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脉冲纳秒激光辐照金属玻璃材料会在表面产生一种特殊的波纹形貌,波纹的波长和振幅由内至外逐渐减小。利用扫描电镜(SEM)和原子力显微镜(AFM)观测了一种Ti基金属玻璃Ti_(40)Zr_(25)Cu_(12)Ni_3Be_(20)(%,质量分数)被纳秒脉冲激光辐照后表面的波纹形貌。与Zr基和La金属玻璃的实验结果相比,Ti基金属玻璃表面波纹形貌具有更广的范围和更小的特征尺度。在实验观测基础上进行合理的假设来简化模型,假设波纹形貌是由于小振幅表面波在深水域不可压粘性液体中传播,并在传播过程中被凝固而形成的。考虑波群理论和等离子体与熔融液体相互作用的影响,对实验结果进行理论分析。理论分析表明波长短的波传播更快,凝固前波传播的距离更远,所以越靠近边缘波的波长越短,分析结果也可以解释Ti基金属玻璃表面波纹范围更广的原因。此外,激光辐照金属玻璃会电离产生等离子体,通过理论计算发现变化的等离子体速度、密度和粘性等条件也会影响波纹形貌的形成,不同等离子体条件对应不同的波数,亦可通过实验数据观测的波数值反推等离子体条件。
Pulse nanosecond laser irradiation of metallic glass material will produce a special surface morphology, the ripple wavelength and amplitude decreases gradually from the inside to the outside. The Ti (40) Zr_ (25) Cu_ (12) Ni_3Be_ (20) (%, mass fraction) Ti-based metallic glass was irradiated by nanosecond pulsed laser by scanning electron microscope (SEM) and atomic force microscope Corrugated surface appearance. Compared with the experimental results of Zr-based and La-based metallic glass, the surface morphology of the Ti-based metallic glass has a wider range and a smaller characteristic scale. Based on the experimental observations, reasonable assumptions are made to simplify the model. It is assumed that the corrugation morphology is due to small amplitude surface waves propagating in incompressible viscous liquids in the deepwater and solidifying during propagation. Considering the wave group theory and the interaction between plasma and molten liquid, the experimental results are analyzed theoretically. The theoretical analysis shows that the shorter wave propagates faster and the wave propagates farther before solidification. Therefore, the shorter the wavelength closer to the edge wave, the analysis result can also explain the reason why the surface of the Ti-based metallic glass has a wider range of ripple. In addition, laser irradiation of metal glass ionization plasma generated by theoretical calculations found that changes in the plasma velocity, density and viscosity and other conditions will also affect the formation of corrugated morphology, different plasma conditions corresponding to different wavenumbers, but also by experiment Wave number data inversion of the observed plasma conditions.