Pulsed laser micro and nano manufacturing

我的研究小组最近的研究表明，MHz重复频率飞秒激光器是微/纳米制造的一种独特有用的工具。MHz飞秒激光可以实现新材料和新工艺。目前的提案是在这些新发现的基础上制定的，旨在了解纳米材料形成的基本原理，并产生新的工具和知识，使下一代产品的制造能够在航空航天工业中找到潜在的应用。研究计划包括基础研究和工艺开发。 基础研究旨在发现工艺参数对生成的纳米材料和纳米特征的影响。特别是，该计划将研究兆赫兹飞秒激光烧蚀所特有的现象：1）Voronoi图案化的纳米颗粒团聚，2）从辐照的玻璃基板中拉伸纳米纤维，3）纳米尖端形成，4）在烧蚀阈值下辐照的快速氧化和非晶化，以及5）PDMS的瞬时固化。从建模研究中获得的知识将用于改进或启用可用于控制纳米材料生成和微/纳米结构制造的工艺。 工艺发展将集中在两个方向：（1）提高快速特定位置氧化和非晶化的分辨率和加工质量; 2）使用纳米材料增强聚合物纳米复合材料制造微/纳米特征。通过兆赫兹飞秒激光烧蚀合成的各种形式的纳米材料将用作增强填料。 纳米材料分散在聚合物树脂中，通过双光子聚合或局部热固化可以制备出微米或纳米尺度的纳米复合结构。 这项研究计划的一个重要方面是HQP培训。总共有12名学生将接受培训，不仅有技术知识和技能，而且还有未来职业生涯所需的非技术技能。

Recent investigations by my research group have demonstrated that MHz repetition frequency femtosecond lasers are a uniquely useful tool for micro/nano-manufacturing. New materials and new processes can be enabled with the MHz femtosecond laser. The current proposal is developed on these new findings and aimed at understanding the fundamentals of nanomaterials formation and generating new tools and knowledge that will enable the fabrication of next generation products that find potential applications in aerospace industry. The research program involves fundamental study and process development. Fundamental study is intended to find the effect of processing parameters on the generated nanomaterials and nanofeatures. Particularly, this program will investigate phenomenon that are unique to Mega Hertz femtosecond laser ablation: 1) Voronoi-patterned nanoparticle agglomeration, 2) nano-fiber drawing from irradiated glass substrate, 3) nano-tips formation 4) rapid oxidization and amorphization with irradiation under ablation threshold and 5) instantaneous curing of PDMS. Knowledge derived from modelling studies will be used to improve or enable processes that could be used to control the generation of nanomaterial and the fabrication of micro/nano-structures. Process development will concentrate in two directions: (1) improve the resolution and machining quality of rapid site-specific oxidization and amorphization; 2) Fabrication of micro/nano features using nanomaterial-reinforced polymer nanocomposites. Various forms of nanomaterials that synthesized through Mega Hertz femtosecond laser ablation will be used as reinforcement fillers. Nano-composite features with dimensions in micro or nano-scale will be fabricated through either two-photon polymerization or localized thermal curing of nano-materials dispersed polymer resin. An important aspect of this research program is HQP training. In total, twelve students will be trained with not only technology acknowledge and skills but also nontechnical skills needed in their future careers.