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Emission and weight reduction have been identified over the years by the automobile industries as the most efficient ways to maintain fuel economy and to meet the demand of the government agencies on global warming. These challenges of reducing emission and weight are even being compounded with consumers taste for luxury features which adds to the weight of the traditional vehicle designs. To meet these demands, alloys such are Aluminium Alloys, Magnesium Alloys and Titanium Alloys have been identified as the suitable materials to replace conventional steel structures due to their superior properties such as high strength-to-weight ratio, high tensile strength and high-temperature performance. With the identification of suitable materials to replace the traditional materials, the welding of alloy materials remains a challenge faced by vehicle manufacturers. Although electron beam welding, ultrasonic welding and friction stir welding have proven to give quality weld joints of alloys used in automobile fabrication, their application is limited by the high cost of equipment, need for vacuum environment in electron beam welding, size and shape of base metals. Laser welding with its reduced heat affected zone (HAZ), good seam appearance and deep penetration has widely been applied in an automobile. However, it is not with its own shortcomings such as poor gap bridging capability, difficulty in welding reflective materials and high cost. Arc welding with its low cost compared to other welding techniques and high energy efficiency, therefore, remains a useful welding process in an automobile. In this paper, a review of the various investigations by researchers on MIG and TIG welding of alloys used in the automobile have been documented.

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In powder metallurgy, dry mechanical milling process is an effective technique employed in the reduction of solid materials into the desired size in the fabrication of materials or components from metal powders for various applications. However, the milling operation introduces changes in the size and shape as well as the elemental or chemical composition of the milled substance. These changes introduced after milling requires critical analyses as the performance and efficiency of fabricated components depend so much on the size, shape and chemical composition of the powders. In this data, the effects of vibratory disc milling on the morphological transformation and elemental composition of titanium alloy powder were observed and analyzed by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). The as received titanium alloy powder was subjected to dry mechanical milling machine rated 380V/50Hz at 940 rpm. Milling time of 2, 4, 6, 8 and 10 mins were adopted in this data collection. SEM and EDS analyses revealed that milling transformed the spherical shaped powders into plate-like shapes. This deformation in the shape of the powder increased with increase in milling time. Also, the oxygen content of the powder fluctuated as the milling time increased.

This work examines the influence of disc milling duration on the morphological transformation and crystal reorientation of titanium alloy powder with a particle size below 90 µm. The disc milling time was varied from 2 mins to 10 mins, the morphological features of the powders were characterized through the scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffractometer (XRD). From the results, milling time had a significant effect on the morphology and the orientation of phases in the titanium alloy powder. The SEM images revealed a plate-like shape compared with the un-milled powder with a spheriodal shape. It was also observed that the flattening of the particles increased with milling time. This suggests that the powder is ductile. The oxygen content of the particles increased from 3.4 wt. % before milling to above 10 wt. %. XRD results showed that the milling time did not bring about a new phase and in the position of maximum diffraction intensity, which occurred at 2θ equal to approximately 40.6°. However, there was a decrease in the crystallite size while the lattice strain became higher as milling time increased.