heat treatment for NACE requirement

Metal heat treatment is one of the important processes in mechanical manufacturing. Compared with other processing processes, heat treatment generally does not change the shape and overall chemical composition of the workpiece, but endows or improves the working performance of the workpiece by changing the microstructure inside the workpiece or changing the chemical composition of the workpiece surface. Its characteristic is to improve the internal quality of the workpiece, which is generally not visible to the naked eye.