Product category:
Metals foundry, materials and equipment
News Release from: Trumpf | Subject: Direct Laser Forming
Edited by the Manufacturingtalk Editorial
Team on 24 June 2004
Direct laser forming fuses pure metal
powders
Unlike laser sintering, direct laser forming fuses pure metal powder in a shielding gas atmosphere and does not use binders or fluxing agents to produce a non-ferrous part.
What is already considered normal for plastics, is still uncharted territory in the world of metals Case in point: generative laser processes employed in the manufacture of components for serial production
This article was originally published on Manufacturingtalk on 21 Jun 2001 at 8.00am (UK)
Related stories
Heavy duty laser profiler works through the night
Palletisation and latest control and diagnostics systems enable laser profiling system to cut dumper truck parts under 'lights out' conditions.
Two laser heads are three times better than one
In theory a twin-head laser profiler produces double the output of a 'normal' single-head machine.
Except in this case, it is around three times as productive!
Trumpf's Direct Laser Forming combines the well-known advantages of generative methods with serial production materials.
And the perfect platform to support this method is the TrumaForm LF with its accompanying programming environment.
In a fashion similar to other generative "powder bed" methods, components with complex shapes are built up layer by layer from a 3D CAD model.
Further reading
Trumabend brings accurate, consistent bends
The biggest benefits to come from the TrumaBend pressbrake to date have been its accuracy and consistency of bend, said Operations Director Tony Yapp at road sweeper manufacturer, Johnston.
Trumpf to show fastest CNC punching machine
Trumpf will be holding their annual In Tech 2001 Open House event at their premises in Luton on 14th, 15th, 16th, 19th, 20th and 21st March.
Laser and punch boost switchgear output
The bottom line at Lucy Switchgear is that one laser and one punch have enabled the company to produce 10,000 parts/week, compared with some 6,000 parts/week from the old two-punch facility.
However, in contrast to methods like laser sintering, Direct Laser Forming uses pure metal powder without any binding or flux agents whatsoever.
Since the laser beam completely fuses this powder in an shield gas atmosphere, the result is a practically non-porous component with material characteristics that equal those of the original material.
This method can be used not only in serial production of injection molds with integrated cooling channels, but can also be applied in the rapid manufacture of single parts and small batches for ultra-light construction or in medical technology.
"We fully intend to explore this broad range of possibilities, " says Dr Joachim Hutfless, Director of New Processes at Trumpf Werkzeugmaschinen, who is in charge of the machine's engineering.
Complex injection molds, for example those with internal cooling channels, are traditionally produced in multi-step methods.
"Needless to say, the quality of the finished component is excellent, but production is very time consuming.
By integrating Direct Laser Forming into the process chain, the overall fabrication time for a tool can be drastically reduced," says Dr Hutfless.
This method creates a tool blank directly from a 3D CAD model in one step.
Typical production times are measured in terms of hours or, in the case of larger volumes, one or two days.
The blank can then undergo immediate final machining.
Downtimes due to transfer or waiting periods are consequently eliminated from the overall process.
Instead of weeks, the desired tool in serial parts quality is ready within days.
Two examples of the kind of performance that this machine is currently capable of achieving involve the materials stainless steel 1.4404 and tool steel 1.2343.
Here, surface roughness is measured in terms of a few tenths of a millimeter while hardness values equal those of the base material.
The metal structures produced are practically free of pores - an essential factor in the final machining of components, whether it is milling, eroding or polishing.
The TrumaForm LF - a true production machine - when designing the machine, Trumpf placed special emphasis on flexibility and productivity as well as on work and process safety.
The real heart of the machine consists of two identical process chambers where the actual build-up takes place.
While the parts produced in the one chamber are cooling off, the other chamber can begin work on the next job - and with a change of material if required.
Automated overnight or weekend production is therefore possible.
And in terms of construction and cooling times, this is a definite time saver.
A moveable sliding carriage conveys the laser beam's lens system to the currently active process chamber, and a mirror-scanner positions the laser beam above the workpiece.
The work platform can also be heated so that even materials that are hard to weld can be effectively machined.
The part can therefore be tempered during production while distortion and cracking potential are minimized.
To accommodate various component geometries, the TRUMPF programming system offers a variety of processing strategies that support the user in the production of different complex parts.
Programming is simple but does require a basic understanding of technology.
The new Trumpf HLD 251 Disc Laser serves as the laser beam source.
"Based on its excellent beam quality, the HLD 251 is a perfect, nimble tool for Direct Laser Forming," says Dr Hutfless.
A fiber-optic cable with a core diameter of 100 micron guides the laser beam to the machine.
With a maximum laser output of 250W, the HLD 251 has enough power in reserve to machine even highly reflective materials like aluminum.
For customers that want to use the laser for multiple applications, Trumpf offers a laser network.
Remote diagnostic functions and integrated powder handling ensure process and work safety on the TrumaForm LF.
Remote system diagnostics is useful not only for service purposes but also for collective solutions to process engineering problems.
For this reason, sensors monitor all important system functions.
Thanks to the powder handling feature that is integrated in the machine, the operator has almost no contact with the metal powder itself.
The material enters the powder reservoir by means of a slide gate.
Once machining is completed, an integrated suction device automatically removes any excess powder, and any remaining powder clinging to the component can then be vacuumed by hand.
The powder is collected in a container and can be re-used after cleaning.
The basic concept of the TrumaForm LF offers a wide range of possibilities for improvements in process engineering that by no means have been exhausted.
Today's focus is on steel materials, but additional materials will be added in the future.
TRUMPF also offers its customers comprehensive support for the machine.
We can even extend this close collaboration to customized applications.
Functional or individual components made from serial production material - when conventional production methods (if at all) are able to manufacture complex components rapidly in the original material, they often do so only at great expense.
Direct Laser Forming, on the other hand, has its greatest potential in this very area.
"It will definitely come to be seen as a technology that is less of a substitute and more of a complement in new process chains," explains Dr Hutfless.
Beyond tool and mold making, additional uses are possible in the "rapid manufacturing" of functional prototypes having identical serial characteristics (e.g hollow structures for ultra-light construction from aluminum) and in the manufacture of individual components in medical technology (e.g implants, dentures made of titanium).
The ability of Direct Laser Forming to process these materials has already been proven. Request a free brochure from Trumpf ...
• Trumpf: contact details and other news
• Email this article to a colleague
• Register for the free Manufacturingtalk email newsletter
• Manufacturingtalk Home Page
Search the Pro-Talk network of sites
