High-strength and high-toughness cast steel for propellers and method for making propellers of said cast steel

Abstract

Abstract A method of making a high strength, high toughness cast steel marine propeller comprised of not more than 0.25 percent of carbon, not more than 1 percent of silicon, not more than 3 percent of manganese, from 5-20 percent of chromium, from 1-8 percent of cobalt, and from 0.5-7 percent of one or both of molybdenum and tungsten, and the remainder consisting of iron. In addition, the cast steel may contain up to 8 percent of nickel and up to 4 percent of copper, depending on the conditions. The method comprises casting the propeller into individual sections, welding said sections together, heating to a temperature of 800* to 1,000* C. and air cooling. The propeller can be aged by heating to a temperature between 450* and 700* C. If desired, the individual cast sections can be annealed prior to welding.

Inventors

• 👤 Teishiro Oda
• 👤 Makoto Nakamura
• 👤 Masato Zama

Bibliographic Details