论文部分内容阅读
早在1829年,法拉弟就开始用铂器皿熔炼出较新和较纯的玻璃。至今,熔炼高纯度的光学玻璃都使用铂坩埚。这是因为铂具有非常独特的化学惰性,是唯一可以在高温强氧化条件下使用的金属材料。但在长期的使用过程中,发现铂坩埚存在着强度低、高温抗蠕变性能差,在某些场合高温耐腐蚀性能也较差等弱点,以致缩短或大大缩短了铂坩埚的使用寿命。这样,纯铂坩埚已不能适应某些玻璃的熔炼要求,而促使人们去寻求新的铂坩埚材料。这种新型铂坩埚材料必须满足三个要求:①具有较佳的高温持久强
As early as 1829, Faraday began to smelt newer and purer glass with platinum vessels. To date, platinum crucibles have been used to melt high purity optical glass. This is because platinum has a very unique chemical inertness and is the only metal material that can be used under high temperature and high oxidation conditions. However, during the long-term use, it has been found that platinum crucibles have weaknesses such as low strength, high temperature creep resistance, and poor high temperature corrosion resistance in some cases, which shortens or shortens the service life of the platinum crucible. In this way, pure platinum crucible has been unable to meet the melting requirements of some of the glass, prompting people to seek new platinum crucible material. This new platinum crucible material must meet three requirements: ① has a better high temperature and long-lasting