Abstract: A waveform generator and a signal analyzer are respectively provided in electrical communication with an input transducer and an output transducer capable of conversion between electrical and acoustic signals, and in mechanical communication with a part. A processor coupled with the waveform generator and signal analyzer receives a set of parameters defining a frequency scan from which it determines a number of frequency sweeps to be performed by the waveform generator. Each of the frequency sweeps has a number of frequencies less than a maximum capacity of the waveform generator, and for each frequency sweep, the processor instructs the waveform generator to excite the input transducer and synchronously receiving a response signal with the signal analyzer at multiple frequencies.

Abstract: A waveform generator and a signal analyzer are respectively provided in electrical communication with an input transducer and an output transducer capable of conversion between electrical and acoustic signals, and in mechanical communication with the part. A processor coupled with the waveform generator and signal analyzer receives a set of parameters defining a frequency scan from which it determines a number of frequency sweeps to be performed by the waveform generator. Each of the frequency sweeps has a number of frequencies less than a maximum capacity of the waveform generator, and for each frequency sweep, the processor instructs the waveform generator to excite the input transducer and synchronously receiving a response signal with the signal analyzer at multiple frequencies.

Abstract: Modal frequencies of known good sample parts (SN) are analyzed to determine a pattern which will identify acceptable material and dimensional variations. The data obtained by analysis is then archived. Production parts are then measured at the modal frequencies and the production parts are accepted or rejected after pattern analysis of each part by comparing the production part with response to the pattern identified as acceptable for material and dimensional variations. Production part data is archived for future testing. This procedure is repeated throughout the lifetime of a part, and may be used on parts which are part of an assembly, including other unmeasured parts.

Abstract: Methods for the prediction of the frequency of high order resonant ultrasound spectroscopy (RUS) diagnostic modes are used to limit the band width of diagnostic testing at high order mode frequencies. Testing of parts at low order frequency modes is used to calculate part dimensions, and then these calculated part dimensions are used to predict high order diagnostic mode frequencies. Lower order mode frequencies are used to predict high order diagnostic mode frequencies.

Abstract: A method for temperature compensation of resonant frequency measurements of parts uses Temperature Functions which are mathematical relationships between measured resonant frequencies and temperature. The Temperature Function is used to adjust frequencies measured at any temperature to a resonant frequency at a pre-determined reference temperature. The temperature of a surrogate part or specimen can be measured to eliminate the need to touch a part being tested where the surrogate part has essentially the same dimensions and material properties and is positioned and mounted such that its temperature is essentially the same as the part being tested. The temperature function may be in the form off.sub.r =f.sub.m *(1+(T.sub.m -T.sub.r)/C)where f.sub.r is the resonant frequency compensated to the reference temperature, f.sub.m is the measured resonant frequency, T.sub.m is the measured temperature and T.sub.r is the reference temperature.

Abstract: A part undergoing resonant ultrasound testing is simultaneously driven at a plurality of resonant test frequencies. The response of the part is measured simultaneously. There may be one or more driving transducers and one or more vibration sensing transducers.

Abstract: A method of resonant ultrasonic measurement frequencies to determine materials properties is combined with the use of a finite element model and empirical data made from an actual prototype part to create a validated finite element model. The validated finite element model is then used as a standard for comparison to additional production parts, and production part measurement data is stored and archived by part serial number for future comparison to part tests performed during periodic maintenance of equipment utilizing the part after shipment to customer.

Abstract: Methods for the prediction of the frequency of high order resonant ultrasound spectroscopy (RUS) diagnostic modes are used to limit the band width of diagnostic testing at high order mode frequencies. Testing of parts at low order frequency modes is used to calculate part dimensions, and then these calculated part dimensions are used to predict high order diagnostic mode frequencies. Lower order mode frequencies are used to predict high order diagnostic mode frequencies.

Abstract: A method is provided for detecting resonant ultra sound (RUS) Spectroscopy peaks which is based upon taking the second derivative of the RUS spectrum. The second derivative provides a more sensitive analysis tool, and makes it possible to separate and distinguish peaks in the spectrum which are not readily discernable by other analyses of the spectrum. Analysis criteria such as cut off heights and Z-widths provide judgment criteria for identification of resonant peaks.