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Laser welding is a fusion welding process that utilizes a laser beam as the energy source in order to weld together metals or thermoplastics. It’s known as a high density beam process which can be used to join thick materials with deep and narrow welds.
Laser beam welding can be done without the use of filler metal, although fillers can be used for welding crack prone alloys as well as heat sensitive components. For deeper welds in crack prone aluminum alloys, for example, we have proprietary welding techniques that allow us to weld without the need for filler materials.
The laser’s ability to deeply penetrate into materials results in purer, stronger welds than traditional welding techniques. Not only is laser welding typically stronger than MIG, it’s three to ten times faster, welding relatively thick joints with ease, all without requiring multiple passes or high heat, which can diminish the strength of the welded materials.
The typical defects that can occur in laser welds are solification cracking, the formation of shrinkage cracks during the solidification period of welded metal; porosity, the presence of cavities in the weld metal that form because of the freezing in of released gas from the weld pool as it solidifies; and spatter, droplets of molten material generated near or at the welding arc.
Given the small and precise nature of the laser beam, very small and thin materials can easily be welded together, making it perfect for precision and micro parts welding, medical devices, crack sensitive material welding, as well as any application that requires accuracy, low heat and high weld performance.
Electron beam welding often takes place in a vacuum, since the beam can be scattered by the presence of gas molecules. In doing so, impurities such as oxides and nitrides are eliminated, while impurities in the materials are vaporized. This results in exceptionally clean welds, making it the perfect process for joining a vast range of metal alloys.
Laser welding is capable of making very strong, pure welds. The laser’s focused beam generates less heat than traditional welding processes, which means heat transfer to the part is lessened and its structure is less affected, providing a much higher weld quality with greater tensile and bending strengths.
Electron beam welding is used to make extremely strong joins in metals. Electron beam welds typically retain 95% of the strength of the base material. The welds are also extremely pure because the process usually takes place in a vacuum. Impurities, such as oxides and nitrides are eliminated, and impurities in the materials are simply vaporized. Electron beam welding is an appropriate process for welding difficult to weld materials like titanium, refractory metals, and also hard to weld combinations of materials, like nickel to copper, etc. Electron beam welds can be applied to joints that are physically miniature or huge – the limiting factor is the size of the welder’s vacuum chamber. There are many applications for electron beam welding, including aerospace and defense, energy, automotive and marine. As an example of the versatility of electron beam welding, a spacecraft can have electron beam welded, load bearing structural components, as well as tiny electron beam welded thruster valves and control systems.
Electrons are generated (via an electron gun) and then accelerated to very high speeds using electrical fields. This high speed stream of electrons is then focused using magnetic fields and precisely applied to the materials to be joined. As the electrons impact the materials their kinetic energy is converted to heat, which causes the metals to melt and flow together. Electron beam welding generally occurs in a vacuum as the presence of gas molecules can scatter the beam. The net result is a very strong weld (maintaining up to 95% of the base materials’s strength), that is also dramatically free of impurities.
Electron beam welding is a fusion welding process that uses a beam of high velocity electrons to produce a weld. It can achieve excellent weld depth as well as precise control – from 0.001 inches to 2 inches and more, all the while having very high depth-to-width ratio, allowing for deep and extremely narrow affected zones, thus minimizing material shrinkage and distortion and allowing welds to be made in close proximity to components that are heat sensitive. Electron Beam welds are also very strong and can maintain up to 95% of the strength of the base materials. Because it takes place in a vacuum environment, this type of welding has a high purity level, resulting in extremely clean welds which makes it ideal for joining a wide range of metal alloys. Its versatility makes Electron Beam welding perfect for joining refractory and dissimilar metals which would not be weldable using the conventional welding process. Our CNC controlled welders ensure meticulous control and repeatability at feed rates from 1 to 200 inches per minute.
Electron beam welding generally occurs in a vacuum, and the size of the vacuum chamber can limit the size and amount of parts that can be welded. Further, creating the vacuum in the chamber requires pumping, and depending on the size of the chamber, that can take a long period of time. After the vacuum has been established and the parts welded, the chamber is then brought back to normal pressure, which again adds time to the process. The weld “head” in an electron beam welder is usually fixed, and the parts to be welded have to be maneuvered into position under the beam. Due to the vacuum needed and the physical danger presented by an electron beam – it emits X-rays – an operator cannot be in direct contact with the parts. Hence, parts must be moved remotely, either through manual controls or CNC, during the welding cycle. Depending on the design of the part and the complexity of the welds involved, electron beam welding can range from very expensive to very cost effective. There are no downsides to the quality of an electron beam weld, however.
EB Industry’s electron beam welding service focuses on welding to industry specifications. There are three standards we apply most often to our Electron Beam welding work, all of them originally created specifically for applications where exceptional weld quality is an absolute necessity and weld failure is not an option: AMS 2681 (Welding, Electron Beam), AMS 2680 (Electron Beam Welding for Fatigue Critical Applications) and AWS D17.1 (Specification for Fusion Welding for Aerospace Applications). While AWS standards are excellent for process assurance, EB Industries’ AS9100 certification ensures these standards are consistently applied.
Generally electron beam welders require a physically large, extremely high voltage power supply and a vacuum chamber, which makes the equipment very heavy and basically unmovable. There are partial vacuum electron beam welding machines that do not require a chamber, and there are no vacuum electron beam welders, but the resultant weld does not have the outstanding characteristics of a weld made by an electron beam welding in full vacuum.