Residual stress distribution in metal/ceramic composites with graded compositions are fairly well characterized by theoretical models. However, experimental verification is lacking. Furthermore, it is not well understood how the residual stress distribution affects the composite's response to an applied stress. This paper addresses these issues by numerical predictions of stress distributions, and experimentally examining indentation deformation behavior in two ductile/brittle joints with graded microstructures. NiAl/TiB2 and Cu/W are model systems investigated. It is hypothesized that Vickers indentation can be used to probe the residual stress field in these graded composites, provided the ductile phase has a high enough flow stress, and does not substantially relieve the residual stresses. Finite element models which predict thermal residual stresses in graded materials are compared with experimental measurements and observations, and the implications are discussed.
Available at: http://works.bepress.com/christopher-muratore/36/
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