Electric Power Research Institute Incorporated

Bohler Gesellschaft M.b.h.

Robert I Jaffee

Richard L Bodnar

Johann Fladischer

Johann Mayerhoffer

Heimo Jager

Herbert H Puschnik

A modified 1% CrMoV steel of particular use in steam and gas turbine rotors contains from about 0.20 percent to about 0.35 percent carbon, less than about 0.1 percent manganese, from about 1.5 percent to about 6.5 percent nickel, from about 0.8 percent to about 2.0 percent chromium, from about 0.9 percent to about 2.0 percent molybdenum, from about 0.1 percent to about 0.4 percent vanadium, from zero to about 0.07 percent columbium, less than about 0.12 percent silicon, less than about 0.006 percent phosphorus, less than about 0.002 percent sulfur, less than about 0.005 percent antimony, less than about 0.010 percent arsenic, less than about 0.010 percent tin, less than about 0.10 percent copper, less than about 0.010 percent aluminum, balance iron totalling 100 percent, with all percentages by weight. Selected compositions of this steel can be processed to have a 50% fracture appearance transition temperature of less than ambient temperature, and do not exhibit temper embrittlement after extended periods of elevated temperature exposure. The hardenability and creep rupture properties of the modified steel are better than, or equivalent to, those of the standard 1% CrMoV steels, which are brittle at ambient temperatures and subject to temper embrittlement.

Modified 1% CrMoV rotor steel

A method of manufacturing a titanium alloy, wherein a melted and possibly preformed part is annealed to set the starting grain structure, wherewith a first grain structure transformation is accomplished by a first cooling step, whereafter high dislocation densities are produced in the course of a hot forming step, whereupon heat treatment involving a recrystallization is carried out, wherewith in the course of a subsequent cooling a predominantly or substantially martensitic breakdown is achieved, wherewith a grain structure transformation is carried out in a subsequent annealing process, and wherewith in the course of a subsequent chilling a fine grain structure is set. At least the first cooling step is accomplished by spraying the preformed part with water and/or water-air mixtures. A spray device may be used for carrying out the method.

Method of and a spray for manufacturing a titanium alloy

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Palo Alto, CA, United States of America

Robert I Jaffee