The History of Laser Cutting
The History of Laser Cutting
Laser Cutting: A Popular Process Across Diverse Industries
Laser cutting has evolved into a highly sought-after method in various industrial sectors, including engineering, architecture, the medical field, marine applications, and construction. Although the cutting-edge machinery and technological advancements associated with laser cutting lend it a contemporary feel, its origins trace back to the mid-20th century. This article delves into the historical development of laser cutting and the rise of fibre lasers as some of the world's most efficient and precise tools.
The Beginnings of Laser Cutting Technology
Contrary to popular belief, laser cutting is not merely a modern invention. The technology behind lasers actually celebrated its 60th birthday recently! The initial pulsed laser prototype emerged in 1960, when Theodore Maiman successfully activated the first laser on May 16, at the Hughes Research Laboratory in California. This breakthrough involved shining a high-intensity flash lamp onto a ruby rod with a silver-coated exterior.
In 1964, Kumar Patel at Bell Labs revolutionized the industry with the creation of the carbon dioxide laser, which was the most powerful continuously operating laser of that era. The introduction of this laser technology sparked significant excitement and concern among scientists and the public alike. Some media outlets depicted lasers as "death rays," leading to trepidation about this innovative technology. The anxiety regarding lasers was humorously highlighted in the iconic Bond film "Goldfinger," where a villain almost cut Sean Connery in half using a powerful gold laser.
When Did Lasers Enter Production?
The first continuous-operation gas laser emerged in the late 1960s. Notably, Peter Houldcroft from Cambridge utilized an oxygen assist gas to effectively slice through 1mm thick steel sheets using a focused CO2 laser beam. It became evident that combining a focused laser beam with an oxygen assist could significantly enhance precision and speed in the cutting process.
Western Electric debuted the first laser designed for production purposes in 1965, primarily used to cut holes in diamond dies. In August 1970, Boeing conducted research on CO2 laser cutting techniques for hard materials, concluding that laser technology was both an effective and cost-efficient tool for cutting.
The early 1970s marked a period of robust advancement in oxygen laser cutting, enabling the cutting of various materials, including metal, which had been beyond the capabilities of carbon dioxide lasers earlier.
By the mid-1970s, Western Electric was quickly ramping up production of laser cutting machines.
The Emergence of Fibre Lasers
Laser cutting technology is dominated by two major types: carbon dioxide and fibre lasers. While CO2 lasers are known for their cost-effectiveness, fibre laser cutting boasts superior efficiency and greater precision, along with reduced energy consumption during operations.
Although fibre lasers were first conceptualized in 1963 by Elias Snitzer, it took two decades before the commercial introduction of these devices in the late 1980s. The late 1990s saw considerable advancements in laser cutting technology, with an increase in the availability of high-power lasers capable of cutting large volumes.
The pioneering fibre lasers suitable for cutting reflective metals made their debut in the early 2000s, enabling the cutting of materials such as aluminium and brass.
Innovations in Laser Cutting Technology: The Bystronic Bystar
The Bystronic ByStar Fiber 12kW represents a significant advancement in fibre laser cutting technology, capable of effortlessly slicing through even the thickest metals. This high-performance laser cutter specializes in handling large batches and high-volume jobs, managing both thick and thin sheets of various materials, including mild steel, stainless steel, and aluminium, up to a thickness of 30mm with remarkable speed and efficiency.
Exclusive Laser Cutting Services for Your Next Project
At Laser 24, we offer laser cutting solutions for a wide array of metals. Our zero-handling process ensures that you receive the cleanest cuts without manual handling damage. Our completely automated process allows us to control cutting conditions, delivering the highest quality parts for your projects. Coupled with our press braking and finishing services, we can efficiently bend, grain, and de-burr metals.
Our expertise extends across numerous sectors, including marine, medical, and engineering laser cutting projects. Our commitment to investing in top-tier machinery allows us to provide exceptional quality parts at competitive prices, reinforcing our position as a leading laser cutting company in the UK.
For more details on our services across Essex, Kent, London, and nearby areas, or to discover how we can assist you with your forthcoming project, don't hesitate to reach out to our team at 733 883 or [protected] today.
Understanding Laser Cutting Technology
Laser cutting is a process that uses lasers to vaporize materials, producing an edge that is precise and clean. While predominantly utilized in industrial manufacturing, laser cutting is also embraced by educational institutions, small businesses, architectural firms, and hobbyists. The mechanism directs the output of a high-powered laser, primarily through an optical system. The technology integrates laser optics along with CNC (computer numerical control) to accurately orient the laser beam on the target material. Commercial laser cutting equipment operates using a motion control system to execute cuts based on a CNC or G-code pattern. The concentrated laser beam interacts with the material, either melting, burning, vaporizing, or blowing it away with a gas jet, ultimately creating a high-quality surface finish on the cut edge.
The Development of Laser Cutting Technology
In 1965, the first laser cutting machine was employed to drill holes in diamond dies, courtesy of the Western Electric Engineering Research Center. In 1972, British innovators advanced laser-assisted oxygen cutting techniques for metals. By the early 1970s, this technology found applications in cutting titanium for aerospace use, while CO2 lasers were adapted to cut materials like textiles—then considered less thermally conductive than metals.
The Laser Cutting Process
The laser beam is focused onto a work zone using a high-quality lens, with the beam quality directly influencing the size of the focused spot. Typically, this focused area may measure less than 0.32 mm in diameter. Depending on the material's thickness, kerf widths as narrow as 0.10 mm can be attained. For cutting initiation from non-edge areas, a piercing process is necessary prior to executing cuts, utilizing a high-power pulsed laser to create holes in the material.
At the focal area, the laser produces intense parallel rays of coherent light, measuring between 1.5 and 2.0 mm in diameter. Focused and intensified using a lens or mirror, the beam can create a tiny spot of approximately 0.025 mm in diameter, resulting in a highly intense laser beam. To achieve an even surface finish during contour cutting, it is essential to rotate the beam polarization while transitioning around the workpiece's perimeter. For sheet metal applications, focal lengths typically range between 38 and 76 mm.
Comparative advantages of laser cutting over traditional mechanical cutting include simplified work holding and reduced contamination risks, as there are no cutting edges that might accumulate debris. Moreover, lasers allow for greater precision, as the beam does not wear over time. Additionally, there is a minimized likelihood of warping the material, owing to the small heat-affected zone associated with laser cutting.
Compared to plasma cutting, laser cutting for metals offers superior precision and lower energy consumption; however, traditional industrial lasers may struggle to cut through thicker metals that plasma cutting machines can tackle. Yet, newer laser models with higher power ratings are making strides, nearing the cutting capabilities of plasma systems, albeit at higher initial costs.
Different Types of Laser Cutting Machines
There are three principal laser types utilized in cutting applications: CO2 lasers, neodymium (Nd), and neodymium yttrium-aluminium-garnet (Nd:YAG) lasers. CO2 lasers are versatile for cutting, boring, and engraving tasks, while Nd and Nd:YAG lasers cater to specialized applications requiring high power.
CO2 lasers typically harness energy by pumping gases through a current (DC-excited) or radio frequency (RF-excited) methods, with RF methods becoming significantly more favored recently due to their efficiency. CO2 lasers tackle a diverse array of materials, including titanium and various types of wood, while YAG lasers concentrate on metals and ceramics.
Laser Cutting Methods Explained
Multiple techniques are available for laser cutting, each well-suited for specific materials. Notable methods include vaporization cutting, melt and blow, thermal stress cracking, scribing, cold cutting, and reactive cutting.
Understanding Vaporization Cutting
Vaporization cutting involves using a focused beam to heat the material’s surface until it reaches a flashpoint, generating a keyhole effect. This process leads to increased absorptivity, which deepens the hole as the material bores and vaporizes.
Melt and Blow Method for Efficient Cutting
The melt and blow technique employs high-pressure gas to eject molten material from the cutting area, reducing energy requirements. Initially, the material is heated until melting, then a gas jet expels the melted portion from the kerf.
Utilizing Thermal Stress Cracking
Brittle materials are particularly susceptible to thermal stress cracking, wherein a laser beam is focused to induce localized heating, resulting in cracks that can be steered by movement of the beam. This method is commonly adopted for glass cutting.
Stealth Dicing in Semiconductor Fabrication
For microelectronic chips, a stealth dicing process is performed utilizing an Nd:YAG laser, effectively separating chips from silicon wafers.
Reactive Cutting Techniques
Also known as "burning stabilized laser gas cutting," reactive cutting employs a laser beam to ignite combustion for cutting carbon steel, achieving good results on thicker steel plates with comparatively lower laser power.
Precision Tolerances and Surface Finish
Laser cutting systems can achieve positioning accuracy within 10 micrometers and repeatability within 5 micrometers. Standard roughness typically escalates with increased sheet thickness but diminishes with higher laser power and cutting speeds. When cutting low carbon steel at an 800 W laser power, roughness values vary significantly based on material thickness.
Configurations of Laser Cutting Machines
Industrial laser cutting machines are primarily categorized into three configurations: moving material, hybrid, and flying optics systems. These configurations influence how the laser beam interacts with the material during the cutting process. The X and Y axes denote the cutting head's motion, while the Z-axis controls the laser head.
Implementing Pulsed Lasers
Pulsed lasers deliver brief bursts of energy, ideal for piercing or creating small holes, particularly under low cut speeds. Most industrial lasers can toggle between pulsed and continuous wave formats under numerical control.
Power Consumption in Laser Cutting
One of the main drawbacks of laser cutting is its considerable power consumption, with efficiency ratings ranging from 5% to 45%. The specific power required for laser cutting varies based on material type, thickness, and other operational parameters.
Production and Cutting Speed
Production rates in laser cutting are confined by factors such as laser power, material thickness, and properties. Common systems (1 kW) can efficiently cut carbon steel up to 13 mm thick, often outperforming standard sawing by as much as thirtyfold.
See Also
References
Bibliography
For further inquiries about our Industrial Laser Cutter, feel free to reach out to us.