Patent application number | Description | Published |
20130115092 | ISOTHERMAL STRUCTURAL REPAIR OF SUPERALLOY COMPONENTS INCLUDING TURBINE BLADES - Structural repair of cracks and other defects in superalloy components, such as steam or gas turbine blades in stationary or aero gas turbines, are performed by heating the blade substrate to an isothermal hold temperature below the substrate's incipient melting point and filling the crack with molten superalloy filler material. The molten filler solidifies into a casting and bonds with the component substrate at the isothermal hold temperature. Heat treatment processes are completed, so that the former crack is filled with cast superalloy material having identical or similar structural properties as the adjoining substrate superalloy material. The casting repair method may be utilized universally for all types of superalloy component defects, including those previously repaired by cosmetic, lower strength welding or brazing methods. | 05-09-2013 |
20130302647 | LOW MELTING POINT BRAZE ALLOY FOR HIGH TEMPERATURE APPLICATIONS - A multi component braze filler alloy is described having a melting temperature less than about 1235 deg. C. and greater than about 1150 deg. C. This alloy can be processed by hot isostatic pressing (HIP) at a temperature above about 1065 deg. C. and is particularly suited for the repair of gas turbine blades and vanes, especially those made from alloy 247. The relatively low Ti content in the present braze alloy tends to form less MC carbides at the joint interface, particularly in comparison with other braze alloys high in Zr and/or Hf. | 11-14-2013 |
20130319580 | LASER ADDITIVE REPAIRING OF NICKEL BASE SUPERALLOY COMPONENTS - Ni base superalloy components containing relatively large amounts of Al and Ti are known to be difficult to build up by a weld build up process without cracking. As the Al and Ti content of the superalloy is increased to improve the strength, the susceptibility to cracking is increased. It is shown herein that reducing the γ′ phase in the additive built up material improves robustness against cracking. A stepwise, controlled heating and cooling process is described to be used in cooperation with an additive build up process to reduce the γ′ present and thereby reduce cracking. | 12-05-2013 |
20140209576 | USE OF ELEVATED PRESSURES FOR REDUCING CRACKS IN SUPERALLOY WELDING AND CLADDING - A superalloy component, such as gas turbine blade or vane, is structurally welded by placing the component in an isolation chamber. Inert gas is introduced into the chamber. The substrate is welded in the chamber, creating a weld zone. Pressure is applied directly on the weld zone that is greater than atmospheric pressure. Application of such pressure increases the weld zone ductility and reduces likelihood of solidification cracking and strain age cracking, compared to weld zones formed at atmospheric pressure. In some embodiments an isostatic pressure chamber is used to apply isostatic pressure on the weld zone. In other embodiments the welding is performed by laser welding or cladding, TIG welding electron beam welding or autogenous welding. | 07-31-2014 |
20140272450 | NEAR EUTECTIC COMPOSITION NICKEL BASE SANDWICH BRAZE FOIL - A braze foil ( | 09-18-2014 |
20150050157 | HOLD AND COOL PROCESS FOR SUPERALLOY JOINING - Ni base superalloys containing relatively large amounts of Al and/or Ti are known to be difficult to weld satisfactorily. As the Al and Ti content of the superalloy is increased to improve the strength, the weldability of the component is drastically reduced. It is concluded herein that reducing the γ′ phase improves weldability. A stepwise, controlled heating and cooling process is described to be used in cooperation with a welding process to reduce the γ′ present and thereby improve weldability. | 02-19-2015 |
20150107072 | FATIGUE RESISTANT TURBINE THROUGH BOLT - A fatigue resistant turbine through bolt formed from a base material covered by a first surface modification and a second surface modification is disclosed. The first surface modification may be in contact with the base material and, in at least one embodiment, may be a low plasticity burnished layer that increases the residual compressive stresses on an outer surface of the turbine through bolt. The second surface modification may cover the first surface modification and, in at least one embodiment, may be a spinel oxide layer on the low plasticity burnished layer. The second surface modification may be positioned on the first surface modification or on the bare turbine through bolt contact surface without low plastiocity burnishing on the shaft of the turbine through bolt. The first and second surface modifications reduce the likelihood of fretting fatigue failures. | 04-23-2015 |