Nonlinear Effects on Composite Laminate Thermal Expansion.

摘要: Abstract : The thermomechanical behavior of unidirectionally fiber reinforced laminae in plane stress has been described by a set nonlinear stress-strain relations. A general procedure for analysis in-plane loaded symmetric laminates, composed such laminae, established simultaneous loading and temperature inputs. + or -45 deg laminate subjected to heating uniaxial load analyzed detail. Analyses Graphite/Polyimide laminates have shown that the strains cannot be separated into mechanical strain free thermal expansion strain. Consequently coefficient is generally not useful computation laminate. Moreover, as which behaves isotropically anisotropically when heated. Elastic properties coefficients unidirectional specimens were measured function provide inputs analysis. tested obtain under various loads. experimental results demonstrated effects predicted analysis, namely dependence on load, anisotropy load. Numerical agreement analytical was fair. significance time comparison with without 15-day delay at intermediate temperature. (MM)