Thermal Residual Stress Simulation in Thermoplastic Filament Winding Process

This paper focuses on the reduction of process-related thermal residual stress in fiber metal laminates and its impact on the mechanical properties. Different modifications during fabrication of co-cure bonded steel/carbon epoxy composite hybrid structures were investigated. Specific examinations are conducted on UD-CFRP-Steel specimens, modifying temperature, pressure or using a thermal expansion clamp during manufacturing. The impact of these parameters is then measured on the deflection of asymmetrical specimens or due yield-strength measurements of symmetrical specimens. The tensile strength is recorded to investigate the effect of thermal residual stress on the mechanical properties. Impact tests are performed to determine the influence on resulting damage areas at specific impact energies. The experiments revealed that the investigated modifications during processing of UD-CFRP-Steel specimens can significantly lower the thermal residual stress and thereby improve the tensile strength.

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Development of a Residual Stress Simulation Benchmark for a Single Bead-on-Plate Weldment

Volume 6: Materials and Fabrication ◽

10.1115/pvp2006-icpvt-11-93763 ◽

2006 ◽

Cited By ~ 1

Author(s):

Peter J. Bouchard ◽

Lyndon Edwards ◽

Anastasius G. Youtsos ◽

Roger Dennis

Keyword(s):

Residual Stress ◽

Assessment Procedure ◽

Defect Assessment ◽

Best Estimate ◽

Weld Residual Stress ◽

Single Bead ◽

Stress Prediction ◽

Stainless Steel Bead ◽

Stress Simulation ◽

Network Project

Finite element weld residual stress modelling procedures involve complex non-linear analyses where many assumptions and approximations have to be made by the analyst. Weld modelling guidelines for inclusion in the R6 defect assessment procedure are in preparation and will be accompanied by a series of validation benchmarks that can be used to evaluate the accuracy of weld modelling procedures and assess their suitability for use in fracture assessments. It is intended to base one of the benchmarks on a stainless steel bead-on-plate weldment that has been extensively studied by members of Task Group 1 of the NeT European Network project. This paper uses round robin residual stress measurements from the NeT project to derive a statistically based ‘best estimate’ distribution of transverse stress passing through the wall-section at mid-length of the bead-on-plate weldment. The accuracy of a state-of-the-art residual stress prediction is benchmarked against the best estimate measurements using a root mean square error analysis and comparisons of decomposed components of stress. The appropriateness of using the predicted residual stresses in fracture assessments is assessed by comparing stress intensity factors based on the measured and predicted distributions of stress. The results from these studies will be used to help establish accuracy targets and acceptance criteria for the welding benchmark.

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Effect of thermal residual stress on the reflection spectrum from FBG sensors embedded in CFRP composites

10.1117/12.470709 ◽

2002 ◽

Cited By ~ 1

Author(s):

Yoji Okabe ◽

Shigeki Yashiro ◽

Ryohei Tsuji ◽

Tadahito Mizutani ◽

Nobuo Takeda

Keyword(s):

Residual Stress ◽

Reflection Spectrum ◽

Thermal Residual Stress ◽

Cfrp Composites ◽

Fbg Sensors

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Micromechanical Modeling of Viscoplastic Behavior of Laminated Polymer Composites With Thermal Residual Stress Effect

Journal of Engineering Materials and Technology ◽

10.1115/1.4033070 ◽

2016 ◽

Vol 138 (3) ◽

Cited By ~ 9

Author(s):

Qiang Chen ◽

Xuefeng Chen ◽

Zhi Zhai ◽

Xiaojun Zhu ◽

Zhibo Yang

Keyword(s):

Residual Stress ◽

Polymer Matrix Composites ◽

Micromechanical Model ◽

Thermal Residual Stress ◽

Micromechanical Modeling ◽

Multiscale Approach ◽

Stress Effect ◽

Accurate Analysis ◽

Rate Dependent ◽

Residual Stress Effect

In this paper, a multiscale approach has been developed for investigating the rate-dependent viscoplastic behavior of polymer matrix composites (PMCs) with thermal residual stress effect. The finite-volume direct averaging micromechanics (FVDAM), which effectively predicts nonlinear response of unidirectional fiber reinforced composites, is incorporated with improved Bodner–Partom model to describe the viscoplastic behavior of PMCs. The new micromechanical model is then implemented into the classical laminate theory, enabling efficient and accurate analysis of multidirectional PMCs. The proposed multiscale theory not only predicts effective thermomechanical viscoplastic response of PMCs but also provides local fluctuations of fields within composite microstructures. The deformation behaviors of several unidirectional and multidirectional PMCs with various fiber configurations are extensively simulated at different strain rates, which show a good agreement with the experimental data found from the literature. Influence of thermal residual stress on the viscoplastic behavior of PMCs is closely related to fiber orientation. In addition, the thermal residual stress effect cannot be neglected in order to accurately describe the rate-dependent viscoplastic behavior of PMCs.

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