α状态离子渗氮层中的氮化物形貌和元素分布

利用离子探针,电子探针等现代测试手段,研究了40Cr,35CrMo和38CrMoAlA钢分别经离子氮化和气体氮化处理后的试样离子氮化层中的氮化物形貌和元素氮、碳、铬、钼、铝的分布,为深入研究α状态渗氮层组织结构与磨损机理,提供了一定的理论依据;同时也为新的氮化钢种的研制和氮化工艺的选择与控制提供了重要信息。

Morphology of Nitrides and Alloying Ingredient Distrubution in a -state Ionic Nitriding Case

Observes the morphology of nitrides and analyzes the alloying ingredient distribution of such elements as N, C, Cr, Mo and Al in ionic nitrided case of 38CrMoAlA and 40Cr steels in order to explore the structure of ionic nitrided case in relation with their properties. With the presence of Al, the nitrides in 38CrMoAlA are grown as thin plates, while those in 40Cr exhibit themselves as particles. The N distribution in different specimens subjected to nine kinds of nitriding process are respectively detected and as a result the more the number of penetrating elements, the higher the N content in surface. Carbon would not escape from the nitrided case, but its content is just higher than that in matrix. A carbon-rich surface is shown after ionic nitriding by the increase in surface layer dislocation density. Alloying ingredients as Cr, Mo and Al become higher in surface layer after ionic and gas nitridings since the nitrides by Cr, Mo and Al are obviously more stable than those by Fe.