纳秒激光瞬蒸破胞及激光顺切微纳米木纤维成型机理研究

Paper-making and fiber-using industry has been plagued by how to strip fiber to micron level.Traditional hot grinding method can only grind wood fiber to millimeter level, and micro-level wood fiber cutting with diamond tools costs a lot.It also can be processed with chemical methods,but the acid-base raffinate remains on it could low its industrial value greatly. The process simulates the laser heating head and the laser cutting head with cell lysis texture trend, and heats the saturated water inside the wood surface cells instantaneously with nanosecond high density laser. The vapor in the cell cavity will expand and be pressurized because of instant gasification, which makes the cell cavity burst and covers the wood surface with micro-nano filamentous burrs. And then slice the wood to long micro-nano filaments along the filaments texture with the laser cutting heads which are arranged along the direction of the grain of the wood. And then verifies simulation results, designs and creates experimental devices of the CNC micro-nano slicing and nanosecond lacer flash lysing, and provides a physical method which can process micro-nano wood fiber filament pollution-freely by computer based experiment.

纤维微纳米剥离一直困扰造纸和木纤维利用行业，传统热磨只能加工到毫米级，金刚石刀具能达到微米级，但成本太高。化学法的酸碱残液遗留大幅度降低了其工业价值。以细胞裂解纹理走向仿真纳秒激光加热头和切削头，模拟纳秒高密度激光瞬间加热木材表面细胞内的饱和水，仿真瞬间气化引起腔内水膨胀和压升，使细胞腔爆裂，形成木材表面遍布微纳米细丝状毛刺。再仿真顺纹方向布置的纳秒激光切削头，沿细丝纹理走向进行顺纹激光剥离刨切，模拟形成微纳米木纤维长细丝。用计算机模拟验证仿真结果，设计数控激光微纳米刨切和纳秒激光瞬蒸爆裂胞壁实验台，提供物理法无污染加工的微纳米木纤维细丝仿真模拟方法。

木纤维是一种天然、可再生的纤维材料，纤维微纳米剥离一直困扰造纸和木纤维利用行业，传统热磨只能加工到毫米级，金刚石刀具能达到微米级，但成本太高。化学法的酸碱残液遗留将大幅度降低该法工业价值。本项目将纳秒激光刨切技术融入到微纳米木纤维加工中，提出一种新型纳秒激光刨切微纳米木纤维的加工方法，利用纳秒激光加热爆破木材表面细胞，导致纤维丝崩开；再沿细胞长度方向用纳秒激光束切割纤维丝，得到微纳米级别的木纤维。这种方法不仅突破了木材物理加工的瓶颈，一方面克服了刀具切削加工的刀尖半径限制，另一方面解决了热磨机加工的大功耗问题，而且也避免了化学方法加工造成的环境污染。一年来，项目研究进展顺利，在微纳米木纤维细胞微观形貌数学描述理论研究的基础上，建立纤维细胞爆裂胞壁微观结构仿真模型。设计研发了数控激光微纳米刨切和纳秒激光瞬蒸爆裂胞壁实验台，进行纳秒激光瞬蒸破胞顺纹切割微纳米木纤维实验和相关理论研究与计算机模拟仿真研究。设计开发了纳秒激光微纳米加工微米细丝仿真软件系统，提供物理法无污染加工的微纳米木纤维细丝仿真模拟方法。项目申请发明专利2项、软件著作权1项，发表学术论文9篇。