The formation of highly-twinned ultrafine austenite on a cold rolled AISI 316L steel induced by low energy high current pulsed electron beam (LEHCPEB) treatment has been investigated. It is shown that rapid phase transformation, recrystallization and recovery can be achieved simultaneously through pulsed electron beam treatments under heating mode without melting the surface. The extremely fast thermo-mechanical cycles induced by the LEHCPEB account for the surface austenization and the formation of ultrafine twins. The results demonstrated that pre-deformation combined with LEHCPEB treatment under heating mode can be used to create ultrafine microstructures with special boundary characteristics in the surface layer. (C) 2012 Elsevier B. V. All rights reserved.