Abrasion resistant machinable white cast iron
AssigneeFalconbridge Limited
InventorRobert J. Dawson
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Abstract
A cast iron alloy composition comprising 2.5-3.5% carbon, 0.5-1.0% manganese, 0.25-1.5% silicon, 13-19% chromium, 0.8-3.0% nickel, balance essentially iron which is machinable in the annealed condition and abrasion resistant in the hardened condition. The alloy may be annealed by furnace cooling, at a rate between 100.degree. C. and 350.degree. C./hr., from the austenitizing temperature, and hardened by air cooling from the austenitizing temperature.
Claims8
A cast iron alloy consisting essentially of about 2.5-3.5% carbon, 0.5-1.0% manganese, 0.25-1.5% silicon, 13-19% chromium, 0.8-3.0% nickel, balance iron and incidental impurities;
- which is abrasion resistant in the hardened condition and machinable in the annealed condition.
A method of heat treating a cast iron alloy consisting essentially of about:
- 2.5-3.5% carbon
- 0.5-1.0% manganese
- 0.25-1.5% silicon
- 13-19% chromium
- 0.8-3.0% nickel
- balance iron and incidental impurities,
- comprising cooling said alloy at a rate between 100.degree. C. and 350.degree. C. per hour from a temperature above the austenitizing temperature so as to produce an annealed machinable alloy having a hardness of less than about 45 Rc.
A method of heat treating a cast iron alloy consisting essentially of about:
- 2.5-3.5% carbon
- 0.5-1.0% manganese
- 0.25-1.5% silicon
- 13-19% chromium
- 0.8-3.0% nickel
- balance iron and incidental impurities,
- comprising air cooling said alloy from a temperature above the austenitizing temperature so as to produce an abrasion resistant alloy having a hardness of at least 60 Rc.
Dependencies are inferred from the claim text.