钒在高锰钢中扩散的试验研究

Study on the Vanadium Diffusion of High-manganese Steel

在1 500℃下,采用毛细管-熔池法进行钒在高锰钢中的扩散试验,用EPMA分析和测定钒在毛细管轴向的浓度分布,采用一维稳源半无限长棒扩散模型,由Fick扩散第二定律求解钒原子的扩散系数。用光学显微镜和XRD研究材料的显微组织和物相组成,显微组织结构和微区成分分析表明,在材料的奥氏体基体上分布着细小颗粒状和团块状碳化物增强相,并以毛细管靠近扩散源一端为起点,钒元素浓度及碳化物的数量沿毛细管轴向呈梯度下降(减少)分布。用HX-1000TM显微硬度计检测试样的硬度,结果表明材料硬度沿试样轴向也呈下降趋势,梯度分布特性明显。

Based on diffusion test of Vanadium in high-manganese steel using capillary-molten pool method under the temperature of 1 500 ℃,the EPMA is used to analyze and determine the concentration distribution of Vanadium in the capillary axial direction.The one dimensional stability source and a half of infinite long great diffusion model is adopted to solve the diffusion coefficient of Vanadium atoms by the Fick＇s second law of diffusion.Study on the microstructure of materials and physical phase composition by optical microscope and XRD shows that there are many tiny granule and crumb carbide enhance phase on the austenite matrix in materials.Using the side（near the diffusion source） of the capillary as the starting point,the Vanadium concentration and the amount of the carbide gradually descent along the axial direction of the capillary.Using HX-1000TM microhardness tester to test the hardness of the sample,the result reflects that the hardness of the material decrease along the axial direction of the capillary,and the gradient distribution character is apparently.