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The Full Name of the Term, “Laser” is a light. light Amplification by Stimulated Emission of radiation. The Basic Elements Of LBM, Light Stimulated emission of Radiation The full form of Laser
A laser beam machining is a non-conventional machining method in which the operation is performed by laser light. of metallic and non-metallic materials. In this process, a laser beam of high energy is made to strike the workpiece, and the thermal energy of the laser gets transferred to the surface of the w/p (workpiece). The heat so produced at the surface heats melts and vaporizes the materials from the w/p. Light amplification by stimulated emission of radiation is called LASER.
What Is Laser Beam Machining
Light amplification is the key element for producing lasers. The light amplification is a result of stimulated emission due to incident photons of high energy.
There are three main components to any laser system: laser medium means for exciting the laser medium to the state of excitation which is the source of energy, and the optical feedback system. Some other provisions such as a cooling system for the mirrors, a guiding system for guiding the laser beam, etc., are also equally important.
The laser medium can be liquid such as die; solid for instance neodymium-doped yttrium-aluminum-garnet; gas such as CO2, Ne. Laser light is different from ordinary light in the manner that it is highly directional, has better focusing characteristics, and has high power density.
These different and unique aspects of laser light make it suitable for the processing of materials. The most commonly used lasers for laser beam machining (LBM) applications are Nd-YAG and CO2 lasers. The wavelength of CO2 lasers in the infrared region is 10 lm. The CO2 laser possesses better efficiency, high beam power, and good quality.
The Basic Elements Of Laser Beam machining (LBM)
- Laser Rod or Tube (Which is Made Of Glass Coated with reflecting material)
- A flash lamp (which is the source of energy)
- A pair of mirrors (One at each end of the tube)
- An Amplifying Source
- A source of power supply (A.C or D.C)
- A Cooling System
- A lens (which is the Focusing Source)
Working Principle of Laser Beam Machining (LBM):
The material removal mechanism in the LBM (laser beam machining) technique can be categorized into different stages: melting, vaporization, and chemical degradation. The high-energy laser beam is absorbed by the workpiece surface in the form of thermal energy. This high thermal energy transforms the volume of the workpiece material into a molten, vaporized, or chemically changed state. The high-pressure gas then assists in removing the molten or vaporized material.
The physics of the LBM is pretty complex owing to losses taking place at the workpiece material in the form of reflection and scattering. The process progresses
LBM is used to perform various types of drilling, slitting, slotting, scribing, and marking operations. Drilling small diameter holes is possible—down to 0.025 mm (0.001 in). For larger holes, above 0.50-mm (0.020-in) in diameter, the laser beam is controlled to cut the outline of the hole. LBM is not considered a mass production process, and it is generally used on thin stock. The range of work materials that can be machined by LBM is virtually unlimited. Ideal properties of a material for LBM
Laser Beam Machining Process Video
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Main Parts or Construction of Laser Beam Machining:
A high voltage is required to supply the power to the laser or to provide the system energy to donate electrons to the post.
It is used in the workplace to illuminate the white light at a very fast speed and produce intense construction so this flashlamp is used.
We usually know the function of the capacitor, the capacity is to store or filter 4 of the circuit, its capacitor in a word means container because the capacitor stores the current for a while and makes it more powerful and active, this is the main function of the capacitor.
So here the capacitor is used during the flushing process.
The general function of lenses is to make small objects easier to see or see clearly.
In this case, the lens is used to see our work price clearly and to see the small size in a big way for the convenience of work.
The workpiece is where our work is usually done. Means suppose an object or a metal is placed in a machine in which a drill or any machining will take place. In that case, we call that object a workpiece.
Application of Laser Beam Machining:
- The laser beam machining process is used for making very small holes.
- Mass macro machining production.
- LBM is used in surgery. In the medical industry, it is used for hair removal and cosmetic surgery. Photography in medical science. Spectroscopic Science.
- In the electronics industry, it is used for circuiting and wire stripping (for connecting the two ends).
- Selective heat treating of materials. Laser beam machining is mostly used in the automobile, aerospace, shipbuilding, electronics, steel, and medical industries for precision machining complex parts.
- Complicated welding of non-conductive and refractory materials.
- Micro-drilling operation. In light manufacturing industries, it is used for engravings and drilling other metals.
Advantages of Laser Beam Machining:
- Any material can be machined, including non-metals.
- The creation rate is high.
- There is no immediate association between the device and the work.
- No apparatus wear.
- And most items do not require additional finishing; They can be combined with gases that help make the cutting process more efficient.
- This helps reduce oxidation of the W / P surface and keeps it free of melting of the vaporized material.
- It has the ability to engrave or cut almost all types of material. But it is best suited for brittle materials with low conductivity.
- There is no mechanical power on the work.
- The intensity impacted zone is tiny.
- Heat-treated and attractive materials can be welded without losing their properties.
- Delicate materials like elastic, and plastic can be machined.
- Tiny openings can be machined.
Laser Beam Machining Disadvantage:
- The overall efficiency of the laser machine is very low and it is not possible to operate large amounts of metal with it.
- The production rate is very low and requires a highly trained workforce to handle laser beam machining.
- The machining process requires a lot of energy. It is not easy to produce deep cuts with w / p that have high melting points and usually cause a cone.
- Flash lamp life is short and it is a high-cost complete operation.
- It is limited to operation on a thin seat also it is not capable of deep holes.
- The machined holes are not round and straight.