Store | Help | Jobs | Print Page | Contact Us | Sign In | Create Account
Online Store: CAMX 2016 - Anaheim, CA - September 26-29 / 2016
Main Storefront
        

Experimental and Computational Investigations into the Effect of Process

Item Options
Sign in for your pricing!
Price: $36.00
Quantity: *
 
Description

 

Experimental and Computational Investigations into the Effect of Process Induced Stresses on the Mode I Fracture Toughness of Composite Materials

 

Process induced residual stresses commonly occur in composite structures composed of dissimilar materials. These residual stresses form due to differences in the composite materials’ coefficients of thermal expansion as well as the cure shrinkage exhibited by polymer matrix materials. These residual stresses can have a profound effect on the measured performance of a loaded composite structure. A material property of particular interest when modeling the formation of damage in composite materials is the mode I fracture toughness.  Currently, the standard method of measuring the mode I fracture toughness involves a double cantilever beam (DCB) experiment, where a precrack is introduced into a laminate and subsequently opened under tension. The resulting apparent fracture toughness from the DCB experiment may depend upon a coupled interaction between a material property, the mode I energy release rate, and the effect of residual stresses.  Therefore, in this study, a series of DCB experiments are completed in conjunction with the solution of representative finite element models to quantify and understand the effect of process-induced residual stresses and temperature variations on the apparent fracture toughness. Specifically, double cantilever beam experiments are completed at three temperatures to characterize three types of specimens composed of carbon fiber/epoxy and glass fiber/epoxy materials: carbon bonded to carbon, glass bonded to glass, and carbon bonded to glass. The carbon-to-carbon and glass-to-glass specimens provide estimates of the composite’s fracture toughness in the absence of significant residual stresses and the carbon-to-glass specimens indicate the effect of measurable process induced stresses. Upon completion of testing, the measured results and observations are used to develop high-fidelity finite element models simulating the residual stresses formed throughout the manufacturing process and the subsequent DCB testing of a laminate composed of the carbon/epoxy and glass/epoxy materials. The stress fields and delamination behavior predicted through simulation assist in understanding the trends observed during the DCB experiments and demonstrate the important relationship between experimental and computational efforts.

 

Authors: Stacy M. Nelson and Brian T. Werner

 

Conference: CAMX 2016 – Anaheim

 

SKU/Code: TP16-0050

 

Pages: 18

 


 


Platinum Corporate Partners

Find Us

21680 Gateway Center Drive
Suite 300
Diamond Bar, CA 91765-2454

P: +1.626.521.9460