TY - CONF A1 - Falkenreck, Thora A1 - Kromm, Arne A1 - Böllinghaus, Thomas T1 - Investigation of Physically Simulated Weld HAZ and CCT-diagram of HSLA steel N2 - The phase transformation under various cooling rates and in different HAZ regions for high strength armour steel was analysed by dilatometry. To develop a Continuous Colling Transformation (CCT) diagram, the samples were heated up to a peak temperature of 1250 °C to achieve a coarse grained microstructure and then cooled down with a cooling time t8/5 varying from 3 s to 240 s. Analysis of dilatation curves revealed the austenite decomposition process, during which transformation temperatures were determined. The results showed martensitic transformations for all welding relevant cooling times. Furthermore, to analyse different heat affected subzones of the weld, the peak temperature was varied between 550 °C and 1250 °C at a constant cooling time t8/5 of 6 s. The simulated coarse grained heat affected zone (CGHAZ) and fine grained heat affected zone (FGHAZ) showed only martensitic transformations with transformation temperatures below 400 °C. The steel exhibited an inhomogeneous hardness with hardening in the CGHAZ and FGHAZ and softening in the intercritical and subcritical HAZ. The physically simulated microstructure was validated by a real hybrid laser-arc weld microstructure. T2 - IIW Intermediate meeting, IX-L CY - Trollhättan, Sweden DA - 06.03.2017 KW - Dilatometry KW - High strength stells KW - CCT diagrams KW - Heat affected zone PY - 2017 AN - OPUS4-39437 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -