Laser: cutting through

January 16, 2015 10:26 am

Lately laser technology has made its way very strongly across many sectors. The laser technique is helping make cutting tool industry more productive, offering reliable results
 Nowadays the cutting tool technology has made valuable advances, especially in the past 10 years which largely is because of newer and newer coating possibilities came into picture. It is observed that the improvisation in overall product is driven by end users’ demand for cutting and machining of harder stiffer alloys of MS and aluminium.
In current scenario, the market requirements are consistently increasing due to environmental and pollution related issues. The issues like reducing the use of lubricant, coolant and also the end users’ never ending demands of cost cutting, reduced cycle times and less maintenance are of highest concern.
Laser technology in cutting tool industryLaser technology is now gaining importance in automobile, fabrication, defence and aerospace, and cutting tool segments. Cutting tool industry uses lasers for both generic and niche processes.
Some laser operations are proving to be very helpful in cutting tool industry. The same are explained by Maulik Patel, Executive Director, Sahajanand Laser Technology Ltd., as follows:• Laser cutting: The flexibility of laser system acts as an important factor to reach the complex geometries even with best quality and at high speed. Laser cutting is now being widely used for pre-processing of the components done with fibre laser cutting which will go for further operation for fine machining or grinding. This saves time and cost for components as well.
• Laser welding: Laser welding processes are much common in industries with high production rate and for those who don’t compromise on quality of welding. Stunning weld quality, fine finish, high-speed, less HAZ and very low thermal distortions are key determinants of laser welding. Laser welding is majorly used on metals namely stainless steel, carbon steel, aluminium and titanium. Bi-metals and alloys as well are preferred to be welded with lasers. Right from microelectronic components to heavy thicker metals, laser welding is versatile enough deliver the best in class results. Bi-metal laser welding of band saw is a budding application.
• Laser marking: Legibility, contrast, permanency, hi-speed operation, very low cost of ownership, flexibility to adapt various marking profiles and contactless process are the key criterion for tooling industry to consider lasers for marking application. Laser marking is used for traceability and branding purpose on carbide tools, drill bits, milling cutters and saw blades. It delivers unmatched performance both in quality and in speed of marking.
• Laser drilling: There are applications of micro machining of some critical components where cutting tool is replaced with laser for drilling or cutting micro holes on critical components for aerospace and defence as well as in medical segment. Highly precise and micron level drilling of fuel injection systems in automobile industry done with lasers is an emerging application.• Other machining processes: Laser operations are now widely used for pre-processing of the components that move towards further operation for fine machining or grinding. In this case, early processing with lasers saves time and cost for components.
“Now laser technology in a cutting tool industry comes up with many inherent advantages. Most laser cutting machines do not need any lubricants for cutting,” points out Naren Shikarkhane, Technical Director, Scantech Laser Pvt. Ltd. “Secondly; harder as well as softer materials are cut at the same speed. In fact harder material such as spring steel gets cut faster than quality MS and with better edge definition.”
The laser as a cutting tool also has taken major steps in its wall plug efficiency making it greener. For example, the wall plug efficiency of cutting lasers has increased from 10 to 30 per cent.
Latest innovations “Lasers are being improved on the aspects of quality of finish and versatility of applications. High speed operation is obviously one of the most important aspects that has been under continuous improvement,” says Mr Patel. “Laser assisted machining is the latest innovation that is catching fast in machine tools industry.”
Laser assisted machining is a process where laser is deployed to pre-heat any component before being cut/drilled by a tool. With this process, the material has fine finish and also the life of tool increases. Since the pre-heating process is already done, there is no need of further heat treatment. It’s not only the economic performance that stands high; but also the quality of machining, repeatability and accuracy achieved through it makes this process effective.
Laser technology contribution Laser technology had just been merely 54 years old but the application and usages had been increasing rapidly due to its versatility for processing. The awareness about various laser systems, their technology and benefits among the Indian manufacturing segment has grown leaps over the course. This awareness has induced them to upgrade their facility with the state-of-the-art laser systems.
“Lasers have predominantly offered highly accurate and quality of machining to various industries including cutting tools,” as Mr Patel puts in, “Economical cost of operation, better productivity and less post processes are the key benefits that any tool manufacturer could enjoy out of using lasers in their production process.”
Optics and coating developments in related field and linear motor technology are becoming affordable now. They also have made a large contribution to further improve the quality and processing speed of laser and CNC for different type of 2D profile cutting. Development in this field has become a great help for automobile body parts.
“On the micro and nano side, laser are now much ahead in surface finishing of engine cylinder by homing operation, which is now strongly competing with traditional machining,” believes Mr Shikarkhane.
In micromachining area, where other traditional cutting tool like ceramic or plastic cannot be used due to their limitations, the laser with ultra short pulses and with high repetition rate, short wavelength are producing miniature sized critical components by cold machining (rapid prototyping).
“We at our level have successfully replaced or conventional tool of cutting by laser in tungsten cutting, replaced punches which were fast wearing out and costly tools by laser cutting,” informs Mr Shikarkhane. “Scantech laser has in its small way directly or indirectly helped to improve the cutting tools or produce a new laser based solutions in its own way as an alternative.”
Increasing use of toughened plastic composites in many body parts: interior and even up to top hats and roofs are being cut slotted or drilled now by laser. This method with its non contact, no tool pressure on component allows end user to reduce product cost.
End noteIt can be clearly seen that today laser is being used increasingly to assist and help cutting tool industry for abrasive coating deposition. Lasers play a vital role in most of the tool manufacturing processes. Right from marking, engraving, cutting, welding, drilling and surface treatment, lasers have substituted the conventional processes due to its quality and efficiency. ————–On the micro and nano side, laser are now much ahead in surface finishing of engine cylinder by homing operation.
Naren Shikarkhane, Technical Director, Scantech Laser Pvt. Ltd.—————
—————Laser assisted machining is the latest innovation that is catching fast in machine tools industry.
Maulik Patel, Executive Director, Sahajanand Laser Technology Ltd.