Advances in manufacturing technology and the trends for more precise part geometry have opened the door for new metal-joining applications where traditional TIG and resistance welding methods no longer meet precision, quality, or productivity requirements. Pulsed laser spot welding technology is now being used to replace these processes, often with increased productivity and lower overall cost.
Moreover, the demand for greater precision in high-performance assemblies has favored the use of these lasers as a more cost-effective alternative to the resistance welding that has been used for decades. Fiber laser spot welding eliminates problems associated with resistance welding, including electrode sticking, and cleaning or replacement. Also, since laser welding is a non-contact process, there is no metal deformation of the component parts.
Spot welding is the simplest form of laser welding. There are two types of spot-welding modes: conduction and penetration. The conduction welding mode is employed for micro-joining purposes. Penetration welding permits aspect ratios (ratio of depth to width) much higher than unity.
Laser Spot Welding
Laser spot welding is a non-contact process which uses a laser to create a single weld spot to weld metals together.
Lasers are capable of delivering ac ontinue or a pulse of laserlight with accurate, repeatable energy and duration. When the beam is focused into one place - a small spot - (adjustable anywhere from approximately 0.1 to 50.0 mm in diameter) on the part, the energy density becomes quite large. The light is absorbed by the material causing a "keyhole effect" as the focused beam drills into, vaporizes, and melts some of the metal. As the pulse ends, the liquefied metal around the keyhole flows back in, solidifying and creating a small spot weld. This entire process just a few milliseconds.
Lasers can fire many pulses per second, and, by moving either the work piece or optics, allow either separate "spot" welds or a series of overlapping spot welds to create a laser seam weld that can be structurally sound and/or hermetic.
Considerations for Converting to fiber laser spot welding
Converting from resistance spot welding to laser keyhole welding requires considering several key factors to determine if it’s the right choice for the operation and application.
Cost: Because laser welding is an automated process, it requires an investment in a robotic welding system. For smaller operations that don’t produce a lot of highly repeatable parts, this type of investment may not be feasible or deliver the necessary return on investment (ROI) to justify the purchase.
Tolerance window for material: Proper tooling and fixturing are critical for success in laser welding. The two workpieces to be welded must be pressed together without a gap to create a high-quality laser weld. This makes the right joint and material presentation important, so the operation must be able to support proper setup and part fit-up.
Repetition:Laser keyhole welding is best-suited to a repetitive process in which many parts are produced, even if this means a high mix of parts with lower volumes of each part. Because of the necessary investment in system setup, applications with high repetition or high part volume typically offer the best ROI in laser welding.
Considering these factors can help you determine if laser keyhole welding is right for your operation.
The new Photonweld laser stud welding machines.
Strength that leaves its mark without any mark on the backside
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High-speed stud welding using the Photonweld handheld laser stud-welding machine.
Laser Stud welding
Laser Stud welding, is a form of high efficient and low energy cost welding in which a stud or bolt is permanently connected to the workpiece. The bolt is attached to the workpiece by means of a laser welding gun. This is a welding method where metal pins, bolts, studs, or other small parts are quickly and intensely welded onto a metal surface.
Our advanced Laser stud welding machine, is highly suitable for precision and markless stud welding with diameters from 1.0 to 12.0 mm and lengths up to 50 mm.
With laser stud welding, not only can use be made of bolts, but also small bushings with internal threads. The advantage of the laser stud welding method is the high processing speed, the welder can weld several pieces per minute. There is also almost no heat distortion because the heat is applied very shortly and very locally and the piece cools down quickly. Due to the different methods exisitng, capacitor stud welding and arc stud welding, both types of studwelding can be replaced and thin and thicker material can be welded by laser stud welding.
Laser welding studs
Due to a fast increasing number of enquiries about studs that have to be applied using laser welding, many manufacturer of welding studs started to produce typically laser welding studs. Specific Laser welding studs have been developed in such a way that they are similar in dimension to welding studs for tip ignition. They simply leave off the ignition tip and the slight pitch, so that they can be welded flat on the sheet.
This is a welding method where metal pins, bolts, studs, or other small parts are quickly and intensely welded onto a metal surface.
Our advanced Laser stud welding machine, is highly suitable for precision and markless stud welding with diameters from 1.0 to 6.0 mm and lengths up to 50 mm.