The comparison of melt pool temperature and the clad formation between continuous wave and pulsed Nd:YAG laser cladding of stellite 6 on stainless steel was made. The melt pool temperature in the CW laser cladding is roughly constant and increases with laser power, whereas the melt pool temperature in the pulsed laser cladding shows large fluctuation. Both pulse peak temperature ( Tp ) and the duration ( t1 ) when the melt pool temperature is above the melting point of stellite 6 powder increase with laser power.

Clad height of the CW laser cladding increases smoothly with the laser power due to the increase of melt pool temperature (size), however, the increase of clad height of the pulsed laser cladding with the laser power is faster because of the increases of both Tp and t1 . For the same average power, the clad height in pulsed laser cladding at high pulse frequency is higher than that at the lower pulse frequency, and the total clad thickness in pulsed laser cladding is higher than that in CW laser cladding due to the effect of peak power. Therefore, higher powder mass flow rate is required for pulsed laser cladding.

1.
Steen
W. M.
,
Weerasinghe
V. M.
and
Monson
P.
(
1986
)
Some aspects of formation of laser clad tracks
, in
Proceedings of SPIE
Vol.
650
:
High power laser and their industrial applications
,
226
234
.
2.
Weerasinghe
V. M.
,
Steen
W. M.
(
1983
)
Laser cladding by powder injection
,
Proceedings of the 1st International Conference on Lasers in Manufacturing
, p.
125
.
3.
Shepeleva
L.
,
Medres
B.
,
Kaplan
W. D.
,
Bamberger
M.
and
Weisheit
A.
(
2000
)
Laser cladding of turbine blade
,
Surface and Coatings Technology
125
,
45
48
.
4.
Kathuria
,
Y. P.
(
2000
)
Some aspects of laser surface cladding in the turbine industry
,
Surface and Coatings Technology
132
,
262
269
.
5.
Peters
T.
and
Jahnen
W.
(
2002
).
Steam turbine leading edge repair by stellite laser cladding
,
Proceedings of EPRI
, ST7.
6.
So
H.
,
Chen
C. T.
and
Chen
Y. A.
(
1996
)
Wear behaviors of laser-clad stellite alloy 6
,
Wear
192
,
78
84
.
7.
Colaco
R.
,
Carvalho
T.
and
Vilar
R.
(
1994
)
Laser cladding of stellite 6 on steel substrate
,
High Temp. Chem. Processes
3
,
21
29
.
8.
De Hosson
J. T. M.
and
De Mol
van Otterloo
L. (
1997
)
Surface engineering with lasers: application to Co based materials
,
Surface Engineering
13
,
471
481
.
9.
Frenk
A.
,
Vandyoussefi
M.
,
Wagniere
J.-D.
,
Zryd
A.
and
Kurz
W.
(
1997
)
Analysis of the laser-cladding process for stellite on steel
,
Metallurgical and Materials Transactions
28B
,
501
508
.
10.
Sun
S.
,
Durandet
Y.
and
Brandt
M.
(
2003
)
Pulsed laser cladding of stellite 6 on stainless steel
, in
Proceedings of WTIA Surface Engineering Conference
,
Sydney, Australia
.
11.
Corbin
S.F.
,
Toyserkani
E.
,
Khajepour
A.
(
2003
)
Cladding of an Fe-aluminide coating on mild steel using pulsed laser assisted powder deposition
,
Materials Science and Engineering
A354
,
48
57
.
12.
Pinkerton
A.J.
,
Li
L.
(
2003
)
An investigation of the effect of pulse frequency in laser multiple-layer cladding of stainless steel
,
Applied Surface Science
,
208
209
, 405-410.
13.
Laser Zentrum Hannover e.vV
.
Closed-loop process control for non-plasma laser material processing.
14.
Sun
S.
,
Durandet
Y.
and
Brandt
M.
(
2004
)
Correlation between melt pool temperature and clad formation in pulsed and continuous wave Nd:YAG laser cladding of stellite 6
,
Proceedings of the 1st Pacific International Conference on Application of Lasers and Optics
.
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