Showing papers on "Micromechanics published in 1978"
01 Jan 1978
TL;DR: In this article, the impetus of composite mechanics on composite test methods and/or on interpreting test results is described by using examples from composite micromechanics, composite macromechanical and laminate theory.
Abstract: The impetus of composite mechanics on composite test methods and/or on interpreting test results is described by using examples from composite micromechanics, composite macromechanics and laminate theory. The specific examples included contributions such as criteria for selecting resin matrices for improved composite strength, the 10 deg off-axis tensile test, criteria for configuring hybrids and superhybrids for improved impact resistance and the reduced bending rigidities concept for buckling and vibration analyses.
3 citations
30 Nov 1978
TL;DR: In this paper, a composite durability characterization program is demonstrated which effectively combines preventative nondestructive evaluation (PNDE) with environmental failure and micromechanics analysis of composite structural reliability.
Abstract: : An investigation has been completed which determines the physiochemical mechanisms of environmental durability and degradation of graphite-epoxy (Thornel T300 in 5208 epoxy) and fiber glass-epoxy S-2 glass in 5208 epoxy) under hydro-thermal (high moisture and temperature) exposure. Surface energy and moisture diffusion analysis provide nondestructive test methods which detect irreversible degradatiion of the fiber-matrix interface. Dynamic mechanical damping detects reversible volumetric plasticization effect on modulus, and the interlaminar shear strength and transfibrous fracture energy distributions. A composite durability characterization program is demonstrated which effectively combines preventative nondestructive evaluation (PNDE) with environmental failure and micromechanics analysis of composite structural reliability.
3 citations
TL;DR: In this article, the influence of uniform rubber modulus on the shape of an inflated tire carcass was investigated, and it was concluded that the strain and time dependence of the rubber model will introduce some error in a tire structural analysis that uses linear elastic stress-strain equations and permits geometric nonlinearity.
Abstract: Uniaxial stress tests were conducted on composite specimens cut from two different locations on a bias tire carcass. These data together with cord data, the Halpin‐Tsai “micromechanics” equations, and the linear laminate constitutive equations are used to derive the in‐situ rubber modulus as a function of time and to check for consistency among the specimens tested. The main purpose of the first part of the study was to obtain constituent material properties for use in a finite element model of a tire. This model is then employed in the investigation of the influence of uniform rubber modulus on the shape of an inflated tire carcass, and it is concluded that the strain and time dependence of the rubber modulus will introduce some error in a tire structural analysis that uses linear elastic stress‐strain equations and permits geometric nonlinearity. It appears that the error will be minimal in a low strain region such as in the sidewall.