A two-dimensional thermal elasto-plastic numerical model is developed by finite element method to analyze and compare the mechanical driving factor for heat affected zone (HAZ) liquation cracking during laser welding and hybrid laser-arc welding techniques. Calculations of transient temperatures and cooling rates are used in conjunction with solidification theory to analyze weld pool characteri...

Lasers are now being used in the automotive industry to produce seam or stitch welds, as alternatives to conventional resistance spot welding, which are used extensively for attaching auto-body panels to subassemblies. The advantages of laser welding over resistance spot welding result from the smallness of the laser spot size, the large penetration depth of the weld into the material and the r...

Laser welding is an advance non-traditional and high energy beam welding technique for dissimilar material, which is being increasingly used in industries like automobile, nuclear reactors, aerospace etc. Again it is a very tough task to joining dissimilar materials due to their properties variation. In this present work two dissimilar metals such as copper and AISI 304 stainless steel are take...

Abridged version: In view of the demands made by the end users in the field of application of vehicle construction for an ever-higher product quality and improved performance, continuous innovations are considered to be absolutely decisive for being successful. This especially applies to the welding technology, and therefore the goal is to develop new, better and more powerful welding processes...

Process monitoring is important for the laser welding system, especially for the weld seam deviation monitoring. A 10kW high power fiber laser butt joint welding of type 304 stainless steel was performed. By combing two different band pass filters, high speed photography was employed to capture the near-infrared images of molten pools. Image difference algorithm was used to obtain the weld seam...

To obtain satisfactory welds in positional laser beam welding, it is necessary to know how process parameters will influence the quality of welds in different welding positions. In this study, the titanium alloy Ti6Al4V sheets were laser welded in two vertical welding positions (vertical up and vertical down), and the appearance, porosity, strength, and ductility of the laser joints were evalua...

Laser beam welding of dissimilar sheet metal combinations such as Ti/Al, SS/Al and Cu/Al are increasingly demanded due to high energy densities with less fusion and heat affected zones. A good weld joint strength involves combinations of dissimilar metals and the formation of solid solution in the weld pool. Many metal pairs suffer from significant intermetallic phase formation during welding w...

Laser beam welding produces good quality welds with minimum shrinkage for sheet metal joints. The quality of welded joint depends upon surface morphology, hardness, mixing of liquid phases and metallurgical non-homogeneity induced by gradients of temperatures and cooling rate at the weld interface. In the present investigation, Titanium Grade5 (Ti) and AA2024 (Al) alloy dissimilar sheet metals ...

Precision components or sensors exposed to corrosive conditions, or required to have extreme performance characteristics, are sealed hermetically into special packages. Epoxy glueing, resistance welding, soldering, electron-beam welding, and laser welding are several of the techniques available for sealing these packages. The disadvantage in the use of epoxies is that they do not create a herme...

In pulsed Nd:YAG laser welding process, the material melts and solidifies consecutively by a peak high power laser beam. The solidification time in this process is very less as compared to that of conventional welding process. The mode of welding process is governed by the process parameters like laser energy, pulse duration, pulse frequency, power and welding speed. This paper aimed at to exam...