Research on the friction stir welding of Titanium Grade 1 R. Kosturek, M. Wachowski, T. Ślęzak, L. Śnieżek, J. Mierzyński and U. Sobczak MATEC Web Conf., 242 (2018) 01006 Published online: 05 December 2018 DOI: 10.1051/matecconf/201824201006