Increase in Wear Resistance of Traction Wheel via Chromizing: A Study Combining Experiments and Simulations

Abstract

The wear failure of traction wheels in orchard transport severely restricts the stability of orchard conveyors and impedes the mechanization of orchard work. In this study, the thermal-diffusion chromizing method was employed to increase the hardness of a traction wheel for the enhancement of wear resistance. The results show that a uniform and dense chrome coating with a thickness of 16 μm was formed on the surface. The coating was revealed to have a hardness of 1752.7 HV and benefited from the formation of Cr-C compounds. A friction test and a wear simulation test under both dry-friction and lubrication conditions were conducted to assess the enhanced wear resistance based on the friction coefficient and wear loss. The friction coefficient of QT400 and that of the chrome coating were 0.37 and 0.36, respectively, under dry conditions. Additionally, the friction coefficient of QT400 decreased to 0.12, while that of the chrome coating remained at 0.35, under lubrication conditions. In the wear simulation test, the wear loss of the chromed traction wheel was about 1/28 of that of the QT400 traction wheel under dry-friction conditions. In addition, the wear loss of the chromed traction wheel was about 1/24 of that of the QT400 traction wheel under lubrication conditions. Moreover, the wear mechanism was analyzed with a microstructure study and finite element analysis (FEA). The synergetic effect between fatigue wear and abrasive wear was likely responsible for the wear failure of the traction wheel. The method proposed in this study may be a promising way to enhance the wear resistance of QT400 traction wheels through the application of a chrome coating without sacrificing the loading capacity, and this work contributes to the understanding of the wear failure mechanism of traction wheels.

Stressed State of Chrome Parts During Diamond Burnishing

“…Chromium coatings are widely used both during the manufacture of new machine parts and during the restoration of worn surfaces of a wide range of parts of piston and plunger pumps, compressors, inter-nal combustion engines, hydraulic and pneumatic cylinders and parts of various machines, etc. [42][43][44].…”

Improved Wear Resistance of Nitro-Chromized Carbon Steel Using an Additional Carburizing

“…Chromium-containing compounds attract widespread attention [1][2][3] in the field of surface modification due to their good thermal stability [1,4], high hardness [1,[5][6][7][8][9], and excellent antioxidant properties [9][10][11]. The surface modification layer composed of chromium-containing compounds always exhibits good wear [4,[12][13][14] and corrosion resistance [5,6,[8][9][10][11]15], thereby prolonging the service life of components in aircraft, automobiles, and ships [16][17][18][19].…”

“…The conventional direct chromizing [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] operates at high temperatures above 900 • C and results in a chromium-containing compound layer mainly composed of chromium carbides, i.e., Cr 7 C 3 , Cr 23 C 6 . Usually, the conventional chromizing layer has a high hardness value in the range of 1200-1800 HV [1,[5][6][7][8][9] and good wear resistance [4,[12][13][14].…”