Analysis of Large Inclusions in Q195 Steel

Aimed at the Q195 steel strip inclusion defects in a steel mill, using tracer analysis make system analysis to casting of large inclusions content. Large inclusions in casting containing ladle slag accounted for about 39% of the total number of test, containing tundish covering agent accounts for about 42.2%, while containing protection slag accounted for 45%. Shows that large inclusions in the billet is mainly comes from the crystallizer mold powder entrapment, secondly is the tundish slag and the ladle slag powder entrapment. When transient casting large inclusions content is steady casting several times, increasing the stability of operation on transient casting, controlling the stability of cast-on and ladle changing, stabilizing the liquid level of tundish and mould can improve the quality of the steel.

Analysis of Micro Inclusions in Q195 Steel

Aimed at the Q195 steel production process in a steel mill, using tracer analysis make system analysis to the process of production and microscopic inclusions content. In the steady casting average T[O] is 117.22ppm, [N] is 22.6ppm, micro inclusions average content is 11.96/mm2, while the average T[O] and [N] in transient casting billet is 161.93ppm and 30.49ppm, micro inclusions averaged content is 16.068/mm2. The total oxygen content in steel on the high side, should strengthen deoxidization. Argon stirring strength is too large, inclusions in casting slab containing tracer element, illustrate the ladle slag, tundish slag, mould protection slag are forming pollution on billet, should reduce the influence of transient casting on the steel quality.

The Influence of Transient Casting on Inclusions in Steel

Influence on the transient casting of large inclusions in steel were studied by means of tracer method, kinds of steel large inclusions content in transient casting is 1.5 times ~8 times to the steady casting, large inclusions principal from crystallizer mold powder entrapment, then the tundish slag and the ladle slag. Slag and refractory has a certain influence on high quality steel. Reducing fluctuations caused by transient casting is the key to improve the quality of the steel.