Machined parts machining process heat treatment, generally can be divided into two kinds of preparatory heat treatment and final heat treatment.
Preliminary heat treatment: its purpose is to improve the mechanical properties, eliminate internal stress, in order to prepare for the final heat treatment, generally including annealing, normalizing, tempering and aging treatment and other such processes. The preparatory heat treatment is usually carried out after rough machining.
Final heat treatment: its purpose is to improve the hardness and wear resistance of the parts, including quenching, carburizing, nitriding and other processes, generally after the semi-finishing process, before the finishing process.
Content two: the precision of machining
The accuracy of machining is mainly reflected in the following aspects: dimensional accuracy, geometric shape accuracy and mutual position accuracy, where geometric shape accuracy includes roundness, straightness and flatness, etc., and mutual position accuracy includes parallelism, perpendicularity and coaxiality, etc.
