Abstract: A method and system for determining the fiber volume fraction of a composite structure. The system includes a unit for ultrasonically determining the porosity volume fraction in the article, and a unit for calculating the volume fraction of the fibrous reinforcement material in the article based on the porosity volume fraction in the article and the mass densities of the article and the fiber and matrix materials within the article. The method entails determining the mass density of the article, obtaining the mass densities of the fiber material and the matrix material, ultrasonically determining the porosity volume fraction in the article, and then calculating the volume fraction of the fibrous reinforcement material in the article based on the porosity volume fraction in the article, the mass density of the article, the mass density of the matrix material, and the mass density of the fiber material.

Abstract: A method of processing a rotor. The rotor is formed by casting an ingot to have first and second regions formed of different alloys that intermix during casting to define a transition zone therebetween. The ingot is forged to yield a rotor forging that contains axially-aligned first and second alloy regions and a transition zone therebetween. A three-dimensional approximation of the transition zone is generated, which can be used to predict the effects of the transition zone on the dynamic performance of a rotor machined from the forging.

Abstract: A monolithic rotor comprising first and second rotor regions axially aligned within the monolithic rotor and a transition zone therebetween. The first and second rotor regions are formed of different alloys and the transition zone having a composition that differs from and varies between the first and second rotor regions. The first rotor region is located within a high pressure region of the monolithic rotor and is formed from an alloy chosen from the group consisting of CrMoV low alloy steels, martensitic stainless steels containing about 11 to about 14 weight percent chromium, Fe—Ni alloys, and nickel-base alloys. The second rotor region is located within a low pressure region of the monolithic rotor and is formed from an alloy chosen from the group consisting of NiCrMoV low alloy steels and martensitic stainless steels containing about 11 to about 14 weight percent chromium.

Abstract: A method to determine a depth of an internal feature in a forging using an ultrasonic transducer including: collecting data on echoes reflected by the internal feature of ultrasonic signals transmitted into the forging; correcting the collected data to compensate for attenuation of the echoes and signals in the forging, and determining a depth of the internal feature in the forging.

Abstract: A system and method that allows for the immersion ultrasonic inspection of test samples that cannot be immersed in a fluid (e.g., water) bath. A test sample is encapsulated in a sealed evacuated bag made of nonporous flexible material. A portion of the nonporous flexible material is in contact with the surface area of the test sample where the ultrasound wave or beam will impinge. Then the sealed bag with test sample inside are immersed in an acoustic coupling medium, as is an ultrasonic transducer. The transducer is directed to transmit an interrogating ultrasound wave or beam through the vacuum bag into the component being inspected at the area of interest. The sealed bag prevents contact between the inspected component and the acoustic coupling medium.

Abstract: A system and method that allows for the immersion ultrasonic inspection of test samples that cannot be immersed in a fluid (e.g., water) bath. A test sample is encapsulated in a sealed evacuated bag made of nonporous flexible material. A portion of the nonporous flexible material is in contact with the surface area of the test sample where the ultrasound wave or beam will impinge. Then the sealed bag with test sample inside are immersed in an acoustic coupling medium, as is an ultrasonic transducer. The transducer is directed to transmit an interrogating ultrasound wave or beam through the vacuum bag into the component being inspected at the area of interest. The sealed bag prevents contact between the inspected component and the acoustic coupling medium.

Abstract: A transducer position adjustment method, performed to compensate for initial ultrasonic beam alignment error, includes the steps of providing a manipulator of an ultrasonic immersion testing system having a pointing direction and supporting a transducer generating an ultrasonic beam, providing a calibration body defining a target thereon, immersing the transducer of the manipulator and the calibration body in a coupling fluid in an immersion tank of the system, setting the manipulator initially at a first position such that the pointing direction of the manipulator is aligned with the calibration body target at known coordinates, and adjusting the manipulator subsequently to a second position such that the ultrasonic beam of the transducer is brought into alignment with the calibration body target at the known coordinates for initiating an inspection of a test object after replacing the calibration body with the test object.