Accession Number : AD0488575

Title :   EFFECTS OF EXTERNAL FORCES (TRANSIENT AND PERMANENT).

Descriptive Note : Final rept. 3 May 65-2 May 66,

Corporate Author : LOWELL TECHNOLOGICAL INST RESEARCH FOUNDATION MA

Personal Author(s) : Mingins, Charles R. ; Perry, Robert W. ; Barcus, Luther C.

Report Date : SEP 1966

Pagination or Media Count : 71

Abstract : The investigations dealt with comprise the behavior of frequency deviations caused in oscillating quartz piezoids by the setting up of flexural, compressional, tensile, torsional, and shearing stresses. The relationship of stress coefficient and force coefficient of frequency ar re-examined. Numerous cases of superimposed stresses produced by combinations of forces are reviewed against the background of new observations. Transient effects accompanying sudden changes in stress are considered in the light of such variables as plate size, mode of vibration, magnitude and rapidity of the force change, and type of mechanical connection between the crystal and the load. Various aspects of the previous findings in nonlinear theory in this laboratory are reviewed in the course of adapting the numerical values of the nonlinear third order coefficients for quartz as reported by Thurston et al, to the experimental Y-cut data of Ballato and Bechmann.

Descriptors :   *VIBRATION), (*QUARTZ, (*STRESSES, VIBRATION), (*FORCE(MECHANICS), THEORY), SHEAR STRESSES, SENSITIVITY, COMPRESSIVE PROPERTIES, EQUATIONS.

Subject Categories : Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE