-
摘要: 热传导规律的研究在激光诱导薄膜材料改性等应用中有着重要的作用，本文针对二氧化碳激光器辐照下的二氧化钛（TiO2）薄膜表面的热效应进行了理论仿真和实验研究。首先，对具有粗糙上表面的TiO2薄膜，利用有限元法构建了连续激光作用下的TiO2薄膜的立体模型并得到了其三维温度场分布。然后使用CO2激光器进行辐照实验，分析了辐照时间和功率等参数对TiO2薄膜形貌、晶相以及颜色的影响。仿真表明，连续激光辐照下TiO2薄膜的瞬态温度场呈高斯分布，且与激光功率、光斑半径、辐照时间等因素有关。当表面温度小于分解温度时，薄膜上表面最大平均温度与激光功率满足线性关系，与光斑半径满足ExpAssoc非线性关系。实验结果表明，激光辐照引起TiO2薄膜材料表面粗糙度降低且颜色变化。激光功率过小或辐照时间过短会导致有效作用面积小且不均匀，反之会产生热形变。结合仿真和实验可知使用功率为6 W，半径为3 mm的连续激光辐照TiO2薄膜10 s时取得的处理效果最优。Abstract: The laws of heat conduction play an important role in the application of laser-induced film material modification. In this paper, the thermal effects of titanium dioxide(TiO2) film surfaces irradiated by a carbon dioxide laser was studied theoretically and experimentally. Firstly, a three-dimensional model of titanium dioxide thin film with a rough surface was constructed using a finite element method and their three-dimensional temperature distribution were calculated. Then, the TiO2 thin films were irradiated by a CO2 laser and the effects of irradiation time, power on the morphology, crystal phases and color were analyzed. Simulation results show that the transient temperature field of titanium dioxide irradiated by a CW laser is a Gaussian distribution, which is related to laser power, spot radius, irradiation time and other factors. When the surface temperature is less than the decomposition temperature, the maximum average surface temperature of the film meets the linear relationship with the laser power, and the ExpAssoc nonlinear relationship is satisfied with laser spot radius. Experimental results show that because of laser irradiation, the roughness of TiO2 thin film decreased and the color of the film changed. Small laser power or short irradiation time leads to small and uneven effective area, on the contrary thermal deformation will occur. Combined with the simulation and experiment results, it is found that the best treatment effect can be obtained when irradiating TiO2 thin film 10 seconds with a laser with a power of 6 W and a radius of 3 mm.
-
Key words:
- continuous laser /
- titanium dioxide film /
- heat transfer rule
-
图 3 0.5、2.5、5、10 s时的上表面等温线及热量传导方向示意图
Figure 3. Schematic diagram of isotherm and heat conduction direction on the upper surface at 0.5, 2.5, 5 and 10 s
图 4 不同激光功率下上表面平均温度-时间曲线
Figure 4. Average temperature-time curves of upper surface under different laser powers
图 5 激光功率与上表面最大平均温度的线性拟合
Figure 5. Linear fitting of laser power and maximum mean temperature on the upper surface
图 6 不同激光功率下上表面中心线上温度分布曲线
Figure 6. Temperature distribution curves of upper surface centerline under different laser powers
图 7 不同激光光斑半径下上表面平均温度-时间曲线
Figure 7. Average temperature-time curves of upper surface under different laser radius
图 8 激光功率与上表面最大平均温度的线性拟合
Figure 8. Linear fitting of laser power and maximum mean temperature on the upper surface
图 9 不同光斑半径下上表面中心线温度分布曲线
Figure 9. Temperature distribution curves of upper surface centerline under different laser radius
图 12 不同激光功率下的样品表面显微图
Figure 12. Micrographs of sample surface under different laser powers
图 13 不同激光功率下样品的X射线衍射图谱
Figure 13. X-ray diffraction spectra of sample with different laser powers
图 14 不同辐照时间下样品表面显微图
Figure 14. Micrographs of sample surface under different irradiation times
图 15 不同激光辐照时间下样品的X射线衍射图谱
Figure 15. X-ray diffraction spectra of sample under different laser irradiation times
表 1 特性参数
Table 1. Characteristic parameters
Parameters Abbr. Unit Value Constant pressure heat capacity C J·Kg-1·K-1 710 Thickness d mm 0.1 Length l mm 3.35 Laser radius a mm 3 Thermal conductivity k W·m-1· K-1 8.4 Absorption coefficient α m-1 1 800 Scattering coefficient σs m-1 2.647 Density ρ kg·m-3 3 313 Thermal radiation rate ε 1 0.1 Surface heat transfer coefficient h W·cm-1· K-1 156 
下载: 导出CSV
表 2 高斯函数拟合公式及相关系数拟合参数
Table 2. Gauss functions and their fitting parameters
Laser power/W Equation R2 a 3 y=317.5087+34.03*exp{-2*[(x+1.9595e-4)/5.0947]2} 0.999 1 b 6 y=341.8283+68.0073*exp{-2*[(x+1.9607e-4)/5.0956]2} 0.999 1 c 9 y=366.8283+101.9044*exp{-2*[(x+1.9626e-4)/5.0969]2} 0.999 1 d 12 y=390.3105+135.7004*exp{-2*[(x+1.9633e-4)/5.0986]2} 0.999 1 e 15 y=414.45+169.3716*exp{-2*[(x+1.9626e-4)/5.1007]2} 0.999 1 f 18 y=438.5033+202.8924*exp{-2[(x+1.9634e-4)/5.1032]2} 0.999 1
下载: 导出CSV
表 3 ExpAssoc函数及Allometricl函数形式及相应拟合参数
Table 3. ExpAssoc function, Allometricl function and their fitting parameters
Function name Equation R2 ExpAssoc y=188.785 5-1 525.934 4*[1-exp(-x/1.130 9)] 0.999 3 Allometricl y=983.785 4*x^(-669 9) 0.997 3
下载: 导出CSV
表 4 拟合参数
Table 4. Fitting parameters
Laser radius/mm Equation R2 a 1 y=356.5106+45.9932*exp{-2*[(x-7.6126e-4)/5.5986]2} 0.999 1 b 2 y=347.7367+630.6741*exp{-2*[(x+5.7232e-5)/2.8963]2} 0.999 2 c 3 y=356.8013+249.8764*exp{-2*[(x+0.0013)/4.2904]2} 0.999 4 d 4 y=366.0817+101.9233*exp{-2*[(x+2.1173e-4)/5.0977]2} 0.999 1
下载: 导出CSV
-
[1] GARESO P L, SAMPE N, PALENTEK V, et al.. Influence of annealing on Fe-doped TiO2 powders using co-precipitation technique[J]. AIP Conference Proceedings, 2017, 1801(1):020002. http://cn.bing.com/academic/profile?id=0f67a5130299ac54c134a499e908cdb3&encoded=0&v=paper_preview&mkt=zh-cn [2] SPINELLI P, MACCO B, VERSCHUUREN M A, et al.. Al2O3/TiO2 nano-pattern antireflection coating with ultralow surface recombination[J]. Applied Physics Letters, 2013, 102(23):233902. doi: 10.1063/1.4810970 [3] CHOU J C, YANG H Y, CHEN CH W. Glucose biosensor of ruthenium-doped TiO2 sensing electrode by co-sputtering system[J]. Microelectronics Reliability, 2010, 50(5):753-756. doi: 10.1016/j.microrel.2010.01.025 [4] MIRGHANI M, AL-MUBAIYEDH U A, NASSER M S, et al.. Experimental study and modeling of photocatalytic reduction of Pb2+ by WO3/TiO2 nanoparticles[J]. Separation and Purification Technology, 2015, 141:285-293. doi: 10.1016/j.seppur.2014.12.006 [5] YAMAMOTO A, MIZUNO Y, TERAMURA K, et al.. Visible-light-assisted selective catalytic reduction of NO with NH3 on porphyrin derivative-modified TiO2 photocatalysts[J]. Catalysis Science & Technology, 2015, 5(1):556-561. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=f03584ef1a2b187e89e7ba95fcfc58f9 [6] HVHM S, ROSENFELD A, KRVGER J, et al.. Laser-induced periodic surface structures on zinc oxide crystals upon two-colour femtosecond double-pulse irradiation[J]. Physica Scripta, 2017, 92(3):034003. doi: 10.1088/1402-4896/aa5578 [7] 袁志刚, 李亚国, 陈贤华, 等.光学元件改性处理对激光损伤阈值的影响[J].光学 精密工程, 2016, 24(12):2956-2961. http://d.old.wanfangdata.com.cn/Periodical/gxjmgc201612010YUAN ZH G, LI Y G, CHEN X H, et al.. Effect of chemical modification technology laser damage threshold of fused silica optical elements[J]. Opt. Precision Eng., 2016, 24(12):2956-2961.(in Chinese) http://d.old.wanfangdata.com.cn/Periodical/gxjmgc201612010 [8] TRTICA M S, GAKOVIC B M, RADAK B B, et al.. Material surface modification by ns, ps and fs laser pulses[J]. Opt. Precision Eng., 2011, 19(2):221-227. doi: 10.3788/OPE. [9] 周海娇, 孙文军, 刘中洋.脉冲激光辐照GaAs材料热效应研究[J].光子学报, 2014, 43(11):21-25. http://d.old.wanfangdata.com.cn/Periodical/gzxb201411005ZHOU H J, SUN W J, LIU ZH Y, et al.. Research of nonlinear absorption effect of pulse laser irradiation for GaAs[J]. Acta Optica Sinica, 2014, 43(11):21-25.(in Chinese) http://d.old.wanfangdata.com.cn/Periodical/gzxb201411005 [10] 王伟树.毫秒激光辐照半导体材料的热力效应数值模拟[D].长春: 长春理工大学, 2014. http://www.wanfangdata.com.cn/details/detail.do?_type=degree&id=Y2529054WANG W SH. Numerical simulation of thermal-mechanical effects during millisecond laser irradiate semiconductor materials[D]. Changchun: Changchun University of Science and Technology, 2014.(in Chinese). http://www.wanfangdata.com.cn/details/detail.do?_type=degree&id=Y2529054 [11] SAID-BACAR Z, LEROY Y, ANTONI F, et al.. Modeling of CW laser diode irradiation of amorphous silicon films[J]. Applied Surface Science, 2011, 257(12):5127-5131. doi: 10.1016/j.apsusc.2010.11.025 [12] 张宏伟, 任妮, 薛红涛, 等.聚酰亚胺基底金属薄膜激光刻蚀温度场分布[J].中国激光, 2016, 43(5):94-101. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=zgjg201605014ZHANG H W, REN N, XUE H T, et al.. Temperature distribution for laser etching of metal thin films on polyimide substrate[J]. Chinese Journal of Lasers, 2016, 43(5):94-101.(in Chinese) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=zgjg201605014 [13] 周维军, 袁永华, 桂元珍, 等.脉冲激光辐照TiO2/SiO2薄膜热效应研究[J].强激光与粒子束, 2007, 19(1):23-26. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=qjgylzs200701006ZHOU W J, YUAN Y H, GUI Y ZH, et al.. Thermal effect of TiO2/SiO2 film irradiated by pulse laser[J]. High Power Laser and Particle Beams, 2007, 19(1):23-26.(in Chinese) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=qjgylzs200701006 [14] 宋宏伟, 黄晨光.激光辐照诱导的热与力学效应[J].力学进展, 2016, 46(1):201610. http://d.old.wanfangdata.com.cn/Periodical/lxjz201601010SONG H W, HUANG CH G. Progress in thermal-mechantical effects induced by laser[J]. Advances in Mechanics, 2016, 46(1):201610.(in Chinese) http://d.old.wanfangdata.com.cn/Periodical/lxjz201601010 [15] HOSSAIN M M, CHOWDHURY M H. Heat transfer simulations for pulsed laser annealing of silicon thin film[C]. Proceedings of IEEE 56th International Midwest Symposium on Circuits and Systems, IEEE, 2013: 732-735. https://www.researchgate.net/publication/261308482_Heat_transfer_simulations_for_pulsed_laser_annealing_of_silicon_thin_film -
下载:
计量
- 文章访问数: 2220
- HTML全文浏览量: 813
- PDF下载量: 163
- 被引次数: 0
