Wear study of additively manufactured repair material for R260 grade rails

Abstract

[EN] Additive Manufacturing (AM) has been considered as a promising method for repairing rails and extending their service life. In this work, the wear rates of twin-disc specimens produced through laser additive manufacturing against ER7 material are studied applying creepages from 0.4 % to 2.6 %. The approved E11018-G electrode material is atomised and fully cladded into twin-disc rail specimens by Laser Powder Directed Energy Deposition. After the weight loss tests at 1400 MPa, experimental results are fitted with the theoretical adhesion curve modifying FASTSIM coefficients. This adhesion curve is employed to numerically calculate the slip contact area of each test. A non-linear correlation has been found and defined between wear and the slip area including the non-linear zone. This relationship is identified for tribochemical wear for low creepages and delaminative wear for middle and high creepages by surface and metallographic characterisation. The obtained results allow to predict the wear of the additively manufactured E11018-G repair material under wheel-rail contact conditions when the slip area is known.