高温下QPQ表面改性层的干滑动摩擦磨损性能研究
本试验以Q345B钢为原材料，通过正交法进行16组QPQ盐浴复合处理试验和高温摩擦磨损试验。并利用OM、显微硬度计、SEM、X射线衍射仪、激光共聚焦扫描显微镜、高温摩擦磨损试验机分别对处理后的渗层显微组织、显微硬度、化学成分、物相、磨痕粗糙度和耐磨性进行研究，相成分等进行分析。结果表明Q345B钢在QPQ处理后表面由外到内可形成明显的白亮层和扩散层，且渗层厚度随着氮化时间的延长增大；样品表面有Fe2-3 N和Fe3O4组成；Q345B钢的最佳QPQ工艺参数为560℃渗氮150min，390℃氧化20min。QPQ能显著增加Q345B钢的耐磨性，调质试样和圆钢的磨损量分别是QPQ处理之后的7倍和9倍。在250℃下摩擦磨损时以磨砺磨损和黏着磨损并存，氮化温度较高时，磨痕表面出现的塑形流变越明显，黏着磨损越严重，并存在氧化磨损。
毕业论文关键词：QPQ技术；正交试验；高温摩擦磨损
Abstract QPQ technology is a kind of can also greatly improve the wear resistance of the metal surface and the corrosion resistance of a metal surface modification technology and strengthening, in fact, quality is low temperature salt bath nitriding and oxidizing salt bath or low temperature salt bath carbon and nitrogen co permeation of comprehensive application of the molten salt oxidation +。QPQ in mechanical manufacturing industry, automotive and other fields, in order to improve the wear resistance of the products, resistance to fatigue strength and corrosion resistance。
The blade cutting copper finned tube loss, short cycle, in the context of this test by QPQ to improve its wear resistance, prolong the service life of the blade, and can be used in a high temperature。 In this experiment, Q345B steel as the raw material, test compound treatment group 16 QPQ salt bath and high temperature friction and wear through the orthogonal test method。 And the use of OM, micro hardness tester, SEM, X ray diffraction, laser confocal scanning microscopy, high temperature friction and wear tester respectively on microstructure, microhardness after the infiltration process, chemical composition, phase, grinding surface roughness and wear resistance were studied, and complementary classification analysis Q345B steel。 The results showed that after QPQ treatment the surface from outside to inside were formed in the white layer and diffusion layer, and the thickness of the layer with the increase of nitriding time; Fe2-3 N and Fe3O4 sample surface composition; the optimum QPQ process of Q345B steel Parameters for 560℃ nitriding 150min, 390℃oxidation 20min。QPQ can significantly reduce the friction coefficient of Q345B and reduce the amount of wear。 At 250℃ for the friction and wear to sharpen the wear and adhesive wear coexist, and there oxidation wear。
Keywords:QPQ; Orthogonal test; High temperature friction and wea;
目录
第1章 绪论 - 1 -
1。1 问题的提出及研究意义 - 1 -
1。2 QPQ盐浴复合技术简介 - 1 -
1。2。1 QPQ工艺过程和各工序作用 - 1 -
1。2。2 QPQ盐浴复合处理技术特点 - 3 -
1。3 QPQ熔盐组成与原理 - 5 -
1。3。1 QPQ盐浴的发展现状 - 5 -
1。3。2 基盐的调整与开发 - 6 -
1。4 QPQ渗层形貌及特征 - 6 -
1。4。1 渗层的形成 - 6 -
1。4。2 渗层形成的影响因素 - 9 -