Global chemical giant BASF has entered the 3D printing materials industry. At the 2018 TCT booth, BASF introduced a wire 3D printing wire. After printing and molding with an FDM 3D printer, metal parts can be obtained. Compared with the general laser molten metal 3D printing process, the cost has been reduced by more than 10 times. Because ordinary SLM process metal 3D printers cost 1 million to 10 million yuan, and the cost of metal powder materials is relatively high; while FDM 3D printers can cost thousands to tens of thousands of yuan.
3D printed metal forming parts with adhesive material
Partially removed metal parts by baking degreasing
High temperature sintering, remove all bonding materials, metal powder shrinks into final metal products
Antarctic Bear learned that the FDM process realizes the principle of metal 3D printing:
① metal powder (such as stainless steel 316) and a binding material (usually a polymer, such as resin) are fully mixed and drawn into a wire;
Stainless steel, copper metal 3D printing wire
② Use FDM 3D printer (nozzle needs high strength and high abrasion resistance, because the metal mixture can easily wear the nozzle; for brass nozzles, it is recommended to use a roll of material for another nozzle, of course, it is better to use a nozzle with high abrasion resistance), The nozzle melts the wire at a high temperature (for example, above 300 ° C), sprays it out of the nozzle, and superimposes it to form a preliminary metal part;
③ The metal parts are degreased by heating, and most of the bonding material is evaporated (the part will shrink at this time), and some remaining bonding materials hold them loosely together;
④ High-temperature sintering (for example, 1300 ° C), remove all bonding materials, and the product further shrinks into a firm final product.
⑤ Compared with the metal parts just printed and formed, the volume of the sintered metal parts shrinks to 60% (two major reasons: the volume occupied by the bonding material is shaved off; the space between the powders is reduced and becomes denser) , The quality is reduced to 80% (20% of the mass is the bonding material, all evaporated)
The cost of 3D printing metal in the FDM process is less than 10% of the traditional metal 3D printing process, which has a very strong appeal for the general industry. A factory in the mold industry once told Antarctic Bear that if the metal 3D printing cost of the SLM process can be reduced by more than 60%, then in the mold industry, metal 3D printing will be able to achieve large-scale applications.