Effects of Cold Deformation and Annealing on Mechanical Properties, Microstructure and Precipitation State of a Ti-Nb AHSS

摘要

An advanced high-strength C-Mn-Cr-Ti-Nb steel sheet that was hot rolled at 900℃ finishing temperature and 500℃ coiling temperature was subjected to several thermo-mechanical processes simulating temper rolling, cold rolling, batch annealing and galvanizing. Tensile properties and microstructure were characterized for each condition. Transformation during annealing was detected by dilatation measurement. Selective precipitation characterization and quantification using TEM and utilizing the ICP method were also performed. Changes in the final mechanical properties were determined by the amount of cold deformation, recrystallization and precipitation.