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Showing 1 to 14 of 14 for “"Spot welds"”.
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A fatigue design parameter for spot welds
… carbon and high-strength-low-alloy tensile-shear-spot weldments was investigated using the AT & T Microhmeter. The boundaries between the three stages of the fatigue life were determined based on the resistivity measurements of the Microhmeter. Subsequently, the effects of sheet thickness, …
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A Fatigue Life Prediction Method for Tensile-Shear Spot Welds
… predicts the fatigue resistance of tensile-shear spot welds under constant amplitude loading test. The TSIP model consists of Stage I--fatigue crack initiation and early growth, Stage II--through sheet thickness crack propagation, and Stage III--across sheet width crack propagation. The …
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Life prediction of spot-welds: a fatigue crack growth approach
A life prediction method is developed for spot-welds subject to fatigue loading. Stress intensity factors are used with the Walker equation to develop two crack growth approaches to the problem. The predictions fit data for lap joint configurations well, but not so for peel joint geometries.
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Strength of Arc Spot Welds Made in Single and Multiple Steel Sheets
… was to establish a relationship between arc spot weld shear strength and the arc time used to form the weld. Lap shear tests were performed on both 3/4 in. and 5/8 in. nominal diameter welds. Each weld was formed in one-, two-, or four-layers of sheet steel ranging from 22 gauge (0.028 in.) …
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Fracture path transitions in peels tests of medium carbon steel spot welds
… fracture to a pulled button, in peel tests of spot welds in SAE 1039 steel was evaluated to determine the controlling material properties. Welds were tested in the as welded condition and after tempering at various temperatures to develop a range of hardness and strength in the weld metal. Two …
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Ultrasonic Real-Time Quality Monitoring Of Aluminum Spot Weld Process
The real-time ultrasonic spot weld monitoring system, introduced by our research group, has been designed for the unsupervised quality characterization of the spot welding process. It comprises the ultrasonic transducer (probe) built into one of the welding electrodes and an electronics hardware …
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Acousto-Ultrasonic Evaluation of Cyclic Fatigue of Spot Welded Structures
… explore the damage development in tensile shear spot welds during fatigue loading. There is reasonable data to support the hypothesis that a decrease in an AU signal is indicative of the presence of an internal crack and could be used for monitoring and evaluation purposes.
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A statistical analysis of the fatigue behaviour of single and multi-spot welded joints.
… predictions for the fatigue properties of a spot welded joint based on geometric data. However, the accuracy of these models tends to diminish as the number of spot welds and complexity of the joint increases. This thesis reports on the findings of an investigative study to assess the …
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Spot Friction Welding of Ultra High-Strength Automotive Sheet Steel
<p>Spot friction welding (SFW) was performed on ultra high strength steel (UHSS) steel sheet commonly used in automobile manufacturing. Alloys studied included DP780, DP780EG, DP980, and DF140T sheet steel of varying thickness from 1.2 mm to 1.4 mm. Welding was accomplished using a PCBN standard …
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Fundamentals of friction stir spot welding
… and calls for more attention. Friction Stir Spot Welding (FSSW) is an evolving technique that offers several advantages over conventional joining processes.</p> <p>The fundamentals aspects of FSSW are systematically studied in this dissertation. The effects and influence of process inputs …
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Ultrasonic phased array imaging and data post processing with applications to resistance spot welding
Resistance spot welding is a widely used metal joining method in the automotive industry due to its low cost, ease of automation and high throughput. Resistance spot welding is a process that joins two or more metal sheets through the application of force and high current in a localized region, or …
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Structural modelling of adhesive joints in automotive bodies
… the sheet components in the body shell. Although spot-welding is the predominant joining method for the construction of steel bodies in the automotive industry, other alternatives are now being considered. Adhesive bonding offers the best potential because the uniform load distribution in the …
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Bainitic steel with 30 GPa% characteristics
… with the development is that the steel must be spot-weldable, which means that the carbon concentration needs to be kept low enough to avoid the formation of martensite in the heat-affected zones of resistance spot welds. Fundamental phase transformation theory is used for alloy design, followed …
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A multiscale computational framework for the simulation of local features in large structures
In many engineering applications, it is necessary to account for interactions among multiple spatial scales through numerical simulations. Resolving fine-scale features such as geometrical details, cracks, and localized nonlinearities with high fidelity is crucial for the accurate prediction of the …