Abstract: A method implemented using a processor based device for simulation based testing of materials, includes selecting a first set of points from a data generated from a design space and generating a stochastic metamodel based on the first set of points. The method also includes determining an uncertainty value based on the stochastic metamodel. The method also includes identifying a second set of points different from the first set of points, from the data generated from the design space, based on the uncertainty value. The method further includes combining the second set of points with the first set of points to generate a third set of points, assigning the third set of points to the first set of points. The method also includes iteratively generating, determining, identifying, combining, and assigning steps till the uncertainty value is less than or equal to a predetermined threshold value.

Abstract: A method implemented using a processor based device for simulation based testing of materials, includes selecting a first set of points from a data generated from a design space and generating a stochastic metamodel based on the first set of points. The method also includes determining an uncertainty value based on the stochastic metamodel. The method also includes identifying a second set of points different from the first set of points, from the data generated from the design space, based on the uncertainty value. The method further includes combining the second set of points with the first set of points to generate a third set of points, assigning the third set of points to the first set of points. The method also includes iteratively generating, determining, identifying, combining, and assigning steps till the uncertainty value is less than or equal to a predetermined threshold value.

Abstract: A method of forming a component from a gamma-prime precipitation-strengthened nickel-base superalloy so that, following a supersolvus heat treatment the component characterized by a uniformly-sized grain microstructure. The method includes forming a billet having a sufficiently fine grain size to achieve superplasticity of the superalloy during a subsequent working step. The billet is then worked at a temperature below the gamma-prime solvus temperature of the superalloy so as to form a worked article, wherein the billet is worked so as to maintain strain rates above a lower strain rate limit to control average grain size and below an upper strain rate limit to avoid critical grain growth. Thereafter, the worked article is heat treated at a temperature above the gamma-prime solvus temperature of the superalloy for a duration sufficient to uniformly coarsen the grains of the worked article, after which the worked article is cooled at a rate sufficient to reprecipitate gamma-prime within the worked article.

Abstract: In accordance with an embodiment of the present invention, a method for reducing residual stress in a nickel-base superalloy article comprising about 40–70% of gamma prime phase and having a gamma prime solvus temperature is disclosed. The method comprises the steps of super-solvus heat treating the superalloy article about 5–40° F. (3–22° C.) above the gamma prime solvus temperature; and holding at the super-solvus heat treatment temperature for about 0.25–2 hours, wherein the heat-treated superalloy article has reduced residual stress.

Abstract: An article made of a nickel-base superalloy strengthened by the presence of a gamma-prime phase is prepared by solution heat treating the nickel-base superalloy at a solutionizing temperature above a gamma-prime solvus temperature of the nickel-base superalloy, thereafter first quenching the nickel-base superalloy in a first molten salt bath maintained at a temperature of from the gamma-prime solvus temperature to about 100° F. below the gamma-prime solvus temperature, thereafter second quenching the nickel-base superalloy in a second molten salt bath maintained at a temperature below an aging temperature of the nickel-base superalloy, and thereafter precipitation heat treating the nickel-base superalloy at the aging temperature to precipitate an aged microstructure having gamma prime phase in a nickel-base matrix.

Abstract: A test method for testing the thermal mechanical fatigue performance of a test material includes preparing a test specimen of the test material, wherein the test specimen has a base, and a rib extending outwardly from the base. The test specimen is thermally cycled through at least one test cycle. In each test cycle the rib is heated to a higher rib temperature and thereafter cooled to a lower rib temperature. The test specimen is evaluated for thermal mechanical fatigue damage.

Abstract: A forging blank of a forging nickel-base superalloy is forged in a forging press having forging dies made of a die nickel-base superalloy. The forging is accomplished by heating the forging blank to a forging-blank starting temperature of from about 1850° F. to about 1950° F., heating the forging dies to a forging-die starting temperature of from about 1500° F. to about 1750° F., placing the forging blank into the forging press and between the forging dies, and forging the forging blank at the forging-blank starting temperature using the forging dies at the forging-die starting temperature, to produce a forging.

Abstract: A process for positioning at least one defect in a billet being forged into an article is described. The size and location of the billet is first determined, using a non-destructive test such as ultrasonic inspection. The movement of the defect under selected forging conditions is then predicted, using a finite element analysis model. The billet can then be positioned and forged under conditions which cause the defect to move to a non-critical area of the article. In this manner, a billet which might otherwise be discarded or set aside can often be retained for a useful purpose. Related articles are also described.

Abstract: A superalloy made of a forging nickel-base superalloy such as Rene™ 88DT or ME3 is forged in a forging press having forging dies made of a die nickel-base superalloy. The forging is accomplished by heating to a forging temperature of from about 1700° F. to about 1850° F., and forging at that forging temperature and at a nominal strain rate. The die nickel-base superalloy is selected to have a creep strength of not less than a flow stress of the forging nickel-base superalloy at the forging temperature and strain rate.

Abstract: A superalloy made of a forging nickel-base superalloy such as Rene™ 88DT or ME3 is forged in a forging press having forging dies made of a die nickel-base superalloy. The forging is accomplished by heating to a forging temperature of from about 1700° F. to about 1850° F., and forging at that forging temperature and at a nominal strain rate. The die nickel-base superalloy is selected to have a creep strength of not less than a flow stress of the forging nickel-base superalloy at the forging temperature and strain rate.

Abstract: A forging blank of a forging nickel-base superalloy is forged in a forging press having forging dies made of a die nickel-base superalloy. The forging is accomplished by heating the forging blank to a forging-blank starting temperature of from about 1850° F. to about 1950° F., heating the forging dies to a forging-die starting temperature of from about 1500° F. to about 1750° F., placing the forging blank into the forging press and between the forging dies, and forging the forging blank at the forging-blank starting temperature using the forging dies at the forging-die starting temperature, to produce a forging.

Abstract: A process for positioning at least one defect in a billet being forged into an article is described. The size and location of the billet is first determined, using a non-destructive test such as ultrasonic inspection. The movement of the defect under selected forging conditions is then predicted, using a finite element analysis model. The billet can then be positioned and forged under conditions which cause the defect to move to a non-critical area of the article. In this manner, a billet which might otherwise be discarded or set aside can often be retained for a useful purpose. Related articles are also described.

Abstract: A gas turbine engine includes a non-rotatable member that includes a honeycomb seal that reduces wear to rotor seal teeth disposed within the gas turbine engine. The gas turbine engine also includes a rotatable annular member including a sealing assembly disposed between rotor and stator components. The rotatable annular member includes seal teeth that extend radially outward from the rotatable annular member. The stator components include a non-rotatable member that includes a honeycomb seal that extends radially inward. The honeycomb seal is fabricated from a material that has a melting temperature less than approximately 2000° F.

Abstract: A gas turbine engine includes a non-rotatable member that includes a honeycomb seal that reduces wear to rotor seal teeth disposed within the gas turbine engine. The gas turbine engine also includes a rotatable annular member including a sealing assembly disposed between rotor and stator components. The rotatable annular member includes seal teeth that extend radially outward from the rotatable annular member. The stator components include a non-rotatable member that includes a honeycomb seal that extends radially inward. The honeycomb seal is fabricated from a material that has a melting temperature less than approximately 2000° F.