二极管端面抽运固体激光器晶体棒与热沉接触热导研究  

Research on thermal contact conductance between crystal rod and heat sink in LD end-pumped solid-state laser

作　　者：刘海强[1] 过振[1] 王石语[1] 林林[1] 郭龙成[1] 李兵斌[1] 蔡德芳[1] 

机构地区：[1]西安电子科技大学技术物理学院,西安710071

出　　处：《物理学报》2011年第1期299-306,共8页Acta Physica Sinica

摘　　要：二极管端面抽运固体激光器中,圆棒晶体采用金属热沉夹持并散热,晶体侧面受到的压力呈非轴对称分布.建立了此状态下晶体棒与热沉间无热界面物质、采用厚度为平均间隙厚度和远大于平均间隙厚度的热界面物质三种情况下接触热导模型.针对前两种模型,采用截断高斯模型和塑性形变模型,讨论了接触热导与装配压力、等效均方根粗糙度的关系.建立了晶体棒与热沉的接触散热模型,对高斯型热耗分布,采用有限元法得到了无热界面物质和采用铟箔作为热界面物质时晶体棒温度的空间分布.结果表明:无热界面物质时,晶体棒与热沉间接触热导随圆心角变化较大,其值在热沉凹槽底部最大,在两块热沉接触面处最小;装配压力增大或均方根粗糙度减小时,接触热导变大,其均匀性变差,晶体棒温度降低.使用铟箔作为热界面物质时,接触热导及其均匀性得到很大提高,晶体棒温度整体降低,其分布关于光轴对称.In LD end-pumped solid-state laser,the crystal rod is held and cooled by the metal heat sink. The force applied to the side surface of the crystal is non-axisymmetric. Under such circumstances,three kinds of thermal contact conductance （TCC） models are established,including not using thermal interface material,using thermal interface material with its thickness equal to the average thickness of the gaps and using thermal interface material with its thickness much greater than the thickness of the gaps. Regarding to the first two models,the influences of the assembly force and the equivalent root-mean-square （RMS） roughness on thermal contact conductance are discussed based on the Truncated-Gaussian model and the plastic-deformation model. The contact heat dissipation model of the crystal rod and the heat sink is established. For the Gaussian heat consumption,the spatial distributions of temperature inside the crystal with and without thermal interface material are obtained by the finite element method. The results show that without thermal interface material,the thermal contact conductance between the crystal rod and the heat sink changes significantly in the circumferential direction,which reaches a maximum on the bottom of the heat sink groove and a minimum on the contact area of the heat sink couple. With the assembly force increasing and the equivalent root-mean-square roughness decreasing,the thermal contact conductance gets larger and more nonuniform,and the temperature of the whole crystal rod reduces. When the indium foil is used as thermal interface material,the thermal contact conductance gets larger and more uniform,the temperature of the whole crystal rod reduces as well and its distribution is axisymmetric.

关 键 词：激光二极管端面抽运固体激光器 热效应 有限元法 接触热导 

分 类 号：TN248[电子电信—物理电子学]