View A Video on Laser Cutting- A Quick Introduction
The focused beam of a laser makes it well suited for the energy transfer necessary to cut metal by melting or burning the material along a cut line. Assist gas such as nitrogen or carbon dioxide is used in conjunction with laser cutting to prepare newly cut surfaces for painting or corrosion resistance. An example of the gas assist laser technique is CO2 laser cutting, and it is considered the most powerful wave laser. A laser cutter is often controlled through a precision program combination of CNC and CAD computer systems. CNC systems use CAD designs to input all the necessary machining details into a computer program that then fully directs the laser cutting process, requiring a minimal staff to simply oversee the production and make sure the machines are well maintained. Lasers that are used for cutting may also be used to create patterns and holes in other laser machining and laser micromachining services such as laser drilling and laser welding. Other common laser marking processes include laser etching and laser engraving. Many manufacturers of laser cut products are able to offer custom laser cutting, which is used when the design is too complex or intricate to cut by hand.
Many manufacturing industries, particularly in microtechnology and electronics, depend on laser cutting's microscopic tolerances and precision accuracy to fabricate small, intricate parts. Medical devices use laser cutting to drill catheter holes, hypo-tubes, gas flow orifices and filtering devices, all of which must be perfect since lives depend on them being so. Laser cutting is also used in many manufacturing industries to fabricate precision parts, nozzles, solar cells, gaskets and circuit boards for aerospace and automotive markets. Cell phone parts, computer microchips, transducers and many types of military and communication devices are made with precision laser cut parts. While laser cutters cannot cut through thick metals or create three dimensional shapes in metal plates like water jet cutters can, laser cutters offer tolerances more precise than any other cutting method, with lower edge distortion than most. Many systems we depend upon on a daily basis, such as water piping and refrigeration systems require parts mass manufactured by laser cutting tools.
Using lasers to cut and machine metal has distinct advantages over conventional cutting processes such as thermal machining, mechanical machining, arc welding, EDM and flame cutting. Excellent control of the laser beam with a stable motion system achieves an extreme edge quality. Laser-cut parts have a condition of nearly zero edge deformation, roll-off or edge factor, leaving very little burring on part edges. Laser cutters have higher accuracy rates over any other metal cutting method, with smaller slicing widths and slightly higher precision tolerances than even water jet cutting. Laser cutting is faster than conventional tool-making techniques and has a quicker turnaround for parts regardless of complexity because design changes can be easily accommodated. The use of CNC machining allows for fewer technicians and ensures safety, unlike arc welding, which can be dangerous for the welder and requires individual workers for each piece. Many different kinds of laser cutting services are available, all of which make highly efficient use of materials, creating little waste.
Laser cutting does have a few disadvantages, most of which involve the drawbacks of hot cutting. The material being cut gets very hot, so in narrow areas thermal expansion and warping may be a problem. Distortion and oxidation can be caused by oxygen, which is sometimes used as an assist gas, because it puts stress into the cut edge of some materials; this is typically a problem in dense hole patterns. Lasers also require large amounts of energy, making them more costly to run. Lasers are not very effective on metals such as aluminum and copper alloys due to their ability to reflect light as well as absorb and conduct heat, nor can laser cutting be used on crystal, glass or any other non-metals. Lasers, even low-powered ones, are potentially hazardous to a person's eyesight. The laser beam can focus on an extremely small spot on the retina, causing permanent burn damage in seconds. Infrared and ultraviolet lasers are even more dangerous because the "blink reflex" protects the eyes only if the light can be seen. Although laser cutting and laser cutting services do not offer quite as much cost efficiency as cold water jet cutting, nor do they offer the completely bur-free finished edging of water jet cutting processes, laser cutting is capable of creating tighter accuracies on a smaller scale than any other type of metal cutting process.
Image Provided by Eagle Stainless Tube & Fabrication, Inc.
Laser Cutting Types
- CNC laser cutting is a process that uses an intense laser beam to cut part
shapes out of sheet material. The parts remain flat because the heat
distortion is minimal.
- CO2 laser cutting is a process that uses carbon
dioxide as the main lasing medium. CO2 lasers use a mixture of gases-such as helium
and nitrogen, with CO2 being the most predominant-to create a
cut quality similar to that of milled edges of mild steels and can
operate in continuous wave (CW) or pulses.
- Custom laser cutting is always done with CNC machining programs that are custom programed to design unique designs exactly like the buyer desires.
- is the process of ablating target materials,
typically low vaporization temperature and low thermal conduction materials,
through direct vaporization.
- is a process that uses the noble gas compounds
for lasing. Excimer lasers generate light in ultraviolet to near-ultraviolet
- is a process in which gas is used as the activating
provides cut edges covered
with melted and resolidified metal comprised of the same metal mixture
the material. Thus it has the same resistance to corrosion and is useful
for food processing facilities, chemical plants and sign production.
and all of the processes that cut metal or other materials with lasers to create precision products.
- is the process of creating a hole in material with
a laser beam.
- Laser engraving uses lasers to etch into a surface.
- Laser etching is the process of marking the material without cutting
all the way through using reduced power.
- is the removal of material brought about by laser
material interaction. Laser machining is a term that includes laser
laser cutting, laser grooving, laser marking or laser scribing.
- Laser marking is a process in which material is indelibly marked
at very fast speeds (milliseconds per character). Laser marking is
programmable and environmentally clean.
- Laser metal cutting involves lasers cutting the most common material used to produce machining products: metal.
- Laser micromachining is
a process used to create extreme detail and to cut very precise components
that require close tolerances.
- is the process of using a laser beam to connect two
or more pieces of metal together by melting the areas to be joined
allowing them to resolidify.
- is the process in which large organic dye molecules
are used as the active lasing medium.
- , also known as "fusion," is
the laser cutting process that creates a melt, which a gas jet blows
out of the melt
zone, typically with air. The resultant cut edge is of high quality
but is covered with microscopic ripples.
- is a process in which mirrors are used
to reflect the laser beam to the cutting head while the work piece
material remains fixed.
- is a kind of laser cutting utilizing multiple
axes instead of one. The advantage of multi-axis laser cutting
is the capability of cutting three-dimensional shapes, while the disadvantages
are the higher expense over flat bed cutting, longer set up times
increased safety hazards.
- is a process in which the oxygen does the actual
cutting, and the laser beam maintains the reaction.
- is a cutting process that uses single or train
pulses, as opposed to continuous wave lasers. These pulses
supply greater power at shorter intervals.
- is a process utilizing semiconductor
materials as the active medium.
- is a process in
which the active medium of the laser (typically not semiconductor
lasers) is in a solid state.
Laser Cutting Terms
- A steel alloy
containing a primary iron component minus any other metals necessary to
make stainless steel.
- A device consisting
of a series of hollow tubes and mirrors that supplies the beam in a CO2
- A gas used to facilitate
the cutting process and to blow melted material through the cut area.
Oxygen is usually utilized for cutting ferrous metals, and any inert gas
produces oxide-free cut edges.
- The decrease in
radiation power or energy as the beam is passing through a scattering
or absorbing medium.
- A group of rays that
may be convergent, divergent or parallel.
- The diameter
of a circular beam at a particular point in which the intensity lowers
to a fraction of its maximum value.
- The spread
of the beam angle, expressed in milliradians. One radian equals 3.4 minutes
of arc or nearly 1 mil.
A computer that controls the machine's movement. CNC controls motion tables
or position the work piece beneath the focused laser beam.
- Carbon or mild
steel made with coatings like zinc plating, mill scale, paint, rust or
identification marks. Reduced cutting speeds and more dross on the bottom
of the cutting edge are the result.
- The capability
of a laser beam not to spread significantly (low divergence) with distance.
- An optical device
consisting of two lenses separated by the sum of their focal length that
is used to provide a desired beam diameter to meet beam delivery specifications.
- The continuous-emission
mode of a laser, as opposed to the pulsed operation mode.
that exhibit an extreme reflectivity to laser light and have high thermal
conductivities. These two characteristics lower the cutting speeds and
the highest thickness of material that can be cut.
- A solid crystalline
material with a regular array of atoms utilized as laser sources.
- Also called
"piercing," it is the use of the laser in the pulsed mode
for hole drilling with air or oxygen as the assist gas.
- A characteristic
that determines the size of the material to be cut. Bed sizes are commonly
4' X 8' and some are as big as 5' X 10'.
- A measurement that
is dependent on the properties of the material cut, the lens focal length
and the type of gas in the laser. The width of a cut from a laser will
usually be between 0.1 and 0.4 mm.
- The amount of time
required for the completion of the laser process.
- The operating
span of the focused laser beam calculated as a function of the focal length
of the lens, the wavelength and the diameter of the unfocused beam. A
shorter focal length gives a smaller depth of field.
- Undesirable variations
of either amplitude or frequency of laser output.
- Solidified melt on the
lower edge of the laser cut. Higher amounts of dross result from surface
rust, poor quality steel and incorrect process parameters but can be reduced
by increasing the oxygen pressure and pulsed laser cutting.
- The actual length
of time that the laser beam is cutting, drilling, welding or heat-treating,
as compared to the cycle time.
- A laser
or laser system closed off to prevent hazardous optical radiation from
escaping the enclosure.
- The rate at which
the cutting head moves.
- The position of
maximum energy concentration of a focused laser beam. Focal point is determined
by measuring where the laser beam has the least diameter and the refracted
light rays of a lens conjoin.
- A coaxial assist gas utilized to attain
extreme power levels required for cutting particular metals, usually nitrogen,
oxygen and argon.
- A device that blows
gas into the cutting zone to clear away molten metals or other materials.
At times, the gas reacts chemically with the work piece to create heat
and increase the cutting speed.
small area next to the cut zone that undergoes changes in material properties
as a result of heat conducted into the work piece as it is cut.
- An interference phenomena
captured on a plate or film that can contain large amounts of information
and from which 3D images can be constructed.
- The slit, notch or groove
produced by a laser cutter or the width of such a cut. The kerf is reliant
on the work piece thickness, the properties of the material, the lens
focal length and the kind of cutting gas in the laser.
Kinds of steels particularly manufactured for laser cutting applications.
These steels maintain the strength of standard materials, but with reduced
amounts of impurities like sulphur and silicon, and can be cut to a greater
highest thickness at faster speeds.
- Also called
"laser cavity," it consists of the optical mirrors, pumping
system and active medium. Laser resonators can be stable or unstable based
on whether the oscillating beam converges into the cavity or spreads out
from the cavity
- A legal phrase
indicating a laser or laser system or any other product that integrates
or is intended to integrate a laser or laser system.
- An optic that is either
refractive or reflective and affects the convergence of rays of light
at a point. The depth of focus and power density of a lens can change
with differences in laser beam diameters.
- The temperature
at which a material melts. Materials having high melting points must be
cut more slowly with a laser, since more energy is needed to melt them.
- A method that
creates very short laser pulses by making the phase differences of many
modes or frequencies in the laser cavity fixed (locked).
- Lasers that
provide high-power, short pulses for particular industrial applications.
- Lasers that are like Nd:glass lasers
in that they are both pumped by flashlamp and beam transmissions through
fiber optics, but the ND:YAG laser light can achieve finer detail work.
It is also better than the CO2 laser on highly reflective material.
- A component of the
gas jet in laser cutting that constricts the assist gas and directs it
to a columnar flow.
- Laser output
per unit area, expressed in watts per square centimeter (W/cm2).
- A single, irregular
burst of a laser, in contrast to a continuous beam. True pulses attain
greater peak powers than what a continuous wave output can do.
- The speed
at which pulses are produced, expressed in pulses per second.
- The degree to
which a material reflects laser light. Extremely reflective material such
as aluminum and copper alloys are harder to cut, necessitating lowered
- A sheet of base
material that may or may not have an interconnection pattern.
whose pulse duration time is below one nanosecond.
- The conversion
of a solid or liquid into a vapor. Lasers vaporize the metal or material
they are cutting.
The elimination of material with an industrial laser by evaporation, vaporization