Nanopattern replication of complex structures by plastic injection is a challenge that requires simulations to define the right processing parameters. Previous work managed to simulate replication for single cavities in 2D and 3D, showing high performance requirements of CPU to simulate periodic trenches in 2D. This paper presents two ways to approach the simulation of replication of complex 3D hydrophobic surfaces. The first approach is based on previous CFD Ansys Fluent and compared to FE based CFD Polyflow software for the analysis of laminar flows typical in polymer processing and glass forming as well as other applications. The results showed that Polyflow was able to reduce computing time from 72 h to only 5 min as desired in the project. Furthermore, simulations carried out with Polyflow showed that higher injection and mold temperature lead to better replication of hydrophobicity in agreement with the experiments. Polyflow simulations are proved to be a good tool to define process parameters such as temperature and cycle times for nanopattern replication.

Surface textures such as laser-induced periodic surface structures (LIPSS) are of great interest to obtain industrial nanopatterns. In this work, plain uncoated 1.2344 steel with and without Chromium Nitride (CrN) and CrN plus diamond-like carbon (DLC) coatings were used in experiments. The laser texturing variables studied were the laser speed (3000–4000 mm/s) and the distance between laser lines (1–10 microns). These structures were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM) to obtain an overview of the roughness and to analyze the heights of the obtained structures. A two-dimension fast Fourier transform (2D-FFT) of the SEM images and its characteristic frequencies was used to assess the periodicity of the textured surfaces and thus quantify the far-range order. The speed of laser depth ablation is related to the laser energy density for each coating and textures are qualified using the FFT approach.