Accession Number : AD0615810

Title :   EFFECTS OF EXTERNAL FORCES ON VIBRATING CRYSTAL PLATES.

Descriptive Note : Quarterly rept. no. 7, 1 Nov 64-31 Jan 65,

Corporate Author : LOWELL TECHNOLOGICAL INST RESEARCH FOUNDATION MASS

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

Report Date : 31 JAN 1965

Pagination or Media Count : 49

Abstract : Reactions of oscillating quartz piezoids to external application of forces and torques are considered. Measurements of frequency deviations under tension made at 90 degrees in AT plates exhibit a linearity with respect to applied force at relatively large loads. Results on overtone modes and at higher fundamental frequencies are discussed. A comparison is made of the extent of higher-amplitude areas on the major surfaces of a piezoid when excited at an overtone frequency and at the fundamental resonance. A trend is reported in the motional parameters as the tensional load is increased. Tensile stress coefficients of frequency for the BT cut are established for circular and for rectangular plates, at 0 degrees and 90 degrees, and for fundamental and overtone excitation. Comparisons are drawn with AT-cut cases. Experiments are reported dealing with a change in surface temperature of a vibrating plate when a substantial load is applied. Preliminary experiments on the effects of producing a torsional stress are described. The equations of motion of the plate including thirdorder terms were found. (Author)

Descriptors :   (*QUARTZ, STRESSES), (*VIBRATION, STABILITY), DEFORMATION, COMPRESSIVE PROPERTIES, TENSILE PROPERTIES, FREQUENCY, PIEZOELECTRIC CRYSTALS, SHEAR STRESSES, STRAIN(MECHANICS), QUARTZ RESONATORS

Distribution Statement : APPROVED FOR PUBLIC RELEASE