Home Products Beryllium Products Beryllium Metal O-30-H O-30-H GRADE BERYLLIUM O-30-H grade beryllium is hot isostatically pressed beryllium consisting of 99% beryllium with a maximum of 0.5% beryllium oxide. Low oxide grades are preferred for bare beryllium mirrors because they yield a lower level scatter and polish easier than higher oxide grades. O-30-H beryllium was chosen for the primary optics for the James Webb Space Telescope. TENSILE PROPERTIES Minimum tensile properties for the material at room temperature (testing compliant with ASTM E-8). Ultimate Tensile Strength, psi, minimum 50.0 (345 Mpa) Yield Strength (0.2% offset), psi, minimum 30.0 (207 Mpa) Elongation (% in 4 diameters), minimum 2.0 Micro-yield Strength, ksi 3.0 (21 MPa) AVAILABLE DESIGN CONFIGURATIONS Available in rod or bar. Special sizes and shapes can be made.