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离子渗碳具有渗速高、表面质量好、渗层均匀、耗能少、无公害、便于自动控制等一系列优点,七十年代以来,越来越引起人们的重视。离子渗碳有两种不同工艺。一种是在原来离子氮化的基础上,提高处理温度和通入渗碳介质,是一种碳氮共渗工艺。例如在520℃以上通入NH_3的同时,通入适量的甲烷或丙烷,也有同时通入第三种元素(如硫)的三元共渗。另一种工艺是在真空渗碳的基础上发展的,在真空渗碳设备中加上辉光放电部件(即阴阳极)。这两种工艺都必须在真空中进行,前者和离子渗氮相似,后者则在离子轰击的同时还设有外热源。显然,前者设备简单,在原有的离子渗氮设备上稍加改装即可;后者则渗速更快,渗层深而均匀。当前在国内外,这两类工艺均有发展。国内如江西齿轮箱厂齿轮的离子碳氮共渗,华南工学院高速钢工具的离子硫碳氮三元共渗。美国金属零件碳氮共渗法也就是离子碳氮共渗法,已申请专利。以上均属于无外热源的低温碳氮共渗工艺。离子渗碳更主要的发展是高温渗碳。苏联用含水丙酮和含水酒精混合蒸汽介质,在1300℃进行了高温离子渗碳的试验,还有在丙烷介质中进行离子渗碳的试验,等把
Ion carburizing has a series of advantages such as high permeation rate, good surface quality, uniform permeation layer, less energy consumption, pollution-free, and convenient automatic control. Since 1970’s, more and more attention has been paid. There are two different ion-carburizing processes. One is the original ion nitriding on the basis of improving the processing temperature and access to the carburizing medium, is a carbonitriding process. For example, at the above 520 ° C into the NH3 at the same time, access to the right amount of methane or propane, but also through the third element (such as sulfur) ternary permeability. Another process is developed on the basis of vacuum carburizing with glow discharge components (ie, cathodes and anodes) in a vacuum carburizing facility. Both processes must be carried out in a vacuum, the former is similar to ion nitriding, while the latter is ion bombarded with an external heat source. Obviously, the former is simple in equipment, and can be modified slightly in the original ion nitriding equipment. The latter is faster in infiltration and deep and uniform in the permeation layer. Currently at home and abroad, these two types of processes have developed. China, such as gear box factory gear ion carbonitriding, South China Institute of High Speed Steel tool ion sulfur carbon and nitrogen ternary infiltration. US metal parts carbonitriding method is the ion carbonitriding method, has applied for a patent. All of the above belong to the low-temperature carbonitriding process without external heat source. The main development of ion-carburizing is carburizing at high temperature. The Soviet Union mixed aqueous steam with aqueous acetone and aqueous ethanol, high-temperature ion carburization at 1300 ° C, and ion-carburizing in propane media