The influence of the process parameters on electron beam melting process is investigated and a mathematic model is set up by linear regression analysis. The results show linear relationships of the width of scanning line with the beam current
accelerating voltage
and scanning speed. The quality of layer produced at R
0
egual to 0.5 is better than that produced at R
0
less than 0.5. The heat accumulation can be reduced by spiral scanning so that droplet splash is eliminated and high quality layer is obtained. Aiming at the unmelted powders splash from collision between electron and powders
optimized process parameters is selected to pre-heat the powders to obviously reduce the splash. For the balling of scanning line
the process parameters with the ratio of power to sc
anning speed greater than 0.10 are employed to form a continuous scanning line. One-dimensional scanning line and two-dimensional layer with high performance are obtained by process parameters optimization to lay a foundation for three-dimensional solid object fabrication.
关键词
Keywords
references
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