Experimental investigation and prediction method of fretting wear in rack-plane spline couplings

Abstract

To investigate the fretting wear of involute spline couplings in aerospace, rack-plane spline couplings rather than the conventional involute spline couplings in aerospace were used to conduct tribological experiments, and it was assumed that the rack-plane spline couplings exhibit consistent contact stress with the real involute spline couplings in aerospace. The relationships among the static friction coefficient, dynamic friction coefficient, and fretting friction coefficient were established via tribological experiments, as well as the fretting-wear mechanism of the rack-plane spline couplings was examined. A fretting-wear estimation model based on the fretting-wear mechanism was developed. By applying the modified Archard equation and Arbitrary Lagrangian–Eulerian adaptive, mesh smoothing algorithm of Abacus was used. According to our experimental results, the fretting wear of the rack-plane spline couplings consisted primarily of abrasive wear, oxidative wear, and adhesive wear. For both, lubrication and non-lubrication settings, the fretting friction coefficient of 18CrNi4A steel (0.27) fluctuated between 0.12 (dynamic friction coefficient) and 0.35 (static friction coefficient). The fretting-wear results estimated via numerical prediction were consistent with the experimental results. When sm (vibration amplitude) was 20, 35, and 50 µm, the most difference in the fretting wear between the experimental results and numerical estimation was 0.001, 0.0007, and 0.001 mm, respectively. Therefore, the proposed model provides a method for accurate estimation of the fretting-wear. Additionally, the model contributes to the precise design of involute spline couplings in aerospace.

Friction Evolution of Graphite Bearing Impregnated with Polymer Subjected to Vibration Fretting at High Temperature

“…These materials exhibit noteworthy tribological properties. Their effectiveness in friction and wear is showcased especially under ambient air conditions at moderate temperatures [1,3]. However, the low friction coefficient of graphite (µ = 0.1) is contingent on several factors, such as the applied dynamic load, temperature, gaseous environment, surface roughness and contact geometry.…”

“…During contact, sites are formed in notch positions on monoatomic height steps. These highly energetic sites, separated by low-energy surfaces, create adhesive bonds during contact, leading to severe friction and wear [3,[8][9][10][11][12][13][14][15][16][17][18][19][20][21]. In the presence of water vapor, these sites become saturated, reducing their reactivity.…”

Fretting tribological performance of DLC, TiAlN and DLC/TiAlN coatings deposited on carburized 18CrNi4A steel

“…18CrNi4A steel has excellent tensile strength, high hardness and wear resistance, and other comprehensive mechanical properties after carburizing heat treatment, and is widely used for heavy-duty transmission components such as gears, spline couplings, drive shafts, and bearing rings of aero-engines and helicopter reducers [1][2][3][4][5]. Reports indicate that failures caused by spline couplings account for approximately 10% to 20% of all failures in helicopter transmission systems, and that over 90% of failed spline couplings are the result of wear [3].…”