Heating furnace and quenching crack
Heat treatment is a general term for all kinds of mechanical, physical and chemical processes used to modify the structure and properties of ferrous and non-ferrous metals, alloys and their products. They are the basis for improving the performance of machine parts. The heating furnace plays an important role in the heat treatment process. Its role is to make the heat of the heat treatment into the heat of the workpiece, and to create the required heat treatment temperature field.
Quenching is a heating process in which the solution temperature of the metal is heated at a high temperature and cooled rapidly, so that the working part can obtain a certain mechanical properties, such as strength and hardness. During the quenching process, quenching cracks are a kind of defects formed by the interaction of heat and deformation. The impact force between quenching crack and workpiece in the course of work is one of the leading factors to shorten the service life of the workpiece.
The main reasons for the formation of quenching crack are as follows: unsuitable heat treatment temperature, uneven heating of heating furnace, too fast or too slow tempering rate, poor surface hardening of parts, etc., which can be caused by materials, process or other external conditions.
The main measures to eliminate the quenching crack are as follows: optimize the heating process of the heating furnace, including the uniformity of temperature, the temperature of the quenching crack area, the heating rate, the cooling rate and the method used to measure the temperature during the process.Optimize the structure of the processed components, such as reducing the wall thickness, increasing the bending radius and chamfering the edges and corners of the parts. Review and optimize the quenching process parameters such as quenching rate and tempering process parameters such as tempering rate. Change the quenching medium or selection of organic quenching medium and add appropriate modifiers.
It is very important to optimize the heating and heat treatment process of the heating furnace to prevent the formation of quenching cracks. On the basis of selecting the correct heat treatment furnace, the correct treatment parameters should be determined according to the technical requirements of the treated parts, and the service life of the parts can be greatly improved.
