Abstract
Powder feeding is one of the single most important
parameter that defines a qualitative outcome of the
cladding process. This study focuses on how powder
feeding angle and powder carrying gas flow rate effects
on the powder cloud behavior in laser cladding with
scanning optics. Focus of this study is to provide the
knowledge on how scanned laser beam affects the powder
cloud and what kind of phenomena's can occur during
cladding process.
In this study, powder feeding angles from 40 to 70
degrees were tested with powder feeding gas flow rates of
3 and 6 l/min and with laser scanning frequencies ranging
from 80 to 150 Hz. Powder material used was 316L, and the
substrate material was low alloyed steel. The results
showed that the stability of the powder cloud was highly
dependent on the tested parameters. At a steep powder
feeding angle, the powder cloud under laser radiation was
strongly vaporized, emitting bright visible light.
However at gently sloping powder feeding angle the powder
cloud behavior was more stable; i.e. less or no
vaporization was noticed, and the emitted light was
fainter. Also, a direct correlation between the
vaporization of the powder cloud and the increase of
dilution was noticed. It was determined to be cause of
vapor flow disturbing the powder feeding into the melt
pool and thereby increasing dilution.
| Original language | English |
|---|---|
| Pages (from-to) | 032007-1 - 032007-12 |
| Journal | Journal of Laser Applications |
| Volume | 28 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 2016 |
| MoE publication type | A1 Journal article-refereed |
Keywords
- powder cloud
- process stability
- laser cladding
- scanning frequency
- machine vision
