Laser cutting for clean cut edges without post processes
Laser cutting, also known as laser fine cutting or precision laser cutting, describes a thermal cutting process for fast, efficient and precise cutting of almost any type of flat material.
We manufacture individual fineblanked parts according to our customers' specifications. The customer creates a technical drawing according to the desired cutting geometry in a vector-based design program on the computer and provides this as CAD data. This provided data is then sent to the respective laser system and cut out of the individually selected material by a laser beam.
Further processing steps such as forming, soldering or welding can also be used to produce more complex parts in any desired shape and function. For example, if the laser cuts shaped, flat and leaf springs from high-alloy spring steel sheet or strip, these can then be formed as required using bending processes.
Technical details of precision laser cutting
Depending on the laser cutting system, an extremely wide and varied range of materials can be processed with laser fine cutting. It enables tight tolerances, whereby the accuracy is influenced by factors such as heat input and residual stresses. Specific tolerances vary depending on the material, thickness and laser cutting system used.
Further advantages of precision laser cutting at a glance:
- suitable for very different materials
- clean cut edges, hardly any burr formation
- fast, precise and efficient
- flexible processing methods without tool costs
- distortion-free with thin materials without heat input
- high aspect ratios can be achieved with thick materials
- can be partially automated for economical series production
Laser cutting, punching, wire erosion, water jet cutting or etching?
When comparing laser fineblanking, punching, wire EDM, waterjet cutting and etching, various aspects and advantages can be considered. Here is a comparison of the different processes:
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The laser fine cutting
This term covers a range of processes that use lasers to cut different materials.
Advantages:
- All materials can be processed - especially hard, brittle and thin
- Hardly any heat influence
- Hardly any burr formation
- No chipping, so-called flaking of material on the surface
- Cost-effective and energy-efficient
- Can be automated for large quantities
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The Water-jet guided laser cutting
In this relatively new technology, which can still be used in industry, a 50 µm thin, laminar water jet acts as a carrier medium for the laser. This means that the water jet surrounds the laser beam and thus assumes the function of a light guide. The water only guides the laser beam, but does not cut the material. This is done by the laser beam. The distance to the workpiece hardly plays a role due to the precise focusing.
Advantages:
- Greatly reduced heat influence during processing
- Very high processing quality with low cutting edge roughness
- Parallel cutting edges possible up to a material thickness of 20 mm
- Suitable for crack-sensitive materials such as silicon and ceramics
Here, you find out more about water-jet guided laser processing.
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The punching of materials
This is a process in which different materials are processed using a punching press.
Advantages:
- All cold-formable materials can be processed
- Processing of materials in the third dimension
- Combination of different work steps in one process (stamping and bending tools)
- Low costs for large series and repeat series (otherwise high tool costs)
However, the process is not particularly flexible and is therefore particularly suitable for large quantities with identical work steps.
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The Waterjet cutting
In waterjet cutting, materials are cut with water under high pressure. Depending on the hardness of the material, pure, filtered water or a combination with an abrasive such as garnet sand is used.
Advantages:
- All non-water-soluble materials
- Application for high material thicknesses and heat-sensitive materials
- “Cold” cutting process: no heat input into the material during processing
- High edge quality of the components
- No tool costs
The costs for waterjet cutting with abrasive are higher than for pure waterjet cutting. In addition, the abrasive causes faster wear of the jet-guiding components, which in turn also affects the costs.
The process is not suitable for thin materials. Processing brittle and hardened materials can also be problematic. For electronic components where contact with water or moisture is to be avoided, it is advisable to switch to other processing methods or laser technologies.
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The wire erosion
In wire erosion, materials are processed by means of an electrical discharge between the wire and the workpiece. The process originates from the field of spark erosion.
Advantages:
- Extremely high precision thanks to shape accuracy and dimensional accuracy
- Materials with particular hardness can be machined
- Large material thicknesses can also be processed with small cutting widths
However, the choice of possible materials is limited because only electrically conductive material can be machined. Depending on the complexity of the component, machining can result in long processing times and high costs.
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The photochemical etching
In photochemical etching, also known as acid etching or chemical etching, material is removed from the surface of metals using corrosive substances. Here, metal plates are coated with a thin layer of light-sensitive lacquer. This is the pre-treatment for acid etching. The areas that must remain intact are exposed using a stencil or mask. In all unexposed areas, the lacquer is rinsed off and the exposed metal is etched and removed. This creates the desired structure.
Advantages:
- Cost-effective for large quantities
- Processing of complex contours and structures, but only very thin materials
- Very high precision in processing
- Lower tool costs than with stamping technology
- Burr-free and deformation-free process
Disadvantages arise in the selection of materials that can be processed due to their chemical resistance to the etchant. Metals are primarily etched here. The environmental impact is also an important aspect, as some etching agents are harmful to the environment and require separate and safe disposal.
Our three laser cutting processes
Customers from the fields of hybrid and electronics manufacturing (EMS), precision mechanical equipment and apparatus engineering, medical and aerospace technology value our expertise from over 30 years of work experience for laser precision machining. The following three methods are used:
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Laser Fusion Cutting
In this non-contact cutting process, the material - as the name suggests - is melted using a focused laser beam. An inert cutting gas cools the cutting area, shielding the processing point from oxidation and thus preventing an exothermic reaction. This makes it possible for the cutting process to work at a lower feed rate, thus minimizing the thermal load on the workpiece. As a result, metals can be cut with virtually no distortion or stress. The cut edge is smooth, has no oxidation residue (scale) and forms a beautiful edge even without reworking.
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Laser Flame Cutting
Laser flame cutting is mainly used for cutting ferrous materials. A reactive cutting gas, usually oxygen, drives the molten material out of the cutting gap of the laser beam. The laser cutting process is additionally promoted by the process gas. An exothermic reaction occurs. The feed rate is comparatively high and the workpiece is subjected to a significant thermal load at the same time. There is a risk of material burn-off or material distortion and additional post-processing is required to remove the oxidation residues (scale).
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Laser Sublimation Cutting
Laser sublimation cutting is used for thin and sensitive materials. The process enables complicated contours, high precision and high-quality cut edges with very little burr and shallow roughness. The laser beam alone vaporizes the material. This results in an immediate conversion from a solid to a gaseous state, which creates a precise and fine cutting gap by removing material layer by layer. This is a quasi-cold machining process, as the material is removed without or with extremely low heat conduction within the workpiece.
Depending on the application, CO2 gas lasers, solid-state lasers such as fiber and disk lasers or state-of-the-art ultrashort pulse lasers, so-called USP lasers, in the picosecond and femtosecond range are used for processing.
Materials that are processed by laser cutting
Laser fineblanking is a high-precision machining process that can be used to efficiently process a wide range of materials. These include flat materials such as metal sheets made of spring steel sheet, spring steel strip, stainless steel strip and non-ferrous metal strip as well as plastics, which are cut precisely with the precise laser beam. Thin foils, including stainless steel foils and non-ferrous metal foils, can also be precisely processed using the laser cutting process.
In general, the application of laser fine cutting extends to metals and alloys such as stainless steels, non-ferrous, refractory and precious metals, titanium and aluminum.
Even soft and hard magnetic materials such as ferrites and electrical sheets can be precisely cut with the laser beam to meet specific requirements.
Materials with special coatings such as C5 layers or lacquers, such as those found on electrical sheets, are also ideally suited to laser cutting.
Both ceramic substrates and wafers, for example made of aluminum oxide (Al2O3), aluminum nitride (AlN), silicon carbide (SiC), silicon nitride (Si3N4) and silicon, can be adapted to exact specifications using laser fine cutting.
Ultimately, even sensitive materials such as glass and technical ceramics can be gently processed with the fine laser beam.
Products manufactured using laser technology
- Hold-down devices, flat springs, gauges, strips, shims, form springs, leaf springs, contact springs: These can be manufactured from sheet metal using laser fineblanking.
- Lead frames, punched grids, circuit boards: Laser cutting enables precise cut-outs and shapes in electronic components.
- Masks, shadow masks, sputter masks, vapor deposition masks, apertures, stencils, SMD stencils: Precise cuts for these products are important in the electronics and semiconductor industry.
- Shim plates, spacer plates: Laser fine cutting offers an accurate way to produce spacer and shim plates.
- Gauges, spacer foils, compensating foils, solder foils, ceramic foils, shaped ceramics: Precisely cut parts for measuring and compensating purposes.
- Rotors, stators, busbars, contact bridges, flat connectors, battery contacts: Laser cutting enables precise shaping for electrical components.
- Panel or network substrates: high-precision laser-cut substrates for thick-film and thin-film applications.
- Tubes, capillaries, needles: Laser fine cutting can also be applied for precise cuts in cylindrical shapes such as tubes and needles.
- Housings, lids, caps: Precise cut-outs and shapes for housings of electronic devices.
- Grids, screens, metal mesh: Fine cuts for these products are possible with laser fine cutting.
- Watch components, toy components, design articles, jewelry articles: Fine and complex cuts for high-quality products.
