| 摘要 |
An additive manufacturing method to form three-dimensional products made from powder bed of a high melting point metal powder (above 2400ºC) disposed on a build surface of the same or a different metal also having a melting point above 2400ºC. Melting the metal powder using a laser with parameters optimised at 300 to 1000 Watts output and 525 to 3000 mm/s scanning speed, producing tracks 25-250 microns apart (ideally 50-80 microns) and a layer thickness of 0.1 to 100 microns. Preferably a single refractory metal powder is used such as tungsten, tantalum or molybdenum and a metal ion solution treatment step is preferably absent. The product may have a theoretical density of 93 to 97 percent and the first metal which forms at least part of a product is entirely crystalline. |
