Formation of Surface Depression during Continuous Casting of High-Al TRIP Steel
AbstractHigh aluminum transformation-induced plasticity (TRIP) steels offer a unique combination of high tensile strength and ductility, high impact energy absorption and good formability. The surface of the slab is prone to depressions and longitudinal cracks during continuous casting due to the high Al content in steels. Surface depressions of the 1.35 wt.% Al-TRIP steel slab in a steel works were investigated by scanning electronic microscopy (SEM) and mold fluxes with different Al2O3/SiO2 ratios were researched by thermodynamic calculations and high-temperature static balance experiments. The results show that some micro-cracks were distributed along the grain boundary in the surface depression of the slab. Inclusions containing K and Na, which were probably from mold flux, were found in the depression samples. Meanwhile, the components of reactive mold flux showed significant variation in their chemical composition during the continuous casting process of the Al-TRIP steel. A large number of depressions and irregular oscillation marks on the Al-TRIP steel slab surface were generated due to serious deterioration in the physical properties of the mold flux. Since the TRIP steel is a typical hypo-peritectic steel, the overly large thermal contraction and volume contraction during initial solidification is the intrinsic cause of surface depression. The change of mold flux properties during casting aggravates the formation of depressions. View Full-Text
Share & Cite This Article
Cui, H.; Zhang, K.; Wang, Z.; Chen, B.; Liu, B.; Qing, J.; Li, Z. Formation of Surface Depression during Continuous Casting of High-Al TRIP Steel. Metals 2019, 9, 204.
Cui H, Zhang K, Wang Z, Chen B, Liu B, Qing J, Li Z. Formation of Surface Depression during Continuous Casting of High-Al TRIP Steel. Metals. 2019; 9(2):204.Chicago/Turabian Style
Cui, Heng; Zhang, Kaitian; Wang, Zheng; Chen, Bin; Liu, Baisong; Qing, Jing; Li, Zhijun. 2019. "Formation of Surface Depression during Continuous Casting of High-Al TRIP Steel." Metals 9, no. 2: 204.
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.