Damage Zone around Crack Tip for Two-Phase Adhesive Joint with Rubber-Modified Epoxy Resin.

The fracture behavior of an interface crack tip has significant influence on the structural integrity of an adhesive joint. We investigate a damage zone and the deformation of rubber particles around a tip of an interface crack between rubber-modified epoxy resin and aluminum. They are compared with those around a crack tip in homogeneous rubber-modified epoxy resin. Cavitations in rubber particles are observed around a damaged crack tip in homogeneous resin but not around a damaged interface crack tip. Rubber particles around an interface crack tip are deformed ellipsoidally due to the residual stress even before being damaged, and interfaces between rubber particles and epoxy resin around an interface crack tip are debonded after being damaged.

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Damage zone around crack tip and fracture toughness of rubber-modified epoxy resin under mixed-mode conditions

Engineering Fracture Mechanics ◽

10.1016/s0013-7944(01)00151-5 ◽

2002 ◽

Vol 69 (12) ◽

pp. 1363-1375 ◽

Cited By ~ 25

Author(s):

Deok-Bo Lee ◽

Toru Ikeda ◽

Noriyuki Miyazaki ◽

Nak-Sam Choi

Keyword(s):

Fracture Toughness ◽

Epoxy Resin ◽

Mixed Mode ◽

Damage Zone ◽

Crack Tip ◽

Modified Epoxy

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Effect of Bond Thickness on the Fracture Toughness of Adhesive Joints

Journal of Engineering Materials and Technology ◽

10.1115/1.1631433 ◽

2004 ◽

Vol 126 (1) ◽

pp. 14-18 ◽

Cited By ~ 51

Author(s):

Deok-Bo Lee ◽

Toru Ikeda ◽

Noriyuki Miyazaki ◽

Nak-Sam Choi

Keyword(s):

Fracture Toughness ◽

Adhesive Joint ◽

Damage Zone ◽

Crack Tip ◽

Adhesive Layer ◽

Compact Tension ◽

Optical Microscope ◽

Adhesive Joints ◽

Adhesive Layers ◽

Modified Epoxy

The effect of bond thickness on the fracture toughness of adhesive joints was investigated from a microstructural perspective, using compact tension (CT) adhesive-joint specimens with different bond thicknesses. The adhesive material was a rubber-modified epoxy resin with 12.5 wt% carboxy-terminated butadiene acrylonitrile (CTBN) elastomer. The shapes of the rubber particles dispersed in adhesive layers of damaged and undamaged specimens were observed with an optical microscope. The damage was distributed along the interfaces between the adhesive layer and the two adherends. The results show that the primary causes of variations in the fracture toughness of an adhesive joint with the bond thickness are not only a damage zone around a crack tip but also the combination of a damage zone around a crack tip and additional damage zones along the interfaces.

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Damage Zone around Crack Tip and Fracture Toughness of Rubber-Modified Epoxy Resin under Mixed Mode Condition.

Journal of the Society of Materials Science Japan ◽

10.2472/jsms.50.55 ◽

2001 ◽

Vol 50 (1) ◽

pp. 55-61 ◽

Cited By ~ 2

Author(s):

Deok-bo LEE ◽

Toru IKEDA ◽

Noriyuki MIYAZAKI

Keyword(s):

Fracture Toughness ◽

Epoxy Resin ◽

Mixed Mode ◽

Damage Zone ◽

Crack Tip ◽

Modified Epoxy

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Failure Analysis on Rubber-Modified Epoxy Resin under Various Loading Speed Conditions

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.297-300.1907 ◽

2005 ◽

Vol 297-300 ◽

pp. 1907-1912 ◽

Cited By ~ 2

Author(s):

Deok Bo Lee ◽

Joo Hyung Kim

Keyword(s):

Fracture Toughness ◽

Composite Material ◽

Epoxy Resin ◽

Structural Reliability ◽

Fiber Composite ◽

Damage Zone ◽

Crack Tip ◽

Rubber Content ◽

The Matrix ◽

Modified Epoxy

A rubber-modified epoxy resin is widely used as adhesive and matrix materials for fiber composite material. The structural reliability of composite material depends on the fracture toughness of the matrix resin. In this study, the fracture toughness and the damage zone around a crack tip in rubber-modified epoxy resin were investigated. The volume fractures of rubber (CTBN1300×8) in the rubber-modified epoxy resin were 0%, 5% and 15% under several loading speeds. The fracture toughness(KIC) and the fracture energy(GIC) were measured by using 3-point bending specimens. The 4-point bending specimens were also used to observe damage zones at the vicinity of a crack tip in modified resins. The results show that the values of the fracture toughness and the sizes of damage zones at 5% and 15% rubber content decrease with increase in loading speed.

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Preparation and properties studies of UV-curable silicone modified epoxy resin composite system

Journal of Applied Biomaterials & Functional Materials ◽

10.1177/2280800017753053 ◽

2018 ◽

Vol 16 (1_suppl) ◽

pp. 170-176 ◽

Cited By ~ 4

Author(s):

Zhouhui Yu ◽

Aiyong Cui ◽

Peizhong Zhao ◽

Huakai Wei ◽

Fangyou Hu

Keyword(s):

Heat Resistance ◽

Epoxy Resin ◽

Resin Composite ◽

Curing Kinetics ◽

Resin Content ◽

Silicone Resin ◽

Two Phase ◽

Uv Curable ◽

Humidity Resistance ◽

Modified Epoxy

Introduction: Modified epoxy suitable for ultraviolet (UV) curing is prepared by using organic silicon toughening. The curing kinetics of the composite are studied by dielectric analysis (DEA), and the two-phase compatibility of the composite is studied by scanning electron microscopy (SEM). Methods: The tensile properties, heat resistance, and humidity resistance of the cured product are explored by changing the composition ratio of the silicone and the epoxy resin. Results: SEM of silicone/epoxy resin shows that the degree of cross-linking of the composites decreases with an increase of silicone resin content. Differential thermal analysis indicates that the glass transition temperature and the thermal stability of the composites decrease gradually with an increase of silicone resin content. The thermal degradation rate in the high temperature region, however, first decreases and then increases. In general, after adding just 10%–15% of the silicone resin and exposing to light for 15 min, the composite can still achieve a better curing effect. Conclusions: Under such conditions, the heat resistance of the cured product decreases a little. The tensile strength is kept constant so that elongation at breakage is apparently improved. The change rate after immersion in distilled water at 60°C for seven days is small, which shows excellent humidity resistance.

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