FZG Gear Efficiency and Pin-on-Disc Frictional Study of Sintered and Wrought Steel Gear Materials

Abstract

Load-dependent power loss is a major contributor to power loss in gear transmission systems. In this study, pin-on-disc frictional and FZG efficiency experiments were conducted with powder metallurgy (Distaloy AQ ? 0.2 %C) and wrought material (16MnCr5) combinations. The gear mesh torque loss from gear efficiency tests and the friction coefficient from the pin-on-disc tests were then compared. The trend for both test series was the same. The combination of 16MnCr5 in contact with Distaloy AQ ? 0.2 %C shows the lowest coefficient of friction and gear mesh torque loss, followed by the combination of Distaloy AQ ? 0.2 %C in contact with itself and finally the combination of 16MnCr5 in contact with itself.

A study of the efficiency of spur gears made of powder metallurgy materials – ground versus super-finished surfaces

“…This is mainly because fewer surface peaks are in contact for the superfinished gears. Note that the mechanism of the difference in efficiency between RS-RS and AQ-AQ ground gear combinations was studied in detail in [14], and will not be discussed here.…”

“…8 shows an optical micrograph of a cut section of the AQ material gear tooth showing porosities on or near the surface. Li et al [14] showed that the porosities of AQ can lower the friction coefficient of pin-on-disc experiment and gear mesh torque loss of FZG gear efficiency experiment. Fig.…”

“…Li et al [13] used pin-on-disc experiments to show that regular steel (16MnCr5) disks on PM material pins, and PM material disks on PM material pins, had lower friction coefficients than regular steel disks on regular steel pins. On the basis of these results, Li et al [14] investigated the gear mesh torque loss of regular steel gears and PM material gears. They found that running a standard material gear against a PM gear can improve efficiency.…”

“…The Young's modulus and Poisson's ratio [13,14] of powder metallurgic materials are lower than those of standard gear steel, and this influences the bending stiffness. It is thus necessary to check whether these differences will alter the contact stress, sliding speeds, and film thickness at the contact point and so affect gearbox efficiency.…”

“…Li et al [14] investigated the gear mesh torque loss of regular steel and PM material ground gears but the efficiency of superfinished PM gear are unknown. Using efficiency data for ground [11] and super-finished [12] regular steel gears as a base for further research, here we undertook additional research using the same test setup for super-finished gears made of PM material.…”