copper backing

[laserace]

Can anyone offer a backing material other than copper that they have had goog results with please? I work in an aerospace company that has a new Mits co2 vz1 laser. I am currently using copper as a backing but having some problems with reflection. Thanks in advance.

 

[Timelord]

laserace,

I don't know much about laser welding and cutting, but "big" lasers are sommething I know about. I assume you are asking about a backup plate for a weld. We always used a piece of graphite for beam dumps for Multi-kilowatt class lasers. Little reflection off the surface and the surface slowely ablates when hit with a high power beam. A material called Grafoil works especially good. It is a sheet material made for vacuum (radiant) insulation. It has good heat transfer laterally, but poor thru the sheet. I had a real thin piece mounted on the wall opposite the aperature of a highly collimated 6kW laser and it only got hot. Never burned a hole in it.

Timelord

 

[laserace]

Sorry for the delay. Thanks for your input. The application is cutting and we cannot have any graphite in contact with the part which is made of hast-x. The problem is possible contamination and crack problems with engine heat.