The method and importance of tempering treatment of precision castings of machine tools

The heat treatment of precision castings of machine tools is an important process in mechanical manufacturing. Compared with other machining processes, heat treatment generally does not change the shape and overall chemical composition of the workpiece, but by changing the microstructure inside the workpiece, or changing the cast iron platform and The chemical composition of the surface of the machine tool lost wax casting can give or improve the performance of the workpiece. Its characteristic is to improve the inherent quality of cast iron platform and machine bed castings.

In order to make machine tool precision castings have the required mechanical properties, physical properties and chemical properties, in addition to the reasonable selection of materials and various forming processes, heat treatment processes are indispensable. In addition, aluminum, copper, magnesium, titanium, etc. and their alloys can also change their mechanical, physical and chemical properties through heat treatment to obtain different performance properties. Integral heat treatment is a metal heat treatment process that heats the cast iron flat plate, cast iron bent plate or machine bed castings as a whole, and then cools them at an appropriate speed to change the overall mechanical properties of the cast iron platform, flat plate, cast iron bent plate or machine bed lost wax casting.

The overall heat treatment of machine tool bed castings, machine bed columns, machine tool tables and other castings generally includes four basic processes: annealing, normalizing, quenching and tempering. As a large-scale casting, the machine tool bed casting product must undergo aging treatment to improve its performance and improve the inherent quality of the bed lost wax casting. When the machine bed castings are tempered, the tempering process should be strictly followed, and supporting ribs should be added to the dense or easily deformed parts of the ribs to prevent deformation and fracture caused by the tempering temperature. Special personnel should take care of the tempering furnace thermometer and control the temperature in time to prevent the temperature from being too high or too low, which will have a great impact on the tempering workpiece.