Abstract: Regarding the scanning line section outline as an arc of circle and according to the principle of the adjacent scanning line overlap area equals to the groove area, the scanning line spacing is determined. The subarea-scanning mode and the loop-scanning mode are analyzed and compared. In the loop-scanning mode the laser light gate on-off frequency is obviously reduced and the system stability and the part shape precision are improved but the adjacent scanning line infiltration is badly and the gully is deep. In the subarea-scanning mode the scanning line spacing is stable and single and the infiltration is better and the gully is shallow but the light gate moving is frequent and the skip time is more. The scanning mode is improved. Through combining the subarea-scanning and loop-scanning a flawless and full density metal function part is fabricated.

Key words: Metal function part, Metal powder laser shaping, Rapid prototyping, Scanning mode