| Popis: |
Even though it has been in use for a very long time, the high chromium white cast iron (HCWCI) still triggers scientists due to its outstanding wear resistance. Besides its well-known as-cast usage, it can be used as a coating material, as well. HCWCI owes this feature due to the presence of carbides in microstructure, which depends on the composition and heat treatment regime. This investigation was conducted on two HCWCI alloys, where in addition to chromium, the second important alloying element is molybdenum (Mo). Apart from other alloying elements, HCWCI_1 is alloyed with 24.48% Cr and 1.32% Mo, while HCWCI_2 contains 14.11% Cr and 2.47% Mo. The comprehensive microstructural characterization was carried out on as-cast samples and samples obtained after quenching (at -196oC) and/or quenching followed by tempering (at 250oC). Important microstructure indicators are: the stability of austenite, the ratio of microconstituents (especially different types of carbides), as well as their arrangement and morphology, so they are revealed and discussed in relation to the influencing mechanical properties. |
