Improvement measures of steel ball preventing cracking technology

- Feb 25, 2021-

(1) Forging. Increase the forging ratio and strictly control the forging process to prevent the heart from becoming coarse after forging.

(2) Lowering the quenching water temperature of bearing steel balls and increasing the water outlet temperature can significantly reduce and ease the quenching stress of the workpiece.

(3) Add spheroidizing annealing before quenching to refine the structure so that the workpiece becomes fine needle-like (flake-like.) martensite after quenching to prevent coarse structure after quenching.

(4) Tempering in time after quenching to eliminate quenching stress, stabilize the structure, and further remove the hidden danger of cracking of the workpiece.

After adopting the above process improvement, the failure phenomenon of FAG bearing steel ball quenching cracking is eliminated, the quality of the workpiece after heat treatment is excellent, and the production runs well.