behavior of the thermal sprayed coating of the axles under fretting has been studied. Occurrence of the bands intrusions structure is a characteristic fretted surface morphology of the coating composed of the dual phases ferrite austenite. The intersected slip bands could be a collection of the microcracking source of the fretted coating. The measured vickers microhardness indicates a stronger working hardening of the fretted coating surface layer, playing an important role in preventing the axles from further fretting damage.