OK, I admit this isn't an athena question (but it is about how to take the raw data for it!). I want to do biaxial strain measurements. The idea is to deposit a thin film of the material to be investigated on a substrate and then deform the plate with a form of cylindrical symmetry. One can then solve for the stress of a plate using elasticity theory. The twist is that I need a plate that is stiff and (surprise) x-ray transparent ... and heat resistant to about 250 C. Kapton would be a wonderful choice, but is only made in thicknesses up to 175 microns (hardly stiff enough). There must be someone out there in the collective iffeffit world who knows of an appropriate material. Doing some web surfing, I came across another product by DuPont called Vespar that *may* be available in thicker forms. The specs I am looking for are: a thin (semiconducting) film has to stick to the surface, heat resistant to <=250 C, thick enough to be elastically stiff, and x-ray transparent. Any suggestions? Thanks for any help that may come my way in advance! Dr. Paul Fons Senior Researcher National Institute for Advanced Industrial Science & Technology METI Center for Applied Near-Field Optics Research (CANFOR) AIST Central 4, Higashi 1-1-1 Tsukuba, Ibaraki JAPAN 305-8568 tel. +81-298-61-5636 fax. +81-298-61-2939 email: paul-fons@aist.go.jp The lines below are in a Japanese font 〒３０５−８５６８ 茨城県つくば市東１−１−1 つくば中央第４ 近接場光応用工学センター ポール・フォンス主任研究官