Surface and profile treatment of China's U71Mn heavy rail using abrasive waterjet.

Abrasive waterjet, which is capable of machining all kinds of materials without generating obvious heat and dust, was proposed for treating rail for the first time. With the employment of China's U71Mn heavy rail of 60 kg/m, the fitting method for the cross-section profile of the rail head and the compensation cutting strategy of abrasive waterjet were proposed. The feasibility of rail surface treatment using abrasive waterjet and the influence of jet pressure and traverse speed on the profile deviation and surface roughness were studied. Moreover, both the macro-morphology and micromorphology of the rail surface before and after abrasive waterjet treatment were analyzed using the scanning electron microscope. Results show that abrasive waterjet could effectively remove the surface defects like pits, rust, and microcracks under the experimental conditions. Jet pressure and traverse speed greatly affect the surface roughness and profile deviation. In addition, the profile deviations and the surface roughness of the rail surface treated by abrasive waterjets could satisfyingly meet the acceptance standard (Chinese TJ/GW170-2021). To be more specific, the rail profile and surface roughness after treating can reach 0.337 mm and 2.691 μm, respectively, at jet pressure of 400 MPa and traverse speed of 200 mm/min. [ABSTRACT FROM AUTHOR]