【摘要】 本文从摩擦学角度出发通过正交试验对LT(无污染硫氰共渗)工艺的处理参数进行了优化,指出赋予不同基材最佳承载能力和耐磨性的处理参数都明显不同,同种基材获得最佳耐磨性的处理参数则随载荷范围的不同而改变,提出了各处理参数与几种材料共渗层最高抗擦伤载荷之关系的经验公式,并且指出共渗层的承载能力与其结构有关,而与盐浴中所含二价硫离子的多少无对应关系。文章还借助于现代分析手段对共渗层的磨损机理进行了研究,提出了新的看法。更多还原

【Abstract】 The treatment parameters of LT technique were optimized from tribological viewpoint by means of orthogonal test method. Using a regression method and orthogonal polynomials, a group of practical formulae to explicate the regulations of treatment parameters and the highest load-carrying capacity for 40Cr, W18Cr4V and 1Cr18Ni9Ti was obtained and the range of each parameter adopted in the test can be theoretically estimated according to desired targets (OK values). The paper points out that the influence curve of each treatment parameter on the load-carrying capacity is npt a simple linear relation but is a quadratic or cubic relation. The load-carrying capacity of workpieces treated by the LT technique deponds not only on S2- but also on time, temperature and CNO-. The conclusion is distinctly different from the viewpoint which is used to say that load-carrying capacity of workpiece depends only on S2- in salt bath. The test results shown that the treatment parameters to obtain the highest load-carrying capacity and wear resistance is obviously different when the substrate material is varied, the treatment parameters to obtain the best wear resistance for same material is various with the change of test load. Under the condition of boundary lubrication, wear of codiffused layer in the beginning period is more serious because its superficial layer is no sulphur, but when wear scratch gets into rich sulphur field wear will obviously be improved and with the increasing of rich-sulphur layer or distribution range of sulphur penetrated in codiffused layer, the load-carrying and anti-adhesive wear capacity will be much better. In the period of wear, sulphide existed in the holes of wear surface and in immediate surface can be shifted to the two surfaces of the friction pair, so that it is very effective to decrease direct contact between two metals and to increase anti-adhesive wear capacity. In fact, sulphide is basically distributed in all compound layer under some treatment conditions, so it can not constantly have a great role on anti-adhesive wear until the compound layer is worn out.更多还原