GREEN＇S FUNCTION AND EFFECTIVE ELASTIC STIFFNESS TENSOR FOR ARBITRARY AGGREGATES OF CUBIC CRYSTALS

A closed but approximate formula of Green‘s function for an arbitrary aggregate of cubic crystallites is given to derive the effective elastic stiffness tensor of the polycrystal. This formula, which includes three elastic constants of single cubic crystal and five texture coefficients,accounts for the effects of the orientation distribution function (ODF) up to terms linear in the texture coefficients. Thus it is expected that our formula would be applicable to arbitrary aggregates with weak texture or to materials such as aluminum whose single crystal has weak anisotropy.Three examples are presented to compare predictions from our formula with those from Nishioka and Lothe‘s formula and Synge‘s contour integral through numerical integration. As an application of Green‘s function, we briefly describe the procedure of deriving the effective elastic stiffness tensor for an orthorhombic aggregate of cubic crystallites. The comparison of the computational results given by the finite element method and our effective elastic stiffness tensor is made by an example.     

METHOD OF GREEN’S FUNCTION OF CORRUGATED SHELLS

Introduction Corrugateddiaphragmiswidelyusedaselasticmeasurementelementinprecision instruments.Sometimes,corrugateddiaphragmismanufacturedwithconicorsphericaltaper toadjustthecharacteristicofdiaphragm.Forexample,theshapetaperisoftenusedtoincreasesensitivityofdiaphragmindesignofvacuumdiaphragmforheightmeter.Inmanyengineeringpracticalproblems,controlequationscanbedescribedbyeither differentialequationsorintegralequations.Usually,differentialincreaseserrorandintegral decreaseserrorinnumericalana…