Carbide Fragmentation and Dissolution in a High-Carbon High-Chromium Steel Using Hot Rolling Process: Microstructure Evolution, Wear, High-Temperature Oxidation, and Chloride-Induced Corrosion Properties

A series of hot rolling processes with different reduction percentages (10%, 30%, and 50%) were applied to a high-carbon high-chromium tool steel (2HCTS). Microstructural evolutions, wear behavior, high-temperature oxidation, and aqueous corrosion properties were investigated. The results revealed the breakage and dissolution of primary carbides and a uniform carbide distribution after the hot rolling process. It was proposed that the presence of higher amounts of dissolved chromium in the hot rolled samples leads to the formation of Cr-rich oxides with more protection and less porosity at high temperatures, as well as an improved corrosion behavior in 3.5 wt% NaCl solution. This improvement in the corrosion behavior is not at the expense of the degradation of wear resistance. Probable mechanisms for carbides dissolution are also discussed.