How Do You Cut Aluminum?
What Laser is Best For Cutting Aluminum?
Why would anyone want to use aluminum? The question really is why would you not want to use aluminum? It has versatility as a strong alloy, but lighter than other metallics. It is ductile and has good thermal qualities. The use of aluminum is so vast and used in so many ways, it has become the material of choice for many. There are numerous grades of aluminum and the three used frequently are: MIC-6, 6061 and 7075. Laser technology is one method being used to manufacture aluminum parts. Experienced services providers, utilize available systems and depending on the project’s requirements process from laser cut aluminum foils, sheets, and plates. By using laser technology they can offer high quality, versatility and repeatability, so when selecting laser technology that best fits your project, the following will be a guide in determining the best fit.
- YAG UV or Ultraviolet laser technology: Best for projects requiring ultra-thin foils.
- Thickness from .0254mm to .254mm thick.
- Great for 2D geometries.
- The kerf of these lasers can be 20um or smaller.
- Allows for finer geometry to be cut with a +/- .0254mm tolerance.
- No vibration to subjected to the material.
- No tooling so design changes made easy.
- Fiber Laser Technology: Best for thicker grades of aluminum.
- Thickness from .254mm up to 40mm or thicker.
- Great for 2D geometries.
- Higher power (wattage) but relatively small beam diameters of 18 to 40um.
- Clean edge cuts and tolerance of +/- .0508mm.
- Heat affected zones controlled by programing.
- CO2 Lasers: Though can cut some thinner foils of aluminum. This type of laser technology is more suited in cutting non-metallic materials like paper, wood, and plastics.
How Do You Cut Aluminum?
If you ever go into a place where industrial or precision parts are manufactured, you will see aluminum being used. It is just a mainstay in products we use every day or in some way improves our lives. First discovered back in 1825, it was not until about 1889 that the process was developed for industrial quantities and usage. As progress was made in manufacturing techniques from the past 100 years or so, so has the need and use of aluminum. It is processed and provided as foils, sheets, blocks, and plates, with numerous grades available. How do you cut this versatile alloy? For hobbyists there are some basic options of using snips and saws. For industries, powered saws like circular and band saws will be sufficient for some applications. Regarding industrial methods, there is not one best choice, but several that stand out and have become the go to for cutting aluminum.
- Yag UV or Ultraviolet laser technology: Best for projects requiring ultra-thin foils.
- Thickness from .0254mm to .254mm thick.
- Great for 2D geometries.
- The kerf of these lasers can be 20um or smaller.
- Allows for finer geometry to be cut with a +/- .0254mm tolerance.
- No vibration to subjected to the material.
- No tooling so design changes made easy.
- Fiber Laser Technology: Best for thicker grades of aluminum.
- Thickness from .254mm up to 40mm or thicker.
- Great for 2D geometries.
- Higher power (wattage) but relatively small beam diameters of 18 to 40um.
- Clean edge cuts and tolerance of +/- .0508mm.
- Heat affected zones controlled by programing.
- CNC Machines can cut from flat plates and blocks of uncut Aluminum.
- CNC Machines include CNC lathes and CNC Vertical mills as well.
- They are controlled by computer generated design files.
- Great for flat and 5-axis parts.
- Tolerances held depend on the geometry and the type of CNC machine:
- For Vertical CNC- can be +/- .0254mm to .508mm.
- Other CNC systems can have tolerance of +/- .127mm.
- Coolant is used to reduce heat affect.
The details for each project will warrant the use of different technologies to cut the aluminum to the desired result. Aluminum is softer compared to other materials like steel or iron, so considerations of surface and edge quality will be topics to review with your service provider.
What is the step by step process to cutting aluminum on a UV laser?
For extremely fine geometries and versatility of design options, using a UV or ultraviolet laser to cut aluminum is a great choice. Though limited to the thickness of the aluminum it can cut, Yag UV laser technology has proven it can cut very high precision of aluminum and other metallic and non-metallic materials. How is this done and what can you expect from this process? The following is a guide the UV laser steps regarding aluminum:
1. Material choice- Aluminum comes in numerous grades and in various raw formats such as foils, sheets, plates, and blocks. For UV laser systems, the materials generally will be in foil or thin sheets, with an upper thickness of .254mm regarding aluminum.
a. Type 6160- a standard or work horse as described by many producing aluminum parts. Has lower cost and about the middle of hardness.
b. 7075- A high grade of aluminum- superior strength and used in critical industry applications for aerospace, defense, sciences. Has comparable strength to steel.
c. MIC-6- Used in applications where consistency in flatness is required and surface finish crucial. Is softer than other grades.
2. The technology of a UV laser is low powered compared to other technologies and works in the range of .1 to 15 watts or so.
3. Handling: Since foil and thin sheets can be damaged easily, procedures are in place to protect uncut material from damage. This is needed throughout the process to ensure complete quality.
4. Importing the CAD or design file: Lasers, like other manufacturing machines, use computer generated CAD files. This is the path the beam will cut.
5. Securing the foil: Using an internal vacuum to secure the foil on the laser bed is best. This keeps the foil flat during the laser process and keeps the beam in focus. A secondary step of securing the foil by applying tape to the materials outside edge can be done.
6. Input of the laser tool: The laser “tool” is a set of parameters used in programing the laser system. This is important because it allows for the fine tuning of the laser to achieve an optimal cut and cost throughput. Some of the settings adjusted are:
a. Laser travel- the rate at which the table or head is moved.
b. The power of the laser- the best wattage for the specific grade of materials.
c. The number of laser passes-often laser work in “passes” or quantity of cycles the laser is programmed to do.
d. Secondary cut passes- some systems use a faster “clean up” cycle to smooth the cut edge.
7. First Article Review: Standard for many service providers is a First Article or F.A. run. This is to check the current laser set-up and tool settings before production runs are started. The F.A. is checked by qualified Quality Control personnel. Resulting in:
a. A QA passing – The job is approved to proceed.
b. A QA rejection- Upon review the part may be out of spec, may need an adjustment to the laser tool and may need to change the material due to damage or the incorrect grade. The F.A. is then run again.
8. Production Run: Once approved the technician or laser operator will run the job to completion.
9. Quality Control: Already having processed an approved F.A., it is the responsibility of the QA inspector to review again the produced parts quality, the review of the order and inspect the level of the contracted order. Possible levels include F.A. and sampling, 100% inspection, AQL level and others.
10. Clean Up and packaging- Completed and approved parts are carefully cleaned (if required) and packaged accordingly to not result in damage during shipment back to the customer.
The overall steps are similar in many industries, but each provider will have their own systems in place to ensure quality and satisfaction.