This study investigates the characteristics of the remelted layer in DD6 nickel-based single-crystal superalloy processed with a water-jet guided laser (WJGL). Analysis focused on changes in surface morphology, elemental distribution, and crystal structure. WJGL induced periodic thermal stresses, forming distinct ridges within the remelted layer, which differ in morphology from the unprocessed matrix. At the interface, interactions between oxygen and elements such as aluminum, nickel, and chromium led to the formation of oxides, which are strategically evaluated for their role in surface transformations. The oxygen diffusion coefficient, calculated at 1.5×10⁻¹⁵ m²/s using Fick's second law, illustrates the extent of these interactions. The study also reveals thin polycrystalline layers with minimal orientation deviations from the matrix, maintaining the alloy's overall structural integrity. Additionally, the processing direction was found to influence the crystal orientation in the remelted layer, moderated by the turbulence from the water jet. These findings contribute to understanding the microstructural effects of WJGL processing, with implications for optimizing high-temperature alloy applications in aerospace engineering.

中文翻译：

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水射流引导激光加工分析 DD6 单晶高温合金的重熔层


本研究研究了水射流引导激光 （WJGL） 加工的 DD6 镍基单晶高温合金中重熔层的特性。分析的重点是表面形态、元素分布和晶体结构的变化。WJGL 诱导周期性热应力，在重熔层内形成明显的脊，其形态与未加工的基体不同。在界面处，氧与铝、镍和铬等元素之间的相互作用导致氧化物的形成，这些氧化物因其在表面转变中的作用而受到战略评估。使用 Fick 第二定律计算的氧扩散系数为 1.5×10⁻¹⁵ m²/s，说明了这些相互作用的程度。该研究还揭示了与基体方向偏差最小的薄多晶层，保持了合金的整体结构完整性。此外，发现加工方向会影响重熔层中的晶体取向，受水射流湍流的调节。这些发现有助于理解 WJGL 加工的微观结构效应，对优化航空航天工程中的高温合金应用具有重要意义。