Forgings according to the purpose of heat treatment and process location, can be divided into the preparation of heat treatment and final heat treatment of two categories.
1. General rules for determining the position of heat treatment process Forging preparation heat treatment (normalizing, annealing, tempering, etc.) the process is generally arranged after the rough production, before cutting, or rough machining, before finishing.
The final heat treatment (quenching, tempering, chemical heat treatment, etc.) after a high hardness, in addition to grinding, in general, is not suitable for other cutting process, so its process position is generally arranged in the semi-finishing, grinding (finishing) before. In the process of forging production, the heat treatment process will increase or decrease due to the different materials and process.
Therefore, the arrangement of the operation position must be flexibly applied according to the specific circumstances.
2, determine the location of heat treatment process examples Lathe Spindle is an important part of transfer force, it bears alternating load, and the shaft neck requires wear-resisting. Generally selected medium carbon non-alloy steel (such as 45 steel) manufacturing.
The technical conditions of heat treatment for forgings are: Overall quenching and tempering, hardness 220?250HBSF the axle neck and cone hole surface hardening, hardness 50?52HRC.
Spindle Manufacturing route:
Forging-normalizing-cutting (coarse)-quenched and tempered-cutting (semi-fine)-high frequency induction heating surface quenching-low temperature tempering-grinding High-frequency induction heating surface quenching + low-temperature tempering as the final heat treatment, high-frequency induction heating surface quenching is to make the shaft neck and cone hole surface to obtain high hardness, wear resistance and fatigue strength; Low temperature tempering is to eliminate stress, to prevent cracks in grinding, and to maintain the high hardness and wear resistance of forgings.