Effect of Vanadium Addition on the Surface Roughness and Fatigue Crack Propagation in a Railroad Wheel Using Twin Disc Wear Test

Abstract

To verify the effect of 0.13 % vanadium addition (% in weight) on the wear resistance of a railroad wheel steel with 0.7 % carbon, twin-disc rolling-sliding test were performed. These two steels were named 7V and 7C. The test discs were analyzed to verify the superficial conditions and wear mechanisms using SEM (Scanning Electron Microscopy) and roughness measurements. After 100,000 cycles running it was concluded that without the presence of debris, the 7V steel presented a reduction in 35 % the mass loss compared to 7C steel. For the 7V steel, in the test without debris, the discs presented small cracks (10 μm long), very near (3 μm deep) the surface, but in the test with the presence of debris, the disc surfaces presented delaminated material and long cracks (100 μm long) faraway from surface (up to 72 μm deep). The presence of debris also increased the roughness parameters in 7V steel: average Rz jumped from near 6 μm in the steel without debris to near 26 μm in the steel with debris.

Research on wear performance of new type CL60 steel for metro wheel

“…Zhang et al (2019) studied the microstructure, hardness and sliding wear behavior of bainitic steel containing 1.0%-2.5% Si, and demonstrated that the wear loss of cast steel decreased with increasing Si content. The wear tests on wheel steels performed by Rezende et al (2019) showed that the 7 V wheel steel had higher wear resistance due to addition of vanadium (V). In light of the demand for high hardness wheels for 35-40 t axle load, Jiang et al (2013) designed four types of steels by Si-Cr microalloying.…”