Sphericity determination using resonant ultrasound spectroscopy
A method is provided for grading production quantities of spherical objects, such as roller balls for bearings. A resonant ultrasound spectrum (RUS) is generated for each spherical object and a set of degenerate sphere-resonance frequencies is identified. From the degenerate sphere-resonance frequencies and known relationships between degenerate sphere-resonance frequencies and Poisson's ratio, a Poisson's ratio can be determined, along with a 'best' spherical diameter, to form spherical parameters for the sphere. From the RUS, fine-structure resonant frequency spectra are identified for each degenerate sphere-resonance frequency previously selected. From each fine-structure spectrum and associated sphere parameter values an asphericity value is determined. The asphericity value can then be compared with predetermined values to provide a measure for accepting or rejecting the sphere. 14 figs.
- Issue Date:
- OSTI Identifier:
- 7173812
- Assignee:
- Univ. of California, Office of Technology Transfer, Alameda, CA (United States) PTO; EDB-94-168673
- Patent Number(s):
- US 5355731; A
- Application Number:
- PPN: US 7-880393
- Contract Number:
- W-7405-ENG-36
- Resource Relation:
- Patent File Date: 8 May 1992
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 42 ENGINEERING; BALL BEARINGS; MACHINE PARTS; SPHERICAL CONFIGURATION; ULTRASONIC TESTING; ROLLER BEARINGS; CALIBRATION; FREQUENCY DEPENDENCE; ACOUSTIC TESTING; BEARINGS; CONFIGURATION; MATERIALS TESTING; NONDESTRUCTIVE TESTING; TESTING; 420500* - Engineering- Materials Testing