Lubricant-free deep drawing using CO2 and N2 as volatile media injected through laser-drilled microholesEhsan Zahedi, Christoph Woerz, Gerd Reichardt, Georg Umlauf, Mathias Liewald, Jakob Barz, Rudolf Weber and Thomas GrafMATEC Web Conf., 190 (2018) 14007DOI: https://doi.org/10.1051/matecconf/201819014007