Metal 3d printing is a method for making metal parts that begin as a computer model containing a description of the part geometry. A layer of the part is built by depositing a thin layer of metal alloy powder onto a bed of powder on a print platform. The platform holding the part and the bed move in three dimensions, while a laser or electron beam moves back and forth through space along an axis, scanning the cross-section of the part from one point to another. In this way, new layers are built up, one on top of another, until the entire part has been printed by metal 3d printing.
Metal 3d printing costs
With metal 3D printing, one can build metal parts with very high accuracy. This is very important for the manufacture of the high-precision part. Metal printing is stronger, more durable, and more rigid than the traditional machining processes used to make metal parts. With metal 3d printing, one can build parts with tighter tolerances than is possible with machining.
Metal 3D printing is not cheap, though. The printers are expensive, in part because they require expensive materials. Metal powder, for example, costs about $300 a pound. Given the low output per cubic foot of powder, this means that it takes 225 pounds of powder at current prices to make a single cubic foot of metal part. This powder must be mixed, which requires a lot of power. The printers are large, too, and take up a lot of floor space.
Metal 3D printing is improving, though. The printers are getting faster, and the power costs are becoming more reasonable. And researchers are exploring ways to print objects from liquid metal.
Metal vs. resin
A key difference between 3D printing with metal and resin is that metal is very strong. It can not only withstand the stresses of printing but can also be bent into complex shapes. Resin, on the other hand, is relatively weak. The stresses of printing can cause the layers to bond together.
Because metal is so strong, metal printing is very expensive. A metal printer costs $50,000 or so, and one needs a special material as well, about $10 a gram. Resin printing is much cheaper, at $150 or so. But, unlike metal, one needs special resin as well, about $3 a gram.
There are other differences as well. The melting point of the metal is much higher than for resin, so metal is easier to work. The melting point of resin is quite high, making it harder to print. Traditionally, metal printing has been used for making smaller objects, such as crowns, jewelry, and dental prosthetics. Resin printing is used to make larger objects, such as prosthetic limbs and replacement body parts.
These differences point to two possible futures. One future is for 3D printers to become cheap enough to be widely used. Then, people with 3D printers could print their crowns, jewelry, and dental prosthetics.
The other future is for 3D printers to become obsolete, replaced by conventional manufacturing. In these futures, 3D printers would still make objects that can’t be made by conventional manufacturing, such as replacement body parts. But, essentially, they would be making the same thing conventional manufacturing is making, only more slowly. The 3D printing industry has not yet decided on which future it wants.