论文部分内容阅读
一、碳势控制原理多数热处理气氛是含CO、CO_2、CH_4、H_2和水蒸汽的混合气体。这些气体的相对含量决定于所使用的气体发生器的形式、操作温度和在处理时添加气体的含量。例如,由天然气与空气经催化作用裂化产生的吸热型发生气的成份如下(按体积%):CO—20 CO_2—0.1～0.5H_3—40 H_2O—0.2—1.2N_2—40 CH_4—0.2—0.8气体渗碳,工业生产中一般是用吸热型气体作载体气,用天然气或丙烷作富化气。一般来说,在原理上是用控制水蒸汽浓度(露点)或CO_2浓度的办法控制碳势。下列平衡反应式,可作为碳势控制原理的一例:2CO=C+CO_2 (1)
First, the carbon potential control principle Most heat treatment atmosphere is a mixed gas containing CO, CO_2, CH_4, H_2 and water vapor. The relative amounts of these gases depend on the type of gas generator used, the operating temperature and the amount of gas added at the time of the treatment. For example, the composition of the endothermic gas generated by the catalytic cracking of natural gas with air is as follows (by volume%): CO-20 CO 2 -0.1 ~ 0.5H_3-40 H_2O-0.2-1.2N_2-40 CH_4-0.2-0.8 Gas carburizing, industrial production is generally used as carrier gas endothermic gas, with natural gas or propane as a rich gas. In general, the carbon potential is controlled by controlling the water vapor concentration (dew point) or CO 2 concentration in principle. The following equilibrium equation can be used as an example of the carbon potential control principle: 2CO = C + CO_2 (1)