1. Effect of temperature on gear deformation
There is no doubt that with the increase of heating temperature and quenching temperature, the heat treatment deformation of parts will increase. Therefore, the quenching temperature of general parts should be as low as possible on the premise of ensuring hardness and metallographic structure. For gear parts with high deformation requirements and deep carburizing layer, carbonitriding or reducing carburizing temperature can be used to reduce quenching deformation.
2. Influence of quenching medium and quenching cooling specification on gear deformation
The quality and service temperature of quenching medium have a great influence on the deformation. The quality of quenching medium affects the quenching stability of parts. Reasonable medium service temperature can reduce thermal stress and reduce deformation. Medium stirring mode and speed also affect the deformation of parts. On the premise of meeting the quenching performance of parts, mild stirring mode, low stirring speed and high oil temperature are reasonable measures to reduce the deformation of parts.
Therefore, the type of quenching oil, oil temperature and mixing mode used for specific parts are generally fixed after debugging, so as to stabilize the deformation of parts.
3. Influence of carburizing and quenching equipment
As we all know, different levels of heat treatment carburizing equipment have different control accuracy, such as temperature control accuracy, carbon potential control accuracy, etc. Therefore, the heating speed, heating uniformity, atmosphere uniformity and process repeatability of parts are different due to different levels and states of equipment, and the deformation of parts will certainly have relatively different results.
In a word, the obvious deformation of gear is produced in the heat treatment process, but the size and law of deformation mainly depend on the material, shape and the quality of the whole process. Reasonable design, excellent material, precise forging, standardized pre heat treatment, effective cold and hot processing cooperation, and scientific heat treatment control are all indispensable and important factors to reduce and stabilize gear carburizing and quenching deformation.