WC/Cu基仿生非光滑耐磨复合涂层的研究

Study on WC/Cu Based Bionic, Non-smoothed, and Composite Coating

磨粒磨损是矿山、工程和农业机械失效的主要原因 ,采用仿生非光滑表面可提高耐磨粒磨损性能。本文采用高频钎焊方法在 4 5号钢表面制备了 WC/Cu非光滑耐磨复合涂层 ,测试了复合涂层孔隙度 ,研究了 WC质量分数、磨粒尺寸、载荷等对其耐磨性的影响 ,分析了非光滑涂层的磨损机理。结果表明 ,在钎剂为 WC质量 4 %时复合涂层孔隙度低 ,复合涂层与 4 5号钢基体为良好的冶金结合 ,界面区组织致密。磨粒磨损时 ,WC颗粒在涂层表面凸起 ,形成非光滑表面可阻碍磨粒对基体的犁削并使部分磨粒由滑动变为滚动是仿生非光滑复合涂层具有高耐磨粒磨损性能的主要原因。当 WC质量分数在 5 0 %时 ,非光滑涂层耐磨性最好 ,其耐磨性随载荷或磨粒尺寸增大而下降。

Abrasive wear is the main cause for losing efficacy of mine and agricultural machineries. However, a bionic and non-smoothed coating can improve its abrasive resistance. In this paper, a high frequency brazing was applied to prepare a bionic, non-smoothed, and composite coating of WC/Cu on surface of 45# steel. The porosity of this coating was tested and the influence of WC contents, the sizes of the abrasive particles and the load on the abrasive resistance were investigated. The experimental results suggested that when the quantity of the brazing flux was 4% of WC mass, the porosity of the coating would become lower and the interface between composite coating and the steel base would be bonded well. During abrasion, WC particles will protrude from the coating to form non-smoothed surface, which can protect the base metal from ploughing and change the motion of partial abrasive particles from sliding to rolling, which is the main reason for high abrasive resistance of a bionic and non-smoothed composite coating. When the content of WC particles is about 50%, the wear resistance of composite coating comes up to its peak. And then it will deteriorate with the increase of loads or abrasive particles.