Direct Metal Deposition or DMD for short is a relatively recent addition to the ‘additive layer manufacturing’ catalogue.
Put VERY simply the desired end material is injected thru a nozzle into the beam of a CNC controlled Co2 laser where it is melted and deposited in the desired form a layer at a time. Imagine if you will a VERY VERY accurate MIG welder building up the material, but the molten pool generated by a laser and not an electrical arc.
DMD is generating quite an interest in the mould tool making world offering several advantages over traditional toolmaking techniques.
These include the usual ’speed of manufacture’ ‘increased tool performance’ and of ever increasing importance in todays climate ‘greener manufacturing’.
Speed.
Though CNC milling techniques have increased in performance greatly over the last decade thru better machines but more significantly in cutting tool technology, there are some contours a milling machine will struggle with (small radii in deep pockets) or not be able to do at all (square corners). To achieve these dimensions a spark erosion process would be needed. This is inherently a slow process.
Because of DMD’s additive layer technology you have virtual freedom of geometry in your design. So as the buzz phrase is, you can design for performance and not for manufacture.
Increased Performance.
In every case of moulding, the ‘cool down’ time of the part takes up a high percentage of the total mould time. To achieve quicker cool times coolant holes are drilled in the mould tool. These traditionally can only be done in straight lines with drilling apparatus. Because DMD builds up in layers, cooling channels can be added into the build sequence that conform to the shape of the mould surface so greatly increasing the efficiency of the cooling allowing for quicker total mould times. Typical quotes are in the region of 15% with up to 50% being possible on complex shapes.
Greener.
Traditional techniques of manufacture are ’subtractive’ or ‘destructive’. This leads to swarf and chips that have to be collected and processed for re-cycling. A number of different cutting tools to replace when worn or damaged. And also cutting fluids and oils.
With DMD you only get the part you require, with possibly minimum machining required to finish off, as and where required.
DMD is definitely one to keep an eye on for the future…
November 30th, 2007 at 12:12 pm
Direct Metal Deposition or DMD for short is a relatively recent addition to the ‘additive layer manufacturing’ catalogue.
Put VERY simply the desired end material is injected thru a nozzle into the beam of a CNC controlled Co2 laser where it is melted and deposited in the desired form a layer at a time. Imagine if you will a VERY VERY accurate MIG welder building up the material, but the molten pool generated by a laser and not an electrical arc.
DMD is generating quite an interest in the mould tool making world offering several advantages over traditional toolmaking techniques.
These include the usual ’speed of manufacture’ ‘increased tool performance’ and of ever increasing importance in todays climate ‘greener manufacturing’.
Speed.
Though CNC milling techniques have increased in performance greatly over the last decade thru better machines but more significantly in cutting tool technology, there are some contours a milling machine will struggle with (small radii in deep pockets) or not be able to do at all (square corners). To achieve these dimensions a spark erosion process would be needed. This is inherently a slow process.
Because of DMD’s additive layer technology you have virtual freedom of geometry in your design. So as the buzz phrase is, you can design for performance and not for manufacture.
Increased Performance.
In every case of moulding, the ‘cool down’ time of the part takes up a high percentage of the total mould time. To achieve quicker cool times coolant holes are drilled in the mould tool. These traditionally can only be done in straight lines with drilling apparatus. Because DMD builds up in layers, cooling channels can be added into the build sequence that conform to the shape of the mould surface so greatly increasing the efficiency of the cooling allowing for quicker total mould times. Typical quotes are in the region of 15% with up to 50% being possible on complex shapes.
Greener.
Traditional techniques of manufacture are ’subtractive’ or ‘destructive’. This leads to swarf and chips that have to be collected and processed for re-cycling. A number of different cutting tools to replace when worn or damaged. And also cutting fluids and oils.
With DMD you only get the part you require, with possibly minimum machining required to finish off, as and where required.
DMD is definitely one to keep an eye on for the future…