During selective electron beam melting (SEBM) process

powder particles are negatively charged by the electron beam causing coulombic interactions

which is easy to cause the powder scattering and smoking phenomenon. This phenomena can lead to problems such as electron gun discharge

unstable beam current

uneven powder spreading

etc.

which in turn will cause process instability and stop processing. In order to expand the application scope of SEBM process

based on the interaction characteristics between the electron beam and the powder

the mechanism and factors for the formation of powder smoking were analysed and summarised in terms of powder characteristics and process parameters. Based on the ways to reduce the electrostatic force between powders

from which measures to prevent powder smoking were summarised

further directions for basic research on powder smoking in SEBM were described. This is to provide a reference for the long-term work stability

reliability improvement and quality enhancement of SEBM.