Abstract Transparent Al-rich spinel ceramics (MgO·nAl 2 O 3 , n = 1.05–2.5) were prepared by reactive sintering in air followed by the hot isostatic press (HIP). Commercial MgO and γ-Al 2 O 3 powders were used as the raw materials, and the effects of composition and HIP temperature on the transmittance and microstructure of resulting samples were investigated. To obtain the high optical quality, extra alumina (n ≥ 1.1) was used to help eliminate residual pores and suppress abnormal grain growth during the sintering process. The appropriate HIP temperature was also critical to realize the single-phase formation and prevent the generation of second-phase precipitates. The resulting samples with n = 1.1 and 1.3 exhibited excellent optical quality and fine grains below 5 µm after HIPed at 1550 °C.

中文翻译：

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反应烧结制备高品质透明富铝尖晶石陶瓷

摘要 通过在空气中反应烧结和热等静压（HIP）制备透明富铝尖晶石陶瓷（MgO·nAl 2 O 3 ，n = 1.05-2.5）。以市售MgO和γ-Al 2 O 3 粉末为原料，研究了成分和HIP温度对所得样品透光率和微观结构的影响。为了获得高光学质量，使用额外的氧化铝（n ≥ 1.1）来帮助消除残余孔隙并抑制烧结过程中的异常晶粒生长。适当的 HIP 温度对于实现单相形成和防止第二相沉淀的产生也很关键。n = 1.1 和 1.3 的所得样品在 1550 °C 下 HIP 后表现出优异的光学质量和小于 5 µm 的细晶粒。