| 摘要 |
Glass compositions having a Young's modulus of at least 16 million psi and a specific modulus of at least 110 million inches consisting essentially of approximately, by weight, 20-43% SiO2, 8-21% Al2O3, 4-10% BeO, 27-58% of at least one oxide selected from a first group consisting of Y2O3, La2O3, Nd2O3, Ce2O3 and the mixed rare earth oxides and 3-12% of at least one oxide selected from a second group consisting of MgO, ZrO2, ZnO and CaO, the molar ratio of BeO to the total content of said first group oxides being from 1.0-3.0.
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