Precision Measurements of Gamma Coarsening at Low Volume Fractions in Nickel-Base Alloys

本文探讨了金属中沉淀粗化的机理 含有低体积分数沉淀物的合金。 的 沉淀粗化的机制和相关影响 弹性应变是物理冶金学中的重要领域， 需要解决。选择了四种二元合金， 这项研究提供了一系列的晶格失配，从低的 0.003的镍/硅系统中的0.0112的高 镍/锗系统 弹性相互作用的影响， 沉淀物体积分数对颗粒粗化和 平衡形状进行了检查。 粗化的动力学是 随后使用透射电子显微镜技术 和磁性分析，这使得能够测量溶质 在粗化过程中富Ni基体中的浓度。 磁控 探索溅射作为制备精确的合金的方法， 控制成分和均匀性。 %%% 这项研究与微观结构的形成有关， 高温金属合金的稳定性。 重点是 二元镍基合金，高温合金的主要基础 成分发展。

This effort explores mechanisms of precipitate coarsening in metal alloys that contain low volume fractions of precipitates. The mechanisms of precipitate coarsening and associated effects of elastic strain are important areas in physical metallurgy that needs to be resolved. Four binary alloys have been selected for this study to provide a range of lattice mismatches, from a low of 0.003 in the nickel/silicon system to a high of 0.0112 in the nickel/germanium system. The effects of elastic interaction and volume fraction of precipitate on particle coarsening and equilibrium shape are examined. The kinetics of coarsening are followed using the techniques of transmission electron microscopy and magnetic analysis, which enables measurement of the solute concentration in the Ni-rich matrix during coarsening. Magnetron sputtering is explored as a means of preparing alloys of precisely controlled compositions and homogeneity. %%% This research has relevance to microstructural formation and stability in high temperature metal alloys. The emphasis is on binary nickel-base alloys, the principal base for superalloy compositions development.