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氧化鋁陶瓷又稱半透明氧化鋁陶瓷或透明多晶氧化鋁陶瓷。主晶相為α-A12O3。密度3.98g/cm3以上。直線透光率90％～95％以上。介電常數大于9.8。介電損耗角正切值小于2.5×10-4(1GC)，抗彎強度大于350～380MPa。擊穿強度6.0～6.4kV/mm。熱膨脹系數(6.5～8.5)×10-6/℃。高溫下具有良好耐堿金屬蒸氣腐蝕性。 　　
原料為純度99.99％以上的Al2O3，添加少量純氧化鎂、三氧化二鑭、或三氧化二釔等添加劑，采用連續等靜壓成型，氣氛燒結或熱壓燒結，嚴格控制晶粒大小，可獲得高致密透明陶瓷。用于制造高壓鈉燈的發光管(工作壽命可超過2萬h)。也可用作微波集成電路基片、軸承材料、耐磨表面材料和紅外光學元件材料等。（圖/文hytlfdc.com）
中譯英：
 Alumina ceramic is also called translucent alumina ceramic or transparent polycrystalline alumina ceramics. The main crystalline phaseα -A12O3. The density of 3.98g/cm3and above. Linear transmittance90%～ 95% above. A dielectric constant greater than 9.8. Dielectric loss angle tangent value is less than2.5 × 10-4(1GC ), high temperature alkali metal vapor having good corrosion resistance.

Raw materials for the purity of more than 99.99% Al2O3, add a small amount of pure magnesium oxide, lanthanum oxide, three two or three two yttrium oxide additives, continuous isostatic pressing, sintering or hot pressing sintering atmosphere, strictly control the grain size, can obtain high dense transparent ceramics. Used in the manufacture of high pressure sodium lamp led. Can also be used as a microwave integrated circuit substrate, bearing material, wear-resistant surface materials and infrared optical material.