Strength of Three-Point-Bending Ductile Adhesive Joint with Dissimilar Adherents

In this study, an experimental investigation was conducted in order to determine the effect of different adhesive thickness (i.e., 0.1, 0.5, 0.7 and 1 mm) on strength of ductile adhesive joint. The study scope covers both experiment and analysis. In particular, two different types of material, aluminum and stainless steel as adherents were used and joined by using a specific adhesive jig. By using universal tensile machine (UTM), three-point-bending (3PB) test was conducted. To obtain the result from the experiment, continuous load is applied to the adhesive until the adhesive become fracture. The result obtained has enabled the clarification of failure behavior mechanisms and characteristics of adhesive bonding.

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Strength of Adhesive T-Joint under Moisture Condition

Materials Science Forum ◽

10.4028/www.scientific.net/msf.819.437 ◽

2015 ◽

Vol 819 ◽

pp. 437-442

Author(s):

S. Nurhashima ◽

M. Afendi ◽

B. Izzawati ◽

A. Nor ◽

A.R. Abdullah ◽

...

Keyword(s):

Stainless Steel ◽

Water Temperature ◽

Adhesive Bonding ◽

Moisture Absorption ◽

Failure Load ◽

Perforated Plate ◽

Weight Percent ◽

Epoxy Adhesive ◽

Moisture Condition ◽

Adhesive Thickness

In this study, an experimental investigation was conducted in order to determine the effect of moisture absorption at different adhesive thickness (i.e., 0.5, 1.0, 1.5 and 2.0 mm) on strength of adhesive T-joint in urea granulator fluidization bed. In particular, T-joint specimens were exposed to three humidity conditions, namely, 80°C, 90°C, and 100°C at a constant time immersion of 15 minutes in water. Stainless steel plate and stainless steel perforated plate were joined by using a specific adhesive jig according to desired thickness. Tensile test was conducted by using universal tensile machine (UTM) at room temperature. The result obtained has enabled to explain the failure mechanisms and characteristics of adhesive T-joint with respect to moisture condition and bonding thickness. Epoxy adhesive with several weight percent of water absorption will degrade the physical properties of the adhesive. Moisture condition has some effect on the strength of the adhesive bonding. 1.0 mm of adhesive thickness provides the highest value of failure load. Experimental results indicated that failure load of adhesive T-joint at room and 90°C water temperature give higher value of strength if compared to water temperature at 80°C and 100°C.

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Models of Adhesive Bonding of Hybrid Structures

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.550.143 ◽

2013 ◽

Vol 550 ◽

pp. 143-155 ◽

Cited By ~ 1

Author(s):

R. Bréthous ◽

V. Nassiet ◽

B. Hassoune-Rhabbour

Keyword(s):

Low Temperature ◽

Adhesive Joint ◽

Adhesive Bonding ◽

Thermomechanical Properties ◽

Diffusion Study ◽

Shear Tests ◽

Stress Zone ◽

Linear Viscoelastic ◽

Adhesive Thickness ◽

Set Up

Adhesives are often based on polymers materials. They are good candidates in order to manufacture adhesives joint because of their thermomechanical properties and their processing which is easier than other materials. Epoxy resins are widely used as adhesives joint. We can meet them in various industrial areas like car, spatial and aerospace domains. Because of numerous combinations between epoxy and amine chemical functions, these joints may be efficient at high or at low temperature. Indeed, close to their glassy transition temperature (Tg), exists an elastic modulus / ductility couple for which, shear stress is optimum: the Optimum Stress Zone (OSZ)[ which is restricted on limited temperatures range. Our study consists in formulating an epoxy amine joint able to be efficient on an extended temperatures rangei.e.a joint able to ensure a stress continuity over a large range of temperatures, for example-50°C to 100°C. To reach this objective, we propose an evolution of the Multi Adhesive Joints (MAJ): an adhesive joint presenting a gradient of mechanical properties. To make this adhesive joint formulation possible, its necessary to control kinetics diffusion at the adhesive scale (200μm to 500μm) between the low temperature adhesive (LTA) and the high temperature adhesive (HTA). The diffusion study will be carried out by using a rheometer. For such adhesive thickness, the rheometer compliance may have an influence on the results. Therefore, this present work proposes to identify and to set up the key parameters, which allow following kinetics diffusion in a rheometer for dimensions similar to those of bonding assembly, by checking the measurements are performed in the linear viscoelastic domain. In a first part, the morphological, mechanical and thermomechanical properties of the nanostructured thermosets versus time are performed. And, the second part will deal with the optimization of the key parameters by performing dynamic shear tests versus time on HTA and LTA samples in sight of kinetics diffusion study.

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Contrasting the Role of Pores on the Stress State Dependent Fracture Behavior of Additively Manufactured Low and High Ductility Metals

Materials ◽

10.3390/ma14133657 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3657

Author(s):

Alexander E. Wilson-Heid ◽

Erik T. Furton ◽

Allison M. Beese

Keyword(s):

Stainless Steel ◽

Stress State ◽

Pore Size ◽

Fracture Behavior ◽

316L Stainless Steel ◽

Equivalent Stress ◽

Failure Behavior ◽

High Ductility ◽

State Dependent ◽

Fracture Models

This study investigates the disparate impact of internal pores on the fracture behavior of two metal alloys fabricated via laser powder bed fusion (L-PBF) additive manufacturing (AM)—316L stainless steel and Ti-6Al-4V. Data from mechanical tests over a range of stress states for dense samples and those with intentionally introduced penny-shaped pores of various diameters were used to contrast the combined impact of pore size and stress state on the fracture behavior of these two materials. The fracture data were used to calibrate and compare multiple fracture models (Mohr-Coulomb, Hosford-Coulomb, and maximum stress criteria), with results compared in equivalent stress (versus stress triaxiality and Lode angle) space, as well as in their conversions to equivalent strain space. For L-PBF 316L, the strain-based fracture models captured the stress state dependent failure behavior up to the largest pore size studied (2400 µm diameter, 16% cross-sectional area of gauge region), while for L-PBF Ti-6Al-4V, the stress-based fracture models better captured the change in failure behavior with pore size up to the largest pore size studied. This difference can be attributed to the relatively high ductility of 316L stainless steel, for which all samples underwent significant plastic deformation prior to failure, contrasted with the relatively low ductility of Ti-6Al-4V, for which, with increasing pore size, the displacement to failure was dominated by elastic deformation.

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