(1. Dental Laboratory, Peking University School and Hospital of Stomatology & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key Laboratory of Digital Stomatology,Beijing 100081, China)
(2. Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China)
The microstructure difference of the CoCr alloys fabricated by a cast technique and a SLM (selective laser melting) technique is investigated, and the reasons causing the different microstructures and the effects of the different microstructures on the properties of the CoCr alloys are discussed. The CoCr alloy powder and bulk with similar compositions are selected to prepare CoCr samples using the SLM technique and the cast technique, respectively. The microstructures of the fabricated CoCr samples are investigated by SEM and the chemical compositions of featured areas are analyzed by EDX. The microstructure of the CoCr alloy fabricated by the SLM technique is uniform without phase separation. However, the phase separation rich in Mo element is found in the CoCr alloys fabricated by both the centrifugal cast technique and the vacuum cast technique. The CoCr samples fabricated by the SLM technique and the cast technique both contain less pores. In conclusion, the quality of the CoCr alloy fabricated by the SLM technique is better than the cast technique.