Tensile Shear Strength Characteristics for Adhesively Single-lap Joints Composed of Quasi-isotropic Laminated CFRPs and Aluminum Alloy

Abstract The tensile shear strength of veneer lap joints was characterised. The joints were produced with an Automated Bonding Evaluation System (ABES) using urea-formaldehyde (UF) as well as melamine-urea-formaldehyde (MUF) adhesive formulated for particleboard production. At a fixed heating temperature of 110°C, a systematic increase in bond strength was observed for both adhesives with increasing cure time. The absolute bond strength was significantly higher for MUF compared to UF. Nanoindentation experiments with the same specimens used for ABES revealed a very hard, stiff and brittle character of the UF resin, whereas the MUF proved significantly less hard and stiff, and less brit-tle. Wood cell walls in contact with adhesive, i.e., where adhesive penetration into the cell wall was assumed, showed significantly altered mechanical properties. Such cell walls were harder, stiffer and more brittle than unaffected reference cell walls. These effects were slightly more pronounced for UF than for MUF. Comparing UF and MUF, the micro-mechanical properties of cured adhesive and interphase cell walls confirm earlier observations that tougher adhesives can lead to higher macroscopic bond strength. In strong contrast to that, no obvious correlation was found between micromechanical properties and the strong cure time dependence of macroscopic bond strength.

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Resistance Spot Welding Optimization Based on Artificial Neural Network

International Journal of Manufacturing Engineering ◽

10.1155/2014/154784 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6 ◽

Cited By ~ 5

Author(s):

Thongchai Arunchai ◽

Kawin Sonthipermpoon ◽

Phisut Apichayakul ◽

Kreangsak Tamee

Keyword(s):

Neural Network ◽

Artificial Neural Network ◽

Shear Strength ◽

Aluminum Alloy ◽

Parameter Optimization ◽

Resistance Spot Welding ◽

Spot Welding ◽

Tensile Shear Strength ◽

Tensile Shear ◽

Resistance Spot

Resistance Spot Welding (RSW) is processed by using aluminum alloy used in the automotive industry. The difficulty of RSW parameter setting leads to inconsistent quality between welds. The important RSW parameters are the welding current, electrode force, and welding time. An additional RSW parameter, that is, the electrical resistance of the aluminum alloy, which varies depending on the thickness of the material, is considered to be a necessary parameter. The parameters applied to the RSW process, with aluminum alloy, are sensitive to exact measurement. Parameter prediction by the use of an artificial neural network (ANN) as a tool in finding the parameter optimization was investigated. The ANN was designed and tested for predictive weld quality by using the input and output data in parameters and tensile shear strength of the aluminum alloy, respectively. The results of the tensile shear strength testing and the estimated parameter optimization are applied to the RSW process. The achieved results of the tensile shear strength output were mean squared error (MSE) and accuracy equal to 0.054 and 95%, respectively. This indicates that that the application of the ANN in welding machine control is highly successful in setting the welding parameters.

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Joining Dissimilar Metals between Steel and Aluminum by TIG Welding

Materials Science Forum ◽

10.4028/www.scientific.net/msf.819.45 ◽

2015 ◽

Vol 819 ◽

pp. 45-49 ◽

Cited By ~ 1

Author(s):

Shamsul Baharin Jamaludin ◽

Mohd Zahir Abd Latif ◽

Mohd Noor Mazlee ◽

Kamarudin Hussin

Keyword(s):

Shear Strength ◽

Aluminum Alloy ◽

Microstructural Analysis ◽

Welding Process ◽

Welding Current ◽

Tig Welding ◽

Inert Gas ◽

Dissimilar Metals ◽

Tensile Shear Strength ◽

Tensile Shear

The effect of welding current on the joining of mild steel and aluminum 6063 has been investigated. The joining was carried using a tungsten inert gas (TIG) welding. The welding currents used were 30 A to 80 A. The formation of intermetallic reaction layers (IML) and tensile shear strength of the joining were investigated. The result showed that tensile shear strength increased as welding current increased up to 55 A. Microstructural analysis showed that intermetallic reaction layer was formed at the interface between steel and aluminum alloy during welding process. The thickness of IML was decreased with decreasing welding current.

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