Abstract: A mold system and method for producing a casting. The mold system utilizes multiple channels, each channel comprising a sprue and gating system, to feed the mold cavity at different heights. When a lower portion of the mold is filled, a controller is signaled to initiate filling of the mold through a second channel positioned above the lower portion. This mold system desirably provides the hottest molten metal to the last portion of the casting to freeze with or without the use of risers, eliminating casting defects. The system also enables the controlled pouring of dissimilar metal castings.

Abstract: An improved container and method for forming billets using hot isostatic pressing is provided. The method and container allows for adjusting the volume of the container so as to obtain a billet of the desired shape based on selected powder charge for the container. In addition, the corner of the container can be adjusted to allow for elimination of edge effects and further shape control in the resulting billet.

Abstract: A wind turbine component having a lightweight structure is provided and includes a metallic matrix defining a cavity, metallic foam enclosed within the cavity and a solidification metallurgical bond formed at an entire interface between the metallic matrix and the metallic foam.

Abstract: An improved method and container for forming billets using hot isostatic pressing is provided. The improved method and container have features that control the deformations of the container during the high temperatures and pressures experienced in such processing so as to provide a billet having a predetermined shape such as, for example, substantially parallel, convex, and/or concave sides. Conservations of the powder used for the billet and more efficient use of the container upon the resulting billet can be achieved.

Abstract: Various turbine component preforms are disclosed having near-net shape features. In one embodiment, a turbine casing preform is disclosed. The turbine casing preform includes an as-cast body comprising a partially cylindrical wall section of a turbine casing, the wall section having an inner surface and an outer surface. The turbine casing preform also includes a circumferentially-extending vane slot formed in the wall section on the inner surface. In another embodiment, a turbine nozzle diaphragm preform is disclosed. The turbine nozzle diaphragm preform includes an as-cast body comprising a partially-cylindrical wall section of a turbine nozzle diaphragm having an inner surface and an outer surface. The turbine nozzle diaphragm preform also includes an as-cast, circumferentially-extending seal member projecting from one of the outer surface or inner surface.

Abstract: A method by which properties of a component (18) formed of a ductile iron alloy and having thick sections can be promoted with an austempering process. The method entails casting a ductile iron alloy containing iron, carbon, silicon and alloying constituents. The casting is solidified at a rate that inhibits segregation of the alloying constituents to grain boundaries of the casting, and so that the casting contains graphite nodules having a count of greater than 100 nodules per mm2. The casting is then austempered by heating to an austenitization temperature to yield a microstructure having a single-phase matrix of austenite that contains carbon, and then quenching the casting to an austempering temperature. The casting is held at the austempering temperature for a duration sufficient to yield a microstructure whose matrix is mostly ausferrite and essentially free of martensite and pearlite.

Abstract: Systems and methods are provided for improved brazing. A system includes a gap filling compound (GFC). The GFC includes a brazing alloy. The system also includes a GFC retention screen. The GFC retention screen configured to be disposed over the GFC to retain the GFC within the gap during brazing. The GFC retention screen is also configured to enable gas to escape from the GFC during brazing.

Abstract: A wind turbine component having a lightweight structure is provided and includes a metallic matrix defining a cavity, metallic foam enclosed within the cavity and a solidification metallurgical bond formed at an entire interface between the metallic matrix and the metallic foam.

Abstract: A system for heat treating an alloy steel component includes a first enclosure and a second enclosure opposed to the first enclosure. The first and second enclosures define a chamber around only a portion of the alloy steel component. The system further includes a heating element in the chamber to heat the portion of the alloy steel component. A method for heat treating an alloy steel component includes placing a first enclosure against a first side of the alloy steel component and placing a second enclosure against a second side of the alloy steel component. The method further includes creating a substantially airtight chamber around only a portion of the alloy steel component between the first and second enclosures and heating the portion of the alloy steel component inside the substantially airtight chamber.

Abstract: A method and container for forming billets using hot isostatic pressing is provided. The method and container prevent or minimize the diffusion of metals between a high value powder alloy and the container used for hot isostatic pressing. In one exemplary embodiment, a diffusion barrier is placed on the container between the powder and the container to control diffusion therebetween.

Abstract: An improved method and container for forming billets using hot isostatic pressing is provided. The improved method and container have features that control the deformations of the container during the high temperatures and pressures experienced in such processing so as to provide a billet having a predetermined shape such as, for example, substantially parallel, convex, and/or concave sides. Conservations of the powder used for the billet and more efficient use of the container upon the resulting billet can be achieved.

Abstract: An improved container and method for forming billets using hot isostatic pressing is provided. The method and container allows for adjusting the volume of the container so as to obtain a billet of the desired shape based on selected powder charge for the container. In addition, the corner of the container can be adjusted to allow for elimination of edge effects and further shape control in the resulting billet.

Abstract: A component for wind turbines includes cast austempered ductile iron containing about 3.0 to about 3.8 weight percent carbon, about 1.9 to about 2.8 weight percent silicon, up to about 0.3 weight percent manganese, up to about 0.8 weight percent copper, up to about 2.0 weight percent nickel, up to about 0.3 weight percent molybdenum, about 0.03 to about 0.06 weight percent magnesium, less than about 0.05 weight percent chromium, less than about 0.02 weight percent vanadium, and less than about 0.01 weight percent sulfur. The component is preferably a drive shaft or gearbox component having a mass of more than about 3 tons. A method of manufacturing the component is also provided.

Abstract: A cast article of a ductile iron wherein the ductile iron includes carbon from about 2.8 to 3.7 w/o, silicon from about 3.0 to 3.5 w/o, molybdenum from 0.8 to 1.5 w/o, magnesium from about 0.025 to 0.60 w/o, sulfur less than 0.01 w/o and nickel from about 0.0 to 1.3 w/o, the remaining content being iron is provided. The cast article is suitable for a gas turbine casing. A method of manufacturing a cast article is also provided.