Hi,

Radha

There are few ways to improve the absorption of electromagnetic waves in metal surface, but before that, you should be very specific for which region of the electromagnetic wave band you are interested.

For example: Metals like Al, Cu, Ag shows very good absorptivity in the Ultra violet region. whereas, in infrared red region the absorptivity is very less (~ 2-5%).

Generally there will be few ways of improving the absorption of electromagnetic waves from U.V to far infrared region.

(i) increase the temperature of the metal substrate.

(ii) increase the roughness of metal surface.

(iii) put a thin coating of Carbon over the metal surface.

Soumitro Mahanty i am trying to enhance the laser beam absorption in dissimilar metal welding of SS to MS.

The three options given by Mahanty at the end can be good options for laser beam welding.

1. Increase roughness of metal surface.

2. The shape of metal surface may be made parabolic (Concave) if suitable to your experiment.

you can increase absorption of electromagnetic rays in metals by:

Increase the roughness of metal surface.

Increase the temperature of the metal substrate.

Hi Radha,

If you want to joint these two material through the laser welding.

then few things could be useful .

(1) do sand blasting for the sample pieces, before the laser welding. It enhance the surface roughness and absorb more laser photons.

(2) If possible put a coating of carbon film in the welding region.

(3) here i am not suggesting you to increase the substrate temperature. Because in this case your material microstructure may get change.

Hope it may work.

cheers!