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This report includes the Phase I preliminary study in which the Quinlan theory was critiqued, alternate approaches were studied and detailed research planning accomplished. Also included are detailed experimental evaluations of propellant during Phases 2 and 3, the uniaxial/isothermal investigation and the two-dimensional variable temperature investigation. The report also covers the validation of the accuracy of the constitutive theory in a three-dimensional state of stress and strain. Detailed subcontractor theoretical development and predictions are given.

This report details the CSD effort in the design, analysis, manufacturing, calibration, and embedded use of improved normal stress transducers. Prototype transducers from two different contractors were manufactured and tested as well as final production transducer models. Finite element analysis techniques used for transducer analysis are extensively covered and were used for design optimization and gage interpretation. Results covering gaseous nitrogen calibrations, long term stability, self-heating, diode effects, embedded thermal and pressurization loadings, and mechanical tests are presented and compared with design goals. Detialed manufacturing specifications are presented along with recommended calibration and installation techniques. The final transducer design is 0.130-in. high with an external prewired compensation package. Stability of the metal and epoxy bond has been optimized by special processing techniques which are presented. Several significant achievements were obtained during the program. The first computerized design tradeoff curves were generated for stress transducers. Successful electron beam welding of critical components on stress transducers was demonstrated. Transducer measured stress in propellant was verified independently in the tension-compression-shear and TM-1 devices. Transducer response under high rate loading conditions was demonstrated. Agreement between predicted and measured stresses for a thermal loaded solid propellant motor using the thermal-mechanical interaction factor was achieved. (Author), See also Volume 2, AD-A073 660.

This report details the CSD effort in the design, analysis, manufacturing, calibration, and embedded use of improved normal stress transducers. Prototype transducers from two different contractors were manufactured and tested as well as final production transducer models. Finite element analysis techniques used for transducer analysis are extensively covered and were used for design optimization and gage interpretation. Results covering gaseous nitrogen calibrations, long term stability, self-heating, diode effects, embedded thermal and pressurization loadings, and mechanical tests are presented and compared with design goals. Detailed manufacturing specifications are presented along with recommended calibration and installation techniques. The final transducer design is 0.130-in. high with an external prewired compensation package. Stability of the metal and epoxy bond has been optimized by special processing techniques which are presented. Several significant achievements were obtained during the program. The first computerized design tradeoff curves were generated for stress transducers. Successful electron beam welding of critical components on stress transducers were demonstrated. Transducer measured stress in propellant was verified independently in the tension-compression-shear and TM-1 devices. Transducer response under high rate loading conditions was demonstrated. Agreement between predicted and measured stresses for a thermal loaded solid propellant motor using the thermal-mechanical interaction factor was achieved. (Author), See also Volume 1, AD-A073 659.

This report details the technical effort put forth by CSD and its subcontractors during the first three phases of this program for propellant nonlinear constitutive theory extension. This includes the Phase I preliminary study in which the Quinlah theory was critiqued, alternate approaches were studied and detailed research planning accomplished. Also included are the detailed experimental evaluations of propellant during Phases II and III, the uniaxial/isothermal investigation and the two-dimensional variable temperature investigation. Detailed subcontractor theoretical development and predictions are presented.

A second generation finite element computer code was developed with specialized features for accurate evaluation of solid propellant case liner bond regions. The code uses six-term quadratic elements for propellant modeling, special thin liner elements for liner and insulation modeling, and a crack tip element for modeling boots and cracked regions. Mesh generation is automated with variable density spacing and input format is optimized for minimum labor during problem setup. The code contains a rezone feature for selective refining of specific high stress gradient regions and rerunning for maximum accuracy. This new computer code was made available to the solid propellant industry at a computer users course in October 1973. (Modified author abstract)