Relationships between scuffing failure load leveldry friction coefficient and alloying elements content of harden surface gears

QI Wen-zheng, GUAN He, GU Xiao-hong
(Zhengzhou Research Institute of Mechanical Engineering Co., Ltd., Zhengzhou 450001, China)

Abstract: In order to solve the problem of our standards of gear scuffing load capacity calculation methods were equivalent to the ISO related standards，the calculation and test data may not apply to our commonly used gear materials and processing technology, six kinds of gear materials which were widely used in China were tested by FZG tester and MM-200 tester.After the experiment of the failure load level of gear scuffing and dry friction coefficient of roller ，content of alloying elements in the materials was analyzed.The test data was provided to do the gear scuffing calculation.The results show that dry friction coefficient can be used to estimate the Hertzian stress on the tooth surface when the gear scuffing in the condition of boundary lubrication. The content of alloy elements has a great influence on the heat conductivity coefficient of materials and scuffing load capacity of harden surface gears. 25Cr2MoV with ionic nitriding has better scuffing load capacity to the other five kinds of carburizing and quenching materials.
Key words: harden surface gears; scuffing failure load level; dry friction coefficient; alloying elements content