In the brazing furnace parts carburized control method

In the brazing furnace parts carburized control method

Parts carburizing in the brazing furnace control method, when the carbon carrier of hydrocarbon gas into the vacuum furnace, this method is available to control. Respectively under vacuum and negative pressure carburizing is known to all. Available hydrocarbon gas as gas carburizing agent, and the most common is methane. In certain furnace gas composition is known, is CH 'and N:, for example, or CH' + CO N: 10, a H:. Using these methods, because between the gas and carbon amount carburizing steel need not form a chemical equilibrium, so the oversupply in the gas carbon measures must be taken, for example through supply 0 h4. The necessary of excessive hydrocarbon gas supply has a weakness, is in the reaction process has yet to reach the free carbon occurs on the surface of the steel, such as the reaction of methane CH '= C + useful: black carbon is produced by this kind of free carbon and, with the concentration increased, the carbon black into carbon black cloud and visible.
It has two drawbacks: first, obstruct carburizing; Second, the pollution is carburizing and furnace. In addition and cause the danger of short circuit in the electric heating furnace. In order to reduce the carbon black, already use fixed pulse or how many according to adjust the way of pulse, quantity and time on the amount of hydrocarbon gas supply vacuum furnace control. But this method cannot obtain the effective results, and for the formation of infiltration layer depth and some inadequacies in the border carbon content, in order to get better comprehensive effect related to the carbon black form, the need for most different carburized parts determined by pulse test procedures. Therefore, only do a lot of testing under different conditions.