Accession Number : ADA260828


Title :   Thermomechanical Response of Shape Memory Composites


Descriptive Note : Technical rept.


Corporate Author : RENSSELAER POLYTECHNIC INST TROY NY DEPT OF CIVIL ENGINEERING


Personal Author(s) : Boyd, James G ; Lagoudas, Dimitris C


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a260828.pdf


Report Date : 18 Jan 1993


Pagination or Media Count : 20


Abstract : The Mori-Tanaka micromechanics method is used to predict the effective properties of composite materials consisting of a polymer matrix reinforced by a fiber made of a transformation shape memory effect (SME) material. The composite response is plotted for combinations of the following scenarios: (1) isothermal longitudinal and transverse stress input, (2) stress- free thermal loading, (3) constant fiber thermoelastic properties, and (4) thermoelastic fiber properties that vary with the martensite volume fraction. For the case of an isothermal stress input, the composite transformation stress, the maximum transformation strain, and the hysteresis are all reduced vis-a-vis the monolithic SME material. In contrast to a monolithic SME material, stress- free thermal loading of a SME composite can produce a transformation strain. It is shown that closed form solutions for the effective martensite and austenite start temperatures can be derived, that they are sensitive to the stress-free reference temperature of the fiber, and that the stress-free austenite and martensite start temperatures are higher than those of the monolithic SME material.


Descriptors :   *THERMOMECHANICS , *COMPOSITE MATERIALS , STRESSES , SCENARIOS , TEMPERATURE , VOLUME , VIBRATION , THERMODYNAMICS , POLYMERS , FIBER REINFORCED COMPOSITES , MATRIX MATERIALS , AUSTENITE , MECHANICS , CONSTANTS , MICROMECHANICS , HYSTERESIS , TRANSFORMATIONS , TRANSVERSE , MARTENSITE , THERMOELASTICITY


Subject Categories : Laminates and Composite Materials
      Metallurgy and Metallography
      Mechanics
      Thermodynamics


Distribution Statement : APPROVED FOR PUBLIC RELEASE