Some Factors Influencing the Pitting, Micro-Pitting (Frosted Areas) and Slow Speed Wear of Surface Hardened Gears

Abstract

Surface hardness and hardening depth are the most important influence factors for the load capacity of surface hardened gears. Besides the structure of the hardening pattern, it’s carbon content, amount of retained austenite, residual stress and white layer (nitrided gears) have a considerable influence. Lubricant and material of the mating gear as well as roughness of the tooth flanks have a different influence on pitting, micro-pitting and wear.

Choosing Profile Shift Coefficients for Spur Gears

“…They found, that the minimal positive value of profile shift coefficient makes significant increase of scuffing safety value. Plewe [10] examined the wear of spur gears. He established a method for the linear wear.…”

Determination of the accelerated RCF operating condition of the sun-planet contact of a tractor final drive using a computational method

“…The other potential factors such as surface hardness [20], residual stresses [14], material micro-structures [21], and lubricant additives [20,22,23] may also affect the fatigue crack formation, while not through the direct alteration of the stress distributions. A large number of studies have been focusing on the numerical modeling of the fatigue crack formation.…”

“…The factors that influence the severity of the surface stresses and consequently the fatigue life are diverse, primarily including the operating conditions (surface velocities, sliding direction, normal load, temperature) [1][2][3][4]15], the surface conditions (surface roughness, texture) [2,[16][17][18][19][20], and the lubricant properties (viscosity, non-Newtonian behavior) [9,20]. The other potential factors such as surface hardness [20], residual stresses [14], material micro-structures [21], and lubricant additives [20,22,23] may also affect the fatigue crack formation, while not through the direct alteration of the stress distributions.…”

Investigation of lubricant viscosity and third-particle contribution to contact behavior in dry and lubricated three-body contact conditions

“…These studies show that viscosity is a critical factor in the tribological performance of lubricated interfaces. Simultaneously, it is also one of the causes of tribological failures such as pitting (Winter and Weiss, 1981;Oila and Bull, 2005) and scuffing (Peterson and Winer, 1980;Horng et al, 1995). Recently, new methods have achieved lower friction and wear, such as the manipulation and control of friction through self-organization, manifested in both selective transfer of material and superlubricity.…”