Microprocessor-based controllers are dedicated to machine tools that allow parts to be created or modified.Programmable digital control activates the machine’s servos and spindle drives and controls various machining operations.See DNC, direct numerical control; NC, numerical control.
That part of the base metal that is not melted during brazing, cutting or welding but whose microstructure and mechanical properties are altered by heat.
The properties of a material show its elastic and inelastic behavior when a force is applied, indicating its suitability for mechanical applications; for example, elastic modulus, tensile strength, elongation, hardness, and fatigue limit.
In 1917, Albert Einstein published the first paper acknowledging the science behind the laser.After decades of research and development, Theodore Maiman demonstrated the first functional laser at the Hughes Research Laboratory in 1960.By 1967, lasers were being used to drill holes and cut metal in diamond dies.The advantages offered by laser power make it commonplace in modern manufacturing.
Lasers are used to cut a variety of materials beyond metal, and laser cutting has become an essential part of the modern sheet metal shop.Before this technology was readily available, most shops relied on shearing and punching to make workpieces out of flat material.
Scissors come in several styles, but all make a single linear cut that requires multiple settings to create a part.Shearing is not an option when curved shapes or holes are required.
Stamping is the preferred operation when shears are not available.Standard punches come in a variety of round and straight shapes, and special shapes can be made when the desired shape is not standard.For complex shapes, a CNC turret punch will be used.The turret is fitted with several different types of punches which, when combined in sequence, can form the desired shape.
Unlike shearing, laser cutters can produce any desired shape in a single setup.Programming a modern laser cutter is only slightly more difficult than using a printer.Laser cutters eliminate the need for specialized tools such as special punches.Eliminating special tooling reduces lead time, inventory, development costs and the risk of obsolete tooling.Laser cutting also eliminates the costs associated with sharpening and replacing punches and maintaining shearer cutting edges.
Unlike shearing and punching, laser cutting is also a non-contact activity.The forces generated during shearing and punching can cause burrs and part deformation, which must be dealt with in a secondary operation.Laser cutting does not apply any force to the raw material, and many times laser-cut parts do not require deburring.
Other flexible thermal cutting methods, such as plasma and flame cutting, are generally less expensive than laser cutters.However, in all thermal cutting operations, there is a heat affected zone or HAZ where the chemical and mechanical properties of the metal change.HAZ can weaken the material and cause problems in other operations, such as welding.Compared to other thermal cutting techniques, the heat affected zone of a laser cut part is small, reducing or eliminating the secondary operations required to process it.
Lasers are not only suitable for cutting, but also for joining.Laser welding has many advantages over more traditional welding processes.
Like cutting, welding also produces HAZ.When welding on critical components, such as those in gas turbines or aerospace components, it is necessary to control their size, shape and properties.Like laser cutting, laser welding has a very small heat-affected zone, which offers distinct advantages over other welding techniques.
The closest competitors to laser welding, tungsten inert gas or TIG welding use tungsten electrodes to create an arc that melts the metal being welded.The extreme conditions around the arc can cause the tungsten to deteriorate over time, resulting in varying weld quality.Laser welding is immune to electrode wear, so weld quality is more consistent and easier to control.Laser welding is the first choice for critical components and difficult-to-weld materials because the process is robust and repeatable.
Industrial uses of lasers are not limited to cutting and welding.Lasers are used to manufacture very small parts with geometric dimensions of only a few microns.Laser ablation is used to remove rust, paint, and other things from the surface of parts and to prepare parts for painting.Marking with a laser is environmentally friendly (no chemicals), fast and permanent.Laser technology is very versatile.
Everything has a price, and lasers are no exception.Industrial laser applications can be very expensive compared to other processes.While not as good as laser cutters, HD plasma cutters can create the same shape and provide clean edges in a smaller HAZ for a fraction of the cost.Getting into laser welding is also more expensive than other automated welding systems.A turnkey laser welding system can easily exceed $1 million.
Like all industries, it can be difficult to attract and retain skilled artisans.Finding qualified TIG welders can be a challenge.Finding a welding engineer with laser experience is also difficult, and finding a qualified laser welder is close to impossible.Developing robust welding operations requires experienced engineers and welders.
Maintenance can also be very expensive.Laser power generation and transmission require complex electronics and optics.Finding someone who can troubleshoot a laser system is not easy.This is not usually a skill that can be found at a local trade school, so service may require a visit by the manufacturer’s technician.OEM technicians are busy and long lead times are a common problem affecting production schedules.
While industrial laser applications can be expensive, the cost of ownership will continue to increase.The number of small, inexpensive desktop laser engravers and do-it-yourself programs for laser cutters shows that the cost of ownership is falling.
Laser power is clean, precise and versatile.Even considering the shortcomings, it’s easy to see why we’ll continue to see new industrial applications.
Post time: Jan-17-2022