consequence of metal vaporisation in keyhole welding conditions lower thermal

Consequence of metal vaporisation in keyhole welding

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consequence of metal vaporisation in keyhole welding conditions, lower thermal distortion of the weld assemblies, higher welding speeds, narrower HAZ and better productivity are obtained compared to conventional welding process. 2014 Starke et al. also make a research/review on the new joining trends. Friction stir welding offers many advantages over other solid-state welding processes, including little distortion, little if any weld shrinkage and a significant reduction in consumable costs. the paper pointed out that friction stir welding is approximately 10 times faster than manual riveting and provides a continuous joint for improved structural rigidity. Laser-beam welding can be used to join all of the light metals. The technology for welding of aircraft structures was pioneered by Airbus. Laser-beam welding is used for joining large metal fuselage parts with stringers, such as those in the Airbus A380. Laser-beam welding is much faster, it is six meters per minute than the speed of riveting and has many advantages even though it requires a greater amount of inspection. In addition, the elimination of the rivets makes the structure less susceptible to corrosion. 2016 Xi et al. has a different approach in joining process, His paper introduced robotics in the riveting process. Xi et al. called the system the "Robotic Percussive Riveting System". His paper pointed out that riveting is still the widely acceptable process in joining metal parts because riveting method generates no thermal deformation. Aluminum alloys are high high thermal conductive materials and welding can compromise its microstructural properties. This robot will make riveting automatic. Riveting requires drilling a hole first and then inserting a rivet for fastening. Two riveting processes are exercised in practice, simultaneous and sequential. The first one is to drill and rivet together on a rivet spot, which demands a large tooling to combine a drill and a rivet gun. This process is typically applied on large automated riveting machines where tool accessibility is not of concern for the assembly of large and flat panels. The second process is to drill a series of holes first at the required rivet spots and then switch to a rivet gun for riveting. the required rivet spots are determined by rivet patterns in light of industry standards. For automation, there are two ways to obtain the coordinates of these spots. The first one is to extract from CAD models, as modern aircraft components are designed using CAD. The second way is to compute these spots directly according to rivet patterns like rivet pitch, edging, and rivet spacing. Ma et al. focuses his paper on the effects of friction stir welding on the grains and microstructure of aluminum alloys. FSP has been proven to be an effective and versatile metalworking technique for generating fine-grained microstructures. Severe plasric deformation is a generic term describing any metalworking techniques imparting a complex stress state, high strain typically
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