Dalian surface heat treatment can significantly improve the fatigue strength of workpieces

Dalian surface heat treatment can significantly improve the fatigue strength of workpieces:

Dalian surface heat treatment can significantly improve the fatigue strength of workpieces. For example, the automotive half shaft made of 40MnB steel was originally quenched and tempered as a whole, but was changed to quenched and tempered+surface heat treatment, which increased its lifespan by nearly 20 times. In addition, surface heat treatment reduced the sensitivity of the parts to notches. The size of the outer panel mold is generally larger,

If a patchwork structure is used, there will be tensile damage at the joints, so most integral structures are used, and the materials are generally cast iron materials such as ductile iron. After flame quenching, the hardness of the forming and feeding parts can reach around 50-55HRC. The surface treatment of the outer plate mold for the overall structure of Dalian Metal Surface Treatment mostly adopts the hard chromium plating process,

However, its surface hardening effect is limited, with a surface hardness of about 1000HV. In addition, the hard chromium plated coating is mechanically combined with the mold base material, making it easy to peel off under high forming pressure. Once the coating peels off, its tensile resistance will also be lost. When the surface hardening layer wears out, burrs will appear again.

This technology can be used for molds with low requirements. The wear resistance and fatigue wear resistance of surface heat treatment under dry friction sliding wear conditions are higher than those of ordinary heat treated parts. This is due to the combined results of small martensite grains, high carbide dispersion, and high pressure stress on the surface in its structure.

It has excellent wear resistance, self-lubricating, anti bite, high-temperature oxidation resistance, and corrosion resistance, which can improve the service life of molds by several times or even 10 times, and has received high praise in the mold industry.