A unique combination of the ultrashort high-energy pulsed laser system with exceptional beam quality and a novel Diffractive Optical Element (DOE) enables simultaneous production of 2601 spots organized in the square-shaped 1 × 1 mm matrix in less than 0.01 ms. By adjusting the laser and processing parameters each spot can contain Laser Induced Periodic Surface Structures (LIPSS, ripples), including high-spatial frequency LIPSS (HFSL) and low-spatial frequency LIPSS (LSFL). DOE placed before galvanometric scanner allows easy integration and stitching of the pattern over larger areas. In addition, the LIPSS formation was monitored for the first time using fast infrared radiometry for verification of real-time quality control possibilities. During the LIPSS fabrication, solidification plateaus were observed after each laser pulse, which enables process control by monitoring heat accumulation or plateau length using a new signal derivation approach. Analysis of solidification plateaus after each laser pulse enabled dynamic calibration of the measurement. Heat accumulation temperatures from 200 to 1000 °C were observed from measurement and compared to the theoretical model. The temperature measurements revealed interesting changes in the physics of the laser ablation process. Moreover, the highest throughput on the area of 40 × 40 mm reached 1910 cm2/min, which is the highest demonstrated throughput of LIPSS nanostructuring, to the best of our knowledge. Thus, showing great potential for the efficient production of LIPSS-based functional surfaces which can be used to improve surface mechanical, biological or optical properties.

Growing demand for superhydrophobic surfaces in recent years is associated to many attractive science and engineering applications including self-cleaning, anti-icing and anti-corrosive behaviours. Stainless steel type AISI 316L is one of the most versatile and widely used engineering material in industries. Inspired by the "lotus effect" nano/microstructures has been fabricated by direct laser writing method with nanosecond laser source using two ablation regimes. Primarily, microstructures were fabricated with a tightly focused beam and covered by nano-scale structures by defocused laser beam in the second fabrication step. However, freshly prepared laser patterned metal surface shows hydrophilic behaviour. The hydrophilic to superhydrophobic transformation takes several days or weeks by aging technique in atmospheric condition. In this study, the transition time has been drastically reduced by high vacuum processing technique. Wetting properties with respect to laser processing parameters and surface morphology were examined and found to be consistent for large droplet volumes.

For the first time, a dynamic beamshaping technology has been utilized for the efficient production of periodic nanostructures on top of AlTiN coating to enable dry machining without costly and environmentally hazardous cutting fluids. First, a variety of periodic nanostructures with periods in a range of 740-273 nm were produced utilizing different wavelengths. Additionally, beamshaping technology increased productivity by 4008% up to 105 cm 2 min −1 by shaping the Gaussian beam into a rectangular beam of 500 × 30 µm. To simulate the application load and resulting heat production during manufacturing, friction analysis was performed at room and elevated temperature to 500°C. The analysis revealed a significant reduction in the friction coefficientup to 27% and 19% at room temperature and 500°C, respectively. The combination of these results demonstrates that the proposed method can be scaled up for the mass production of functionalized machining tools for dry machining.

The surface structure of medical implants and their chemical state are extremely important for their lifetime and reliability. There are problems with the degradation of NiTi implants due to structural fatigue, localized tribo-corrosion, and inconsistent hemocompatibility. These issues potentially can be solved by surface texturing by controlled short laser pulse treatments with a multibeam approach explored in this study. One of the unique surface textures in nanoscale is represented by introducing laser induced periodic surface structures (LIPSS) into the implant surface. The LIPSS formation involves the excitation of surface plasmon polaritons and material surface reorganization. Ripples with periodicity less than 1 ?m along with the catalytic activity of oxide surface with "rutile nanohairs" can significantly reduce bacterial film adhesion while promoting surface endothelialization and hemocompatibility. The morphological texturing of the surface allows for tuning the wetting properties from extreme hydrophobicity to hydrophilicity. Reduction of friction and wear of material surfaces can be achieved by introducing textures that reduce the contact friction area. The geometry of the LIPSS and dimples maintains an adhesive film of liquid among moving parts. Short laser "beam-shaped" pulses were applied in this work to NiTi surfaces. The results indicate that LIPSS processing of NiTi surface with controlled height profiles and periodicity gives rise to chemisorbed hydrocarbon molecules on rutile oxide layer, which leads to super-hydrophobicity and a beneficial antibacterial effect. Ultrashort laser pulse micromachining does not affect the microstructure and martensitic phase transformation. The corrosion resistance of LIPSS textured NiTi surface is not degraded, and the process reduces friction area and maintains an adhesive film of liquid between the moving parts.

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