Research Initiation: Solid-Liquid Interface Morphology During Welding

本研究的目的是了解 不同固液界面形态的出现 在单个和 多晶薄板 这项研究将确定 热流、表面张力、界面动力学效应和 晶界作用（包括 晶体学各向异性）在熔池的发展中 形状和熔合区的合成性质。 方法 研究内容包括固-液熔池的数值计算 接口建模为非线性自由或移动边界， 考虑热流，并与界面耦合 性质，有限差分，有限元，谱 和/或边界积分技术。 此外，数字 熔池形状类别中的急剧过渡的计算 使用解析（线性和非线性）渐近分析 将在适用时进行;分析将是有帮助的 在获得特殊极限情况的更清楚的知识， 与数值结果的比较。 结果将 与现有的实验结果相比，目标是 最终提供一组焊接之间的相关性 条件和最终材料性能。 这将提供一个 了解可能消除的焊接方法类型 或避开有害的焊池形状特征， 用于产生缺陷的部位和纹理化的熔合区。 该项目具有提高质量和控制的潜力 焊接过程中。

The goals of this research are to understand the reasons for the appearance of different solid-liquid interface morphologies during the autogenous full penetration welding of single and polycrystalline thin plates. The research will identify the role that heat flow, surface tension, interfacial kinetic effects and grain boundaries play (which include the effects of crystallographic anisotropy) in the development of the weld pool shape and the resultant properties of the fusion zone. Methods of research include numerical calculation of solid-liquid weld pool interfaces modeled as nonlinear free or moving boundaries, that account for heat flow and are coupled with the interfacial properties, by using finite difference, finite element, spectral and/or boundary integral techniques. Furthermore, numerical calculation of sharp transitions in classes of weld pool shapes using analytical (both linear and nonlinear) asymptotic analysis will be performed whenever applicable; the analysis will be helpful in gaining a clearer knowledge of special limiting cases and for comparison with the numerical results. The results will be compared to existing experimental results, and the goal is to ultimately provide a correlation between a set of welding conditions and final material properties. This would provide an understanding of the types of welding methods that might eliminate or circumvent deleterious weld pools shape features which give rise to sites for defect generation and textured fusion zones. The project has potential to improve the quality and control of the welding process.