【摘要】 对于采用电阻加热导模法生长白宝石弓形片来说,模具顶端的温度场对晶体外形控制起着关键作用。实验发现模具顶端附近径向温度梯度1.6℃/mm、轴向温度梯度3.3℃/mm时,晶体生长较易获得理想的晶体外形。对于晶体生长过程中产生的气泡,实验设计了合适的模具、找到了适宜的工艺参数,有效地解决了这个问题。小角晶界的产生,可通过选用高质量的籽晶、采用缩径放肩工艺、调整模具顶端的形状来消除。通过这些问题的解决,实验生长出外形(2.6×30×240)mm和晶体内部质量符合手表镜面要求的白宝石弓形片。更多还原

【Abstract】 When white sapphire arch sheet is grown using EFG heated by resistance,the temperature field on the top of mould is a key to the controlling of crystal’s shape.The experiments found when radial temperature gradient was 1.6℃/mm and axial temperature gradient was 3.3℃/mm,the crystal with ideal shape formed easily.In order to eliminate the bubbles occurring during crystal growth,a fit mould was designed and suitable technological parameters were determined for the experiment.Low angle crystal boundary could be eliminated by use of high quality seed crystal,the technology of decreasing diameter and releasing shoulder and adjusting the shape of top of the mould.After solving these problems,sapphire arch sheet with the size of 2.6×30×240mm was produced experimentally and its internal quality meets the requirement of the mirror surface of watch.更多还原