Effect of fluence and ambient environment on the surface and structural modification of femtosecond laser irradiated Ti  

作　　者：Umm-i-Kalsoom Shazia Bashir Nisar Ali M Shahid Rafique Wolfgang Husinsky Chandra S R Nathala Sergey V Makarov Narjis Begum 

机构地区：[1]Institute for Applied Physics,Vienna University of Technology,Vienna,Austria [2]Centre for Advanced Studies in Physics,GC University Lahore,Pakistan [3]Department of Physics,The University of Lahore,Pala'stan [4]Department of Basic Sciences and Humanities,University of Engineering and Technology Fasalabad,Pakistan [5]Department of Physics,University of Engineering and Technology Lahore,Pakistan [6]P.N.Lebedev Physics Institute RAS,Moscow,Russia [7]Department of Physics,COMSATS Institute of Information and Technology,Islamabad,Pakistan

出　　处：《Chinese Physics B》2016年第1期789-795,共7页中国物理B（英文版）

基　　金：supported bysterreichische Forschungsfdergesellschaft(FFG)(Grant No.834325)

摘　　要：Under certain conditions, ultrafast pulsed laser interaction with matter leads to the formation of self-organized conical as well as periodic surface structures （commonly reffered to as, laser induced periodic surface structures, LIPSS）. The purpose of the present investigations is to explore the effect of fsec laser fluence and ambient environments （Vacuum ＆ 02） on the formation of LIPSS and conical structures on the Ti surface. The surface morphology was investigated by scanning electron microscope （SEM）. The ablation threshold with single and multiple （N = 100） shots and the existence of an incubation effect was demonstrated by SEM investigations for both the vacuum and the 02 environment. The phase analysis and chemical composition of the exposed targets were performed by x-ray diffraction （XRD） and energy dispersive x-ray spectroscopy （EDS）, respectively. SEM investigations reveal the formation of LIPSS （nano ＆ micro）. FFT d-spacing calculations illustrate the dependence of periodicity on the fluence and ambient environment. The periodicity of nano-scale LIPSS is higher in the case of irradiation under vacuum conditions as compared to 02. Furthermore, the 02 environment reduces the ablation threshold. XRD data reveal that for the 02 environment, new phases （oxides of Ti） are formed. EDS analysis exhibits that after irradiation under vacuum conditions, the percentage of impurity element （A1） is reduced. The irradiation in the 02 environment results in 15% atomic diffusion of oxygen.Under certain conditions, ultrafast pulsed laser interaction with matter leads to the formation of self-organized conical as well as periodic surface structures （commonly reffered to as, laser induced periodic surface structures, LIPSS）. The purpose of the present investigations is to explore the effect of fsec laser fluence and ambient environments （Vacuum ＆ 02） on the formation of LIPSS and conical structures on the Ti surface. The surface morphology was investigated by scanning electron microscope （SEM）. The ablation threshold with single and multiple （N = 100） shots and the existence of an incubation effect was demonstrated by SEM investigations for both the vacuum and the 02 environment. The phase analysis and chemical composition of the exposed targets were performed by x-ray diffraction （XRD） and energy dispersive x-ray spectroscopy （EDS）, respectively. SEM investigations reveal the formation of LIPSS （nano ＆ micro）. FFT d-spacing calculations illustrate the dependence of periodicity on the fluence and ambient environment. The periodicity of nano-scale LIPSS is higher in the case of irradiation under vacuum conditions as compared to 02. Furthermore, the 02 environment reduces the ablation threshold. XRD data reveal that for the 02 environment, new phases （oxides of Ti） are formed. EDS analysis exhibits that after irradiation under vacuum conditions, the percentage of impurity element （A1） is reduced. The irradiation in the 02 environment results in 15% atomic diffusion of oxygen.

关 键 词：LIPSS ablation threshold incubation coefficient structural modification 

分 类 号：O437[机械工程—光学工程]