Important development trend of vacuum atmosphere furnace

In the development trend of less non-oxidizing heat treatment technology, the development of vacuum atmosphere furnace is rapid. In the current small variety and mass production, especially the bright quenching, annealing, carburizing quenching, carbonitriding quenching, and gas nitrocarburizing of carbon steel and general alloy structural steel parts are still mainly based on the application of controllable atmosphere means. Therefore, atmosphere furnace heat treatment is still the main component of advanced heat treatment technology.

The gas source for the preparation atmosphere. In the process of mastering and promoting controllable atmosphere, our country has come a long way in solving the problem of atmosphere. The early endothermic atmosphere generators mainly used liquefied gas, that is, propane or butane with higher purity. In recent years, it has been confirmed that my country’s abundant natural gas resources have created good conditions for the preparation of endothermic atmospheres with methane. The use of a direct-generation atmosphere without a raw furnace is also a way that cannot be ignored.

Vacuum atmosphere furnace heating equipment. The sealed multi-purpose furnace and the multi-purpose furnace production line have a high degree of automation, large production flexibility and strong applicability, so they are widely used.

The small distortion of the workpiece is a very important advantage of the vacuum atmosphere furnace. According to domestic and foreign experience, the distortion of the atmosphere furnace is only one third of that of the salt bath heating and quenching. It is of great significance to study the vacuum heating methods of various materials and parts with different complexity levels and the distortion laws under various cooling conditions, and to simulate them with a computer, which is of great significance for the promotion of vacuum atmosphere furnace technology. The uniformity of air flow during vacuum heating, normal pressure or high pressure air quenching has a great influence on the quenching effect and quality dispersion of parts. The use of computer simulation methods to study the air circulation law in the furnace is of great significance for improving the structural changes of the furnace. Vacuum carburizing is a possible way to achieve high temperature carburizing.

However, heating for a long time at high temperature will make the austenite grain size of most steels grow very large. For specific steel high-temperature carburization, the influence of reheating and quenching on the properties of materials and workpieces will be studied, and the optimization of vacuum infiltration will be studied. Carbon, cooling, heating and quenching processes and equipment are necessary. In recent years, there has been international research and development of combustion-type vacuum furnaces using gas fuels. It is too difficult to use gas fuel to heat in a vacuum atmosphere furnace. Although there is a saying of energy saving, it is not necessarily an important development direction.