20MnCr5 steel is often used to manufacture the transmission gear.During the process of gear grinding after case-hardening

there usually are grinding burns in the tooth surface

which decreases the surface quality of gear.According to the analysis of the essentiality of grinding burns and the effect on the gear surface

some main factors

including grinding wheel

grinding process

cutting fluid and carbon concentration of hardened case

are illustrated and thus some methods to solve the problem in grinding process are proposed.