Laser Processing of Carbides and Nitrides of W and Ti (REU Supplement)

该项目是关于激光诱导处理过渡金属碳化物和氮化物的方法。这些基于激光熔化和分解的方法将用于生产W和Ti的碳化物和氮化物层。通过控制激光参数和衬底变量，可以获得从非晶态到多晶态的微结构。激光诱导化学气相沉积将用于形成W和Ti的碳化物和氮化物的层和粉末。碳化物和氮化物的化学组成和化学计量比可以通过调节反应室中组成气体的分压来控制。这些材料将使用TEM/STEM、俄歇、SIMS和RBS技术从微观结构、化学成分、化学计量和均匀性方面进行表征。由激光诱导光解制备的碳化物和氮化物非晶态薄膜有望具有独特的物理和机械性能。选定的薄膜将通过显微硬度和电阻率测量进行评估。不同薄膜的电阻率随温度的变化将作为化学计量比和微结构的函数进行研究。

The project is on laser-induced methods for processing transition metal carbides and nitrides. These methods, based upon laser melting and decomposition, will be used to produce layers of carbides and nitrides of W and Ti. By controlling the laser parameters and substrate variables, microstructures ranging from amorphous to polycrystalline can be obtained. The laser-induced chemical vapor deposition will be used to form layers and powders of carbides and nitrides of W and Ti. The chemical composition and stoichiometry of carbides and nitrides can be controlled by adjusting partial pressures of constituent gaseous species in the reaction chamber. These materials will be characterized using TEM/STEM, Auger, SIMS, and RBS techniques in terms of mircostructures, chemical composition, stoichiometry, and homogeniety. Amorphous films of carbides and nitrides produced by laser-induced photolytic decomposition are expected to have unique physical and mechanical properties. Selected films will be evaluated by microhardness and electrical resistivity measurements. The variation of resistivity with temperature will be studied as a function of stoichiometry and microstructure for various films.