Recent content by soptic

Thank you Kenvlach for the valuable NASA article. I will try to get a copy of the work if avalable. It's exactly what we are looking for. Do you thing diamond turning is better than conventional polishing for the substrate manufacturing (less impurities?). Axel

thank you Kenvlach, do you know if your proposed technique is usual for high temperature applications? Will diffusion from SS to the surface degrade the reflectivity with time? Axel

Timelord, The substrate of our mirror must be SS so we cannot use molybdenum laser mirrors. Further, at 800 nm the reflectivity is under 70%. What we need is a coating that exhibits no ageing at high temperatures!

Alexit, we require high relfectivity which remains stable at high temperatures. What do you mean by passivate and electropolish?

Unclesyd, the mirror surface will operate in vaccum.

We are searching for a high reflectivity coating or surface treatment on SS to make mirrors which can operate at up to 600°C without irreversible degradation of the reflectivity at 800 nm wavelength. Any company that can do it for us? Thank you in advance!

A gas bubble detector is available at www.sensoptic.ch which may suit your application

You may find a piezo solution at www.kistler.com or an optical at www.optrand.com

Jim, The components are small mirrors (3 mm diameter) and will see no abrasion. Do you think we will still have expansion mismatch problems, considering that the SiO2 layer is thinner than 1 micron?

We would like to coat a steel substrate (316L) with a highly reflective (> 80%) metallic or dielectric coating for 400°C operating temperature and minimum degradation with time. Is an Al deposition with a SiO2 protection layer a good choice? Thank you in advance.

Kenvlach, We need a strong attachment, in fact, we don't need an electrical contact. The tube serves just as a ferrule to hold the fiber end in a 600°C environement without damage.

Kenvlach, If you suggest gold plating the inside of the tube and not doing brazing at all, how will the fiber be fixed to the tube?

The precision tubes we are using are SS 1.4435 or 1.4301 availabe from medical needles manufacturers in many dimensions. I don't now if other materials are available, for example tubes in Invar or nickel as HIMES suggest. Further, the tubes or ferrules will have to support many thermal cycles...

Thank you ALL for your suggestions, the only problem is that my gold wire in reality is a fused silica optical fiber (diam. 0.36 mm) coated with 30 microns of gold to reach 0.42 mm in diameter. Is there any metal braze alloy which could be applied at 700 - 750 °C (max. temp. indicated by fiber...

I need to solder a 0.42 mm diameter gold wire inside and along a stainless steel tube OD/ID 1.5/0.45 mm and 20 mm long, to resist operating temperatures of 600°C. Any suggestion on how to do it?