不同扫描速度下电子束重熔处理253MA不锈钢的研究

Research on 253MA stainless steel treated with electron beam remelting at different scanning speeds

为提高253MA钢的表面性能,对其进行电子束表面重熔处理,并使用扫描电镜(SEM)、显微硬度仪及摩擦磨损仪对其微观组织、显微硬度和耐磨性能进行表征。结果表明:改性后不锈钢的表面形貌得到有效改善,其表面粗糙度下降。微观组织晶粒得到细化,亚晶和位错密度增加。当扫描速度增加时,改性试样的表面硬度和耐磨性随之提升。当扫描速度为600 mm/min时,253MA钢的表面硬度达到最大值243.3 HV,其耐磨性最好,是原始试样的1.7倍。

To improve the surface properties of 253MA steel,electron beam surface remelting treatment was performed,and its microstructure,microhardness,and wear resistance were characterized using scanning electron microscopy(SEM),microhardness tester,and friction and wear tester.The results showed that the surface morphology of modified stainless steel was effectively improved,and its surface roughness decreased.The microstructure grains are refined,and the density of subgrains and dislocations are increased.As the scanning speed increases,the modified sample’s surface hardness and wear resistance also increase.When the scanning speed is 600 mm/min,the surface hardness of 253MA steel reaches the maximum value of 243.3 HV,and its wear resistance is the best,1.7 times that of the original sample.