To the Editor: W elders are at risk of a wide range of respiratory health problems, including bronchitis, airway irritation, and lung function changes.1–5 Despite short duration of exposure, an inception cohort study of apprentice welders in Quebec documented a significant respiratory function decline, incidence of welding-related respiratory symptoms suggestive of occupational asthma and sensi...

Electron beam welding has shown a remarkable job in the space industry for welding of components. It is performed under a vacuum environment that eliminates foreign matter such as hydrogen, oxygen, and other gases. Joining of similar and dissimilar materials is the main advantage of electron beam welding with high depth to width ratio as well as sharp focus at the point where parts are to be we...

The factors that have an impact upon fatigue strength are residual stress, stress concentration, the mechanical properties of the material, and the macrostructure and microstructure. Residual stress is one of the most important factors but its effect on high-cycle fatigue is of more concern than the other factors. Residual stress is a tension or compression that exists in a material without any...

A liquation cracking mechanism of dissimilar Al alloys during the friction stir welding (FSW) is suggested in this study. To identify the mechanism, the precipitates were analyzed and Al-Mg-Cu phase diagrams were calculated. Electron backscattering diffraction (EBSD) analysis and electron probe microanalysis (EPMA) were also conducted. In the same manner as constitutional liquation, at high hea...

This work aims at investigating the spot weldability of a new advanced Quenching and Partitioning (Q&P) steel and a Transformation Induced Plasticity (TRIP) steel for automotive applications by evaluating the effects of the main welding parameters on the mechanical performance of their dissimilar spot welds. The welding current, the electrode tip voltage and the electrical resistance of sheet s...

In manufacturing lithium-ion battery packs for electrical vehicles such as the Chevy Volt, it is critical to create reliable interconnections between battery cells, module-to-module, and module-to-control unit. Such joint connections must possess reliable electrical conductivity and sufficient mechanical strength to ensure battery performance. Ultrasonic metal welding has been adopted for batte...