2Cr13不锈钢表面电火花强化及磨损和冲蚀行为研究

采用电火花表面沉积(ESD)技术,选用YG-8硬质合金和石墨两种电极,对2Cr13不锈钢进行表面强化处理。研究了强化层深度的影响因素,采用辉光放电谱仪(GDS)测试强化层元素分布,用X射线衍射仪(XRD)分析组织结构,用球盘磨损试验机评价耐磨性能,用喷砂型冲蚀装置评价冲蚀性能。结果表明:强化层与基体为冶金结合,其深度随电源电压增加而增大,Ar气保护能有效地降低强化层中N、O含量。石墨电极强化层存在大量的Fe3C、奥氏体和少量石墨;硬质合金电极强化层存在大量的W2C、Co6W6C和WC1-x。经YG-8和C电极强化后,2Cr13不锈钢表面的硬度大幅度提高,摩擦系数明显降低,粘着磨损得到有效的控制,耐磨性能得到显著的改善。在10°小冲蚀角条件下,强化层明显提高了基体的抗石英砂冲蚀性能,而90°垂直冲蚀时,强化层的抗冲蚀性能却不及基体,原因是强化层韧性不及基材。

Study of Electrospark Strengthening and Erosion Behavior of 2Cr13 Stainless Steel Surface

The 2Cr13 stainless steel surface is strengthened with the two types of electrode of YG-8 cemented alloy and graphite using the electrospark deposition(ESD) technique.The distribution of chemical elements in a strengthening layer is tested with a glow discharge spectrograph(GDS),components are analyzed with X-ray diffractometer(XRD);its wear-resistance is evaluated by the ball-on-disk wear tester;its erosion behavior is appraised by the solid particle impingement unit.The results show that the strengthening layer and the 2Cr13 matrix have alloying adhesion.The strengthening layer′s thickness increases with the increase of input voltage.Argon protection can remarkably reduce its thickness and the N2 and O2 content in the strengthening layer.The strengthening layer of graphite electrode contains huge quantities of Fe3C and austenite and a little graphite.The strengthening layer of cemented alloy electrode contains much W2C,Co6 W6C and WC1-x.After the electrode strengthening,the hardness of 2Cr13 stainless steel surface increases greatly;its friction coefficient decreases;its adhesion wear is effectively controlled, and its wear-resistance improves.At the low erosive angle of 10°,the strengthening layer enhances the quartz sand particle erosion resistance of the 2Cr13 matrix,while at the erosive angle of 90° the erosion resistance of the strengthening layer is weaker than that of the 2Cr13 matrix due to its lower ductility.