Micromechanics of composites with shape memory alloy fibers in uniform thermal fields

Conference · Tue Aug 01 04:00:00 EDT 1995

OSTI ID:121788

Birman, V; Saravanos, D A; Hopkins, D A

Analytical procedures are developed for a composite system consisting of shape memory alloy fibers within an elastic matrix subject to uniform temperature fluctuations. Micromechanics for the calculation of the equivalent properties of the composite are presented by extending the multi-cell model to incorporate shape memory alloy fibers. A three phase concentric cylinder model is developed for the analysis of local stresses which includes the fiber, the matrix, and the surrounding homogenized composite. The solution addresses the complexities induced by the nonlinear dependence of the in-situ martensite fraction of the fibers to the local stresses and temperature, and the local stresses developed from interactions between the fibers and matrix during the martensitic and reverse phase transformations. Results are presented for a nitinol/epoxy composite. The applications illustrate the response of the composite in isothermal longitudinal loading and unloading, and in temperature induced actuation. The local stresses developed in the composite under various stages of the martensitic and reverse phase transformation are also shown.

• Research Organization: National Aeronautics and Space Administration, Cleveland, OH (United States). Lewis Research Center
• OSTI ID: 121788
• Report Number(s): N--95-33210; NASA-TM--107011; E--9795; NAS--1.15:107011; AIAA-Paper--95-1210; CONF-950444--; CNN: RTOP 505-63-5B
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COMPOSITE MATERIALS
EPOXIDES
FIBERS
NITINOL
SHAPE MEMORY EFFECT
STRESS ANALYSIS
TEMPERATURE DEPENDENCE