Study on supplying method of assist gas in precision cutting with pulsed YAG laser

Yoshiyuki Uno, Yasuhiro Okamoto, Kazunori Hirose, Shigetaka Kawaguchi, Shin Ichiro Kudota, Naoki Miyanagi

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

YAG laser has widely been used for precision micro machining in many fields. However, adhesions of dross and spatter to base material due to high energy beam machining lead to the deterioration of surface integrity. It is important to understand the assist gas flow from the tip of a convergent nozzle in order to improve the machining accuracy, since most materials are removed away by gas flow. In this paper, the effects of assist gas flow on machined results in micro machining with pulsed YAG laser are investigated using Schlieren method. Experimental analysis made it clear that there was a region in which the pressure on workpiece didn't increase linearly with an increase of cylinder gas pressure. Mach shock disk repeatedly appeared and disappeared under this condition, and the pressure on workpiece changed periodically. The fluctuation of assist gas flow led to the irregular dross generation. On the other hand, there was no unstable region under small gap and/or high pressure conditions, in which the assist gas flow was stable and the height of dross became smaller. Consequently, it is recommended to use the assist gas under higher pressure condition more than 300kPa on workpiece for fine precision machining.

Original languageEnglish
Pages (from-to)1471-1475
Number of pages5
JournalSeimitsu Kogaku Kaishi/Journal of the Japan Society for Precision Engineering
Volume65
Issue number10
Publication statusPublished - Oct 1999
Externally publishedYes

Fingerprint

Pulsed lasers
Flow of gases
Machining
Gases
Gas cylinders
Mach number
Deterioration
Nozzles
Adhesion
Lasers

Keywords

  • Assist gas flow
  • Dross generation
  • Mach shock disk
  • Precision cutting
  • Schlieren method
  • YAG laser

ASJC Scopus subject areas

  • Mechanical Engineering

Cite this

Study on supplying method of assist gas in precision cutting with pulsed YAG laser. / Uno, Yoshiyuki; Okamoto, Yasuhiro; Hirose, Kazunori; Kawaguchi, Shigetaka; Kudota, Shin Ichiro; Miyanagi, Naoki.

In: Seimitsu Kogaku Kaishi/Journal of the Japan Society for Precision Engineering, Vol. 65, No. 10, 10.1999, p. 1471-1475.

Research output: Contribution to journalArticle

Uno, Yoshiyuki ; Okamoto, Yasuhiro ; Hirose, Kazunori ; Kawaguchi, Shigetaka ; Kudota, Shin Ichiro ; Miyanagi, Naoki. / Study on supplying method of assist gas in precision cutting with pulsed YAG laser. In: Seimitsu Kogaku Kaishi/Journal of the Japan Society for Precision Engineering. 1999 ; Vol. 65, No. 10. pp. 1471-1475.
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