Collaborative Research: Composite Surfacing of Amorphous Materials by Laser Interference Nanopatterning

这项合作研究的目标是开发一种新的基于激光的表面工程技术，以提高非晶体材料（主要是金属）的延展性。激光干涉图像化将用于在这些材料表面产生具有残余应力的局部超细晶粒结构的周期性线或点的修饰区域。本研究的主要目标是：(1)确定干涉图版过程中与调制激光强度相互作用相关的热物理效应；(2)表征激光图版过程中调制的微观结构、结晶动力学和残余应力分布。这些目标将有助于确定表面改性在提高非晶材料整体塑性方面的作用。最后，将建立一个基于非晶材料表面激光干涉图案化相关的热物理相互作用的计算模型。该激光干涉图样项目的成功完成将极大地推进固有脆性非晶合金延展性的最新技术，从而使这些材料在先进结构应用中得到更广泛的接受。本研究将通过设计由原始非晶区和带有残余应力的超细晶粒结构区组成的周期性表面结构，阐明非晶材料塑性增强的基本机理。通过计算与实验相结合的方法，为新一代结构材料体系的设计与合成提供一种方法。此外，该合作项目将为学生提供机会，研究新颖先进的加工方法和材料，并帮助培养下一代全球科学家/工程师的多样化和有能力的劳动力。

The goal of this collaborative research grant is the development of a novel laser-based surface engineering technique to enhance the ductility of non-crystalline materials, primarily metals. Laser interference patterning will be employed to produce modified regions of periodic lines or dots of localized ultrafine grain structure with residual stresses on the surface of these materials. The major objectives of the research are (i) to identify the thermo-physical effects associated with the interaction of modulated laser intensity during interference patterning and (ii) to characterize the modulated microstructure, crystallization dynamics, and distribution of residual stresses during laser patterning. These objectives will be instrumental in establishing the role of surface modification on enhancing global plasticity of the non-crystalline materials. Finally, a computational model based on the thermo-physical interactions associated with laser interference patterning of non-crystalline material surfaces for tailoring the effects will be developed.Successful completion of this project on laser interference patterning will significantly advance the state-of-the-art in ductilization of inherently brittle non-crystalline alloys leading to wider acceptance of these materials for advanced structural applications. The research will elucidate the fundamental mechanisms of plasticity enhancement of non-crystalline materials through design of periodic surface structures consisting of original non-crystalline regions and regions of ultrafine grain structure with residual stresses. Through synergistic computational and experimental approach, the research is expected to establish a methodology for design and synthesis of next generation structural materials system. Furthermore, the collaborative project will provide opportunities for students to work on novel and advanced processing methods and materials and will help prepare diverse and capable workforce of next generation global scientists/engineers.