Patent ID: 11873545
Assignee: WEIR MINERALS AUSTRALIA LTD.
Field: Materials, metallurgy (Chemistry)
Classification: CPC C | IPC C

Claim 0:
1. A casting of a hypereutectic white iron that, in an as-cast form of the casting, has a microstructure that includes a ferrous matrix that contains 12-20 wt. % chromium in solution in the matrix, eutectic carbides dispersed in the matrix, primary carbides dispersed in the matrix, and optionally secondary carbides dispersed in the matrix, where the eutectic carbides are 15-25 vol. % of the casting, the primary carbides are 25-35 vol. % of the casting, and when present, the secondary carbides are up to 6 vol. % of the casting,
wherein the ferrous matrix also comprises C: 0.2-1.5 wt. % and Mn: 1.0-5.0 wt. %;
wherein the eutectic carbides, the primary carbides, and the secondary carbides consist of M7C3 carbides, where “M” comprises Cr, Fe, and Mn;
wherein the weight ratio of chromium and carbon in the casting is greater than 8:1 and less than 9.25:1; and
wherein the bulk chemistry of the casting comprises: >37-40 wt. % Cr, 4-5 wt. % C, 1-3 wt. % Mn, <1.5 wt. % Si, and balance Fe and impurities.