The effect of thermal spiking on moisture absorption, mechanical and viscoelastic properties of carbon fibre reinforced epoxy laminates

Influence of Hygrothermal Conditioning on the Elastic Properties of Carall Laminates

“…observed. Initial failure can only observed when they occur in constrained regions, such as the tabbed region of the specimen following premature failure initiation by end crushing [15]. Early failures and discernible failure patterns occur in regions where an additional shear stress component is added to the direct compressive normal stress component.…”

“…The moisture absorption from the atmosphere usually occurs through the surface followed by a diffusion process through the bulk of the material. The moisture absorbed consists of water molecules or group of molecules linked by hydrogen bonds to the polymer matrix [15]. On the other hand, moisture can also be transported to the bulk of the composite specimens by the capillary action through microcracks at the fiber-matrix interfaces.…”

“…These factors can affect the thermal and mechanical properties of the composites in different ways during the service life [22]. There is sufficient experimental evidence to believe that the presence of water induces swelling of the system and a build-up of residual stresses, rupture of adhesive bonding between the system and a given substrate and modification of the local stress state and creation of microcrazes [23][24][25][26]. Several mechanisms have been proposed for the introduction of water such as: diffusion governed by Fick's relation [15] through the free volume of the polymer; diffusion by osmotic swelling limited by polymer creep, and osmotic phenomena due to the presence of micropores, channels and other defects in the polymer [22].…”

“…Depending on application, materials may be subjected to various types of mechanical stresses and environmental attacks [14][15][16][17][18][19][20][21]. Composites are not an exception.…”

Improvement of Mechanical and Thermal Properties of CFRP Laminates Using Micro-Fibrillated Cellulose

“…called viscoelastic behavior, not only above the glass transition temperature T g but also below T g [1][2][3][4][5][6] . Recent studies are concerned that nanoscale cellulose fiber, called micro-fibrilated cellulose (MFC), is an interesting green reinforcing agent for the production of composite materials.…”