Diode Laser
Cladding Produces High Quality Coatings
A high power direct diode [HPDDL] laser and
its unique beam make for a highly efficient tool
to use in cladding operations. Laser cladding
is performed by melting a pre-placed powder onto
a substrate to ensure a bond with minimal dilution,
nominal melting and a small heat affected zone.
The laser used in the experiment was the Nuvonyx
ISL-4000L laser mounted on a Panasonic VR-16 robot.
The pre-placed powders chosen for this experiment
are ANVAL 410, 156 and C22. 410 and C22 were selected
for their superior corrosion resistance. 156 is
a general-purpose cobalt hardfacing material.
The cladding substrate was ASTM 1018 steel. The
dilution of the coatings was analyzed through
the use of a Scanning Electron Microscope [SEM].
Through analysis it was discovered that dilution
is kept to a minimum, in the range of 0 to .02%.
The corrosion resistance and wear resistance was
also measured for the appropriate samples. This
process is highly advantageous in comparison with
competing coating methods such as plasma spraying,
arc welding, and other laser sources. The rewards
being lower porosity, reduced post-machining,
optimum edge detail.
Introduction
As tools for use in industrial applications,
HPDDL, also known as semiconductor lasers, are
becoming more prevalent.1,2,3 Diode laser technology
has been used for a number of years in compact
disks, laser printers and laser pointers. Their
low cost, high efficiency, and compact design
make them an attractive technology in the industrial
manufacturing environment. The electrical to optical
conversion efficiency of the HPDDL is as high
as 55%.
