Model based optimization of process parameters to produce large homogeneous areas of laser-induced periodic surface structures

Results of the work in the Laser4Fun project has been published as:

Marek Mezera and G.R.B.E. Römer. Model based optimization of process parameters to produce large homogeneous areas of laser-induced periodic surface structures, Opt. Express 27, 6012-6029 (2019); doi: 10.1364/OE.27.006012

Abstract

A model is presented, which allows to predict the (in)homogeneity of large areas covered with Laser-induced Periodic Surface Structures (LIPSS), based on the laser processing parameters (peak laser fluence and geometrical pulse-to-pulse overlap) and experimentally determined material properties. As such, the model allows to establish optimal processing conditions, given the material properties of the substrate to be processed. The model is experimentally validated over a large range of geometrical pulse-to-pulse overlap values and fluence levels on silicon using a picosecond laser source.

Links:

DOI: 10.1364/OE.27.006012

PhD degree awarded to Fotis Fraggelakis

On February 14th, Fotis Fraggelakis successfully defended his thesis and was awarded the degree of PhD.

The now dr. Fraggelakis, was an Early Stage Researcher (ESR) of the Laser4Fun project. He was the the first PhD-candidate from the project to defend his PhD-thesis. The public defense ceremony took place on February 14th  at the Institute d’Optique d’Aquitaine (IOA) in Talence (France). He was supervised by dr. Inka Manek-Hönninger and dr. John Lopez of the University of Bordeaux, carried out most of his work at Alphanov under the supervision of dr. Rainer Kling of Alphanov, amongst others.

The PhD-defense committee consisted, among others, dr. Jörn Bonse of the Bundesanstalt für Materialforschung und -prüfung (BAM) in Berlin (Germany), prof. Antonio Ancona of the Consiglio Nazionale delle Ricerche (CNR), Istituto di Fotonica (IFN) of the University of Bari (Italy), and prof. Gert-willem Römer of the Chair of Laser Processing of the University of Twente (The Netherlands).

Fraggelakis2019.02.14-03XS

Fraggelakis2019.02.14-02XS

Fraggelakis2019.02.14-01XS

PhD defense ceremony Fotis Fraggelakis on Feb. 14th 2019

fotis.fraggelakisFotis Fraggelakis, an Early Stage Researcher (ESR), will be the first PhD-candidate from the Laser4Fun project to defend his PhD-thesis. The public defense ceremony will take place on February 14th , 2019 at 9:30 am, in The amphitheater of IOA, the Institute d’Optique d’Aquitaine (IOA) at the Rue François Mitterrand 33400 Talence (France). Supervised by dr. Inka Manek-Hönninger and dr. John Lopez of the University of Bordeaux, carried out most of his work at Alphanov under the supervision of dr. Rainer Kling of Alphanov, amongst others. Below is an English and French summary of the work and results of Fotis.

English summary

Current industrial markets demand highly value-added products offering new features at a low-cost. Among the most desired functionalities are, surface colouring and blackenning, anti-icing, anti-biofouling, wear reduction and anti-reflectivity. Functional textures found in nature indicate that those properties can be enable by textures in the micro and nanoscale. Laser surface processing holds a virtually endless potential in mimicking bio inspired textures by modifying surface morphology and chemistry. We investigate several techniques to achieve controlled laser structuring in the submicron regime such as polarization control and double pulse irradiation. Valuable data were provided both in the surface functionalization, in understanding and controlling of laser induced structuring and in upscaling a lab developed process. We believe that our results open the way for laser texturing exploitation in everyday applications exploiting up to date laser sources and positioning systems.

French summary

L’Industrie actuelle demande des produits à haute valeur ajoutée offrant des nouvelles fonctions à moindre coût telles que la coloration ou le noircissement de surface, la réduction des frottements, la génération de surface antiréflexion, antibactérienne, superhydrophobe ou anti-icing. Les surfaces fonctionnelles présentes dans la nature nous indiquent que ces propriétés uniques ne sont possibles par des texturations de surface à l’échelle micro et nanométrique adéquates. La technologie laser révolutionne le champ des possibles et permet de reproduire ces fonctions inspirées du monde du vivant en modifiant la morphologie et la chimie de surface. Nous avons étudié plusieurs techniques de texturation de surface par laser femtoseconde en jouant sur la polarisation et l’irradiation en double impulsion. Ces travaux de recherche apportent une contribution significative dans la compréhension des mécanismes et dans la capacité à produire de telles texturations sur des grandes surfaces

Mechanical durability of hydrophobic surfaces fabricated by injection moulding of laser-induced textures

Results of the work in the Laser4Fun project has been published as:

J.-M. Romano, M. Gulcur, A. Garcia-Giron, E. Martinez-Solanas, B.R. Whiteside and S.S. Dimov. Mechanical durability of hydrophobic surfaces fabricated by injection moulding of laser-induced textures. Applied Surface Science 476 (2019) 850-860

Abstract

The paper reports an investigation on the mechanical durability of textured thermoplastic surfaces together with their respective wetting properties. A range of laser-induced topographies with different aspect ratios from micro to nanoscale were fabricated on tool steel inserts using an ultrashort pulsed near infrared laser. Then, through micro-injection moulding the topographies were replicated onto polypropylene surfaces and their durability was studied systematically. In particular, the evolution of topographies on textured thermoplastic surfaces together with their wetting properties were investigated after undergoing a controlled mechanical abrasion, i.e. reciprocating dry and wet cleaning cycles. The obtained empirical data was used both to study the effects of cleaning cycles and also to identify cleaning procedures with a minimal impact on textured thermoplastic surfaces and their respective wetting properties. In addition, the use of 3D areal parameters that are standardised and could be obtained readily with any state-of-the-art surface characterisation system are discussed for monitoring the surfaces’ functional response.

Link(s)

Controlling 2D laser nano structuring over large area with double femtosecond pulses

Results of the work in the Laser4Fun project has been published as:

F. Fraggelakis, G. Mincuzzi, J. Lopez, I. Manek-Hönninger and R. Kling. Controlling 2D laser nano structuring over large area with double femtosecond pulses. Applied Surface Science, November 2018

Abstract

Laser surface texturing is an established way to introduce surface functionalities on solid surfaces. By means of femtosecond laser sources, it’s possible to texture a variety of solids such as metals, semiconductors and transparent materials, introducing features of different symmetry and size. Fabrication of laser induced periodic surface structure (LIPSS) which typically range in the near-submicron length scale can lead to strong modifications of surface wetting, tribological and optical properties. Controlling LIPSS morphology could enable us to mimic functional textures found in nature, introducing functionalities such as antireflectivity and bactericidity. Several works demonstrate the impact of polarization control and double-pulse irradiation on determining texture symmetry and size. Here we present a comprehensive study on controlling laser induced structures by double femtosecond pulse irradiation. The effect of pulse polarization and interpulse delay is elucidated and the generation of novel 2D surface morphologies is reported. A plausible interpretation of the structure formation mechanism is proposed in the frame of non-linear convection flow. A high average power industrial femtosecond laser source with a pulse duration of 350 fs operating at high repetition rate was employed for the experiments. Large areas were processed by combining different 2D morphologies generating a holographic pattern. We believe that our results provide a novel insight in controlling laser induced submicron morphology. Moreover, the presented surface texturing process is scalable in terms of processed area and cycle time and fully compatible with high repetition rates, demonstrating for the first time the feasibility to introduce double-pulse processing in an industrial environment.

Link(s)

Laser-Induced Periodic Surface Structures (LIPSS) on Polymers Processed with Picosecond Laser Pulses

Results of the work in the Laser4Fun project has been published as:

Marek Mezera, Martin van Drongelen and G.R.B.E. Römer. Laser-Induced Periodic Surface Structures (LIPSS) on Polymers Processed with Picosecond Laser Pulses, Journal of Laser Micro/Nanoengineering  Vol. 13, No. 2, 2018; doi: 10.2961/jlmn.2018.02.0010

Abstract

Based on a literature review, it was concluded that Laser-induced Periodic Surface Structures (LIPSS) on polymers are produced when applying laser sources operating either in the ultraviolet wavelength and nanosecond pulse duration, or radiation of wavelengths ranging from 265nm to 1045nm and pulse durations in the femtosecond regime. LIPSS were not reported when using pico-second laser sources. The purpose of this paper is to study whether (and if so which) LIPSS form on polymers when picosecond pulsed laser source is applied. Low Spatial Frequency LIPSS (LSFL) and High Spatial Frequency LIPSS (HSFL) have been obtained on polycarbonate and on polystyrene when applying picosecond laser pulses at a wavelength of 343nm on single spots and on processed lines. When using a wavelength of 515nm, LSFL and HSFL have been produced only on polycar-bonate, but also led to porosity of the structured area.

Links:

DOI: 10.2961/jlmn.2018.02.0010

Annual Technical Board and Supervisory Board Meeting in Bari, Italy (2018)

The 2018 Technical Board (TB) meeting and Supervisory Board (SB) meeting of the Laser4Fun project took place on October 4 and 5 in Bari, Italy. The meeting was hosted by prof. Antonio Ancona of IFN-CNR, Istituto di Fotonica e Nanotecnologie, Bari, Italy. The TB & SB discussed the progress of the project, results, management and reporting issues, as well as communication and dissemination topics. Also all Early Stage Researchers (ESRs) presented their progress and results to the SB. We were happy to conclude the project is well on track.

Technical Board (TB) meeting and Supervisory Board (SB) and all ESRs during the annual progress meeting in Bari, Italy.
Technical Board (TB) and Supervisory Board (SB) and all ESRs during the annual progress meeting in Bari, Italy.

Summer School on Laser Micro/Nanostructuring and Surface Tribology 2018

The 3rd Laser4Fun international Summer School took place from October 1st to 5th and was hosted by prof. Antonio Ancona of the IFN-CNR, Istituto di Fotonica e Nanotecnologie in Bari, Italy. The participants of the summer school were “fully-immersed” into the world of Laser Micro/Nanostructuring and Surface Tribology. Lectures and presentations by academic experts and of the participants alternated, with ample time for discussions. Topics included, but were not limited to:

  • Contact mechanics of elastic bodies, by dr. Ing. Carmine Putignano (Politecnico di Bari, Department of Mechanics, Mathematics and Management)
  • Universal lab-on-a-chip platform for complex, perfused 3D tissues generated by 3D printing – opportunities and perspectives for laser technology, by dr. Ing. Udo Klotzbach (Fraunhofer-Institut Material and Beam Technology IWS Dresden, Business Unit Manager Microtechnology)
  • Management of innovative project at Bosch: LST case study, by ing. Antonio Grimaldi and Ing. Renato Giannoccaro (Robert Bosch Group – Centro Studi Componenti per Veicoli s.p.a)
  • Cross Cultural Competences through cooperation and autonomy. Learning organization: higher education management and research administration, by dr.ssa Mariapia Circella (Physics Department, University of Bari)
  • Femtosecond laser micro-fabrication of polymeric lab-on-chip for advanced and mini-invasive diagnostics, by Udith K. Vadakkum Vadukkal (University of Bari, Italy)
  • Femtosecond laser bursts induced micro and nanostructuring on steel surface, by Giuseppe Giannuzzi (Università di Bari, Italy)
  • Contact mechanics of viscoelastic bodies, by prof. Ing. Giuseppe Carbone (PoliBa- Department of Mechanics, Mathematics and Management)
  • University of 21st century: threats and opportunities. Organizational chart: practical experiences, by dr.ssa Mariapia Circella (Physics Department, University of Bari)
Prticipants of the international School on Laser Micro/Nanostructuring and Surface Tribology 1st-5th October 2018, Bari, Italy
Prticipants of the international School on Laser Micro/Nanostructuring and Surface Tribology
1st-5th October 2018, Bari, Italy