Carburizing and quenching defects of slender shaft parts can be easily solved by micro high-frequency induction heating power supply

Among various types of textile machines, low carbon steel (such as 20 steel, etc.) slender shaft carburized and quenched parts have a greater variety and quantity, and play an important role in the heat treatment of textile machinery parts. As we all know, after carburizing and quenching, slender shaft workpieces (L/D≥30) will deform greatly, generally about 1-5mm. The workpiece needs to be straightened before grinding. The hardness of the workpiece after quenching is high, and the straightening is difficult and time-consuming. The productivity is low, and the straightening fracture failure is easy to occur. At the same time, uneven hardness and softness often occur after quenching, and the scrap rate of rework is high. After analyzing the reasons, it was found that using a miniature high-frequency induction heating power supply for heat treatment can effectively prevent the occurrence of such defects.

The carburizing process for the slender shaft is (920±10)℃ Tempering, straightening after tempering.

In order to change the defects of the original process, such as large deformation of the workpiece, easy cracking during alignment, and uneven hardness after quenching, an improved process was proposed.

The workpiece is quenched and heat treated using a micro high-frequency induction heating power supply. The quenching temperature is (760℃±5℃). After quenching, the hardened layer is shallow and the infiltration layer structure is lath martensite and fine point-like undissolved carbide, and its deformation is small. , the impact toughness value is greatly improved; the core structure of the workpiece is low carbon martensite, the grains are refined, and the strength and toughness are very good. Therefore, after the slender shaft is induction quenched using the new process, it is less likely to break. Moreover, due to the use of salt water quenching, the surface hardness of the workpiece is very uniform and the performance is excellent.

After adopting the improved technology, the slender shaft fully meets the technical requirements, the surface hardness is very uniform, the deformation of the entire length of the workpiece is about 0.5-1.5mm, and there is no breakage after straightening. After straightening, the deformation drops to 0.05-0.5mm. The workpiece production efficiency is increased by 4-6 times, and the economic benefits are very significant.