Prior austenite grain size has a marked effect on the hardenability, strength, and impact toughness properties of steels. This study was conducted in order to understand the effect of prior austenite grain size and morphology on the mechanical properties and abrasive wear performance of an ultra-high strength steel. A commercial quenched 500 HB grade wear-resistant steel was selected for the study: the steel was austenitized at two different temperatures and compared to the original, as-received quenched condition. The resulting mean prior austenite grain size was ranging from 14 μm to 34 μm. The decrease in grain size improved the low-temperature impact toughness properties. A high stress abrasive wear testing method with natural granite abrasives was utilized for the evaluation of abrasive wear resistance. The results suggest that decreasing the prior austenite grain size improves the abrasive wear resistance with similar hardness level martensitic steels. In addition, high-resolution electron backscatter diffraction measurements revealed formation of ultra-fine grain structures in the severely deformed regions of the wear surfaces.
Oskari Haiko, Vahid Javaheri, Kati Valtonen, Antti Kaijalainen, Jaakko Hannula, Jukka Kömi, Effect of prior austenite grain size on the abrasive wear resistance of ultra-high strength martensitic steels, Wear, Volumes 454–455, 2020, https://doi.org/10.1016/j.wear.2020.203336.
The article was made in collaboration with University of Oulu and Tampere Wear Center and it is available open access with this link until July 2020: https://authors.elsevier.com/a/1bCY39q8Nn%7Eov