高品质超低膨胀透明微晶玻璃实现批量化生产

锂铝硅系超低膨胀微晶玻璃是一种性能优良的低膨胀光学材料,热膨胀系数低、透明性好。国产高品质超低膨胀微晶玻璃一直受到技术制约,难以批量化生产。本研究采用熔融法结合搅拌工艺以及适宜的热处理制度,成功批量化生产出热膨胀系数接近于零的高品质超低膨胀透明微晶玻璃产品,产品外观完整,内部基本无气泡、条纹等缺陷。对优级产品进行热膨胀系数、应力双折射、抗弯强度测试,结果表明,优级产品热膨胀系数为1.6×10^-8 K^-1,应力双折射小于2 nm/cm,抗弯强度高达171 MPa,品质已达到ZERODUR零级。采用XRD、SEM、TEM等手段对该产品的物相组成、表面形貌、微观结构进行了分析研究,产品主晶相为β-石英固溶体,晶相含量较高且分布均匀,晶粒尺寸为几十纳米,保证了其极低的热膨胀系数和高透明性。

High Quality Ultra-Low Expansion Transparent Glass-Ceramics Achieve Mass Production

Li₂O-Al₂O₃-SiO₂ system ultra-low expansion glass-ceramics is a kind of low expansion optical material with excellent performance, it has low thermal expansion coefficient and good transparency. Domestic high quality ultra-low expansion glass-ceramics has been subject to technical constraints and it is difficult to achieve mass production. In this study, high quality ultra-low expansion transparent glass-ceramics with near-zero thermal expansion coefficient were successfully manufactured by melting method, stirring process and suitable heat treatment system, the appearance of the product were complete, there were basically no bubbles, stripes and other defects inside the product. The thermal expansion coefficient, stress birefringence and flexural strength of the superior product were tested. The results show that the coefficient of thermal expansion of the superior product is 1.6×10^-8 K^-1, the stress birefringence is less than 2 nm/cm, the flexural strength is 171 MPa, and the quality has reachedZERODUR zero grade. The phase composition, surface morphology and microstructure of the product were analyzed through XRD, SEM and TEM. The main crystalline phase of the product is β-quartz solid solution, the content of the crystalline phase is high and the distribution is uniform, the grain size is tens of nanometers, which ensures the extremely low coefficient of thermal expansion and high transparency.