Continuous hot-dip zinc-coated twin-roll cast steel sheet of structural quality and high strength steel

Anisotropic plastic behavior of advanced high strength steel sheet of grade TRIP780 (Transformation Induced Plasticity) was investigated using three different yield functions, namely, the von Mises’s isotropic, Hill’s anisotropic (Hill’48), and Barlat’s anisotropic (Yld2000-2d) criterion. Uniaxial tensile and balanced biaxial test were conducted for the examined steel in order to characterize flow behavior and plastic anisotropy for different stress states. Especially, disk compression test was performed for obtaining balanced r-value. All these data were used to determine the anisotropic coefficients. As a result, yield stresses and r-values for different directions were calculated according to these yield criteria. The results were compared with experimental data. To verify the modelling accuracy, tensile tests of various notched samples were carried out and stress-strain distributions in the critical area were characterized. By this manner, the effect of stress triaxiality due to different notched shapes on the strain localization calculated by the investigated yield criteria could be studied.

Download Full-text

Effect of Processing Parameters on Microstructure and Properties of Continuously Cast Al-Mg Sheets

Materials Science Forum ◽

10.4028/www.scientific.net/msf.482.279 ◽

2005 ◽

Vol 482 ◽

pp. 279-282 ◽

Cited By ~ 1

Author(s):

Margarita Slámová ◽

P. Sláma ◽

Petr Homola ◽

Miroslav Karlík

Keyword(s):

High Strength ◽

Cost Effective ◽

Processing Parameters ◽

Direct Chill ◽

Continuously Cast ◽

Chill Cast ◽

Direct Chill Cast ◽

Twin Roll Cast ◽

Twin Roll ◽

Al Mg Alloys

Inner panels of modern ecological cars are nowadays manufactured from Al-Mg alloys. Continuously twin-roll cast sheets are a cost effective substitution for direct-chill cast sheets. The effect of composition and down-stream processing on sheet properties should be well understood in order to produce high quality products, which exhibit good formability and high strength. Finegrained microstructure and well-balanced texture are the necessary pre-requisites. Results of the investigation of twin-roll cast AlMg2Mn0.8 and AlMg3 alloys are reported. Sheets of 1.0 mm gauge were prepared using different processing routes. The route involving homogenisation results in grain coarsening and anisotropy, however, deep-drawing ability is affected only a little.

Download Full-text