Laser sintering produces tooling inserts

Among plastics and metals powders introduced by EOS for laser sintering, a martensite-hardening steel of high strength and toughness can be used to produce heavy-duty tooling inserts.

EOS introduced more metals and plastics powders at the UK’s MACH 2008 machine tool exhibition last week The introductions will extend the applications of additive layer manufacturing applications in rapid manufacturing and prototyping, said EOS

Laser sintering produces tooling inserts – EOS MaragingSteel MS1 is a martensite-hardening steel of high strength and toughness, and which can produce heavy-duty tooling inserts.

EOS said the laser sintered product can equal or be even superior to, conventional tool steels.

Other applications include making batc hes of high-performance parts for the aerospace industry.

The MaragingSteel MS1 material’s composition corresponds to US classification 18 maraging 300, European 1.2709 and German X3NiCoMoTi 18-9-5.

EOS told manufacturingtalk that it is easily machinable after the laser building process.

It has a tensile strength of 1,950MPa and can be post-hardened, using simple thermal age-hardening, to approximately 55 HRC.

Vice president at EOS, Dr Michael Shellabear, said: "MaragingSteel MS1 is one of the reasons that our metal technology is currently booming.

Sales of EOSINT M systems have increased over the last three years by an average of 43% annually".

He continued: "There have been other drivers as well, for example our new titanium TiAl6V4.

Various manufacturers in the medical device industry are testing and qualifying the material.

It also has the significant advantage of helping to decrease weight in the aerospace industry, reducing fuel consumption and CO2 emissions".

* Plastics powders – PrimePart DC is an impact resistant plastic material from EOS.

The natural coloured polyamide offers a fracture elongation of 50%, which is about double that of previously available materials.

It has a tensile strength of 48MPa and a Young’s modulus of 1,550Mpa.

Other mechanical properties are comparable to those of the proven PA 2200 polyamide, said EOS.

Vice president for plastic laser-sintering at EOS, Thomas Mattes, said: "We are seeing a lot of interest from the automotive industry for applications that require good impact performance, such as interior parts".

Another recent powder is PrimePart ST, a flexible material with a 250% fracture elongation.

Parts laser-sintered from this material are fully dense, said EOS, so gas-tight products can be produced directly.

Compared with other flexible laser-sintering materials available, PrimePart ST shows a four times higher tensile strength of 8MPa.

EOS said it is the first flexible material for layer manufacturing that does not require post-infiltration.

Potential applications are shoe soles, seals and hoses.

In future, EOS will offer a wider choice of polyamide colours.

PA 2202 black is a polyamide material containing black pigments, the resulting parts being coloured throughout their whole volume, which makes them resistant to scratches, abrasion and dirt.

The parts are thus well suited to mechanically stressed applications or dirty environments, such as under vehicle bonnets.

PA 2203 grey is a further alternative in light grey.

* Laser-sintering machines – the machines that make these parts were not shown at MACH 2008, but the latest model for metals powder sintering is the EOSINT M 270,.

The machine uses a 200W Yb fibre laser, which can be focussed to 100 micron diameter, allowing the production of very fine detail resolution on the part surface.

The machine also has an innovative dual-focus feature that automatically switches between different laser spot sizes during laser-sintering to optimally combine detail accuracy and build speed.

EOS said that its EOSINT M 270 has been sold successfully in the UK market since its introduction, notably into the aerospace, motorsport, medical and academic sectors.

The EOSINT P 730 is a plastics laser-sintering machine based on the EOSINT P 700, said by EOS to be the only twin-laser system on the market.

The EOSINT P 730 is one of the largest available, with a build chamber diagonal of more than 1m.

The machine is up to 75% more productive than the P 700, depending on component geometry.

Another recent introduction is the ‘entry level’ FORMIGA P 100, which is capable of production turn-around times of less than 24h.

The fine focus diameter of the laser enables wall thicknesses down to 0.4mm to be built for manufacturing small, detailed plastics components, such as connectors.

Preparation and control of the building process is conveniently carried out off-line at the user’s desk.