What is the difference between Q235B and Q235B.F?
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I would like to ask all friends, can Q235B steel plate and Q235B.F steel plate replace each other? If not, according to the principle of replacing low with high, which steel is better? What are the applicable occasions of these two steel plates? Please give me your advice:handshake This post was last edited by Yang Zhanhui on 2009-4-19 08:48 ]
Boiling steel is steel with incomplete deoxidation. During pouring, the molten steel boils (gas escapes) in the steel ingot mold. After the steel ingot solidifies, honeycomb bubbles are distributed in the steel ingot. During the rolling process, the bubble cavities will be bonded together. The characteristic of this type of steel is that the silicon content in the steel is very low, and it is usually injected into steel ingots with a small top and a large bottom without an insulation cap. The advantages are high steel yield, low production cost, good surface quality and deep drawing performance. The disadvantage is that steel has many impurities and large component segregation, so its performance is uneven. 235B can be used instead of 235BF
Q235 Ordinary carbon structural steel-Plain plate is a kind of steel material. Q represents the yield of this material, and the following 235 refers to the yield value of this material, which is around 235. And as the thickness of the material increases, its yield value decreases. Q235A，Q235B，Q235C，Q235D。 This is a distinction between levels, and what it represents is mainly that the temperature of the impact is different! The difference between A, B, C, and D refers to the difference in impact temperature in their performance. respectively: Q235A level, does not do impact ； Q235B grade, is a 20 degree normal temperature impact ； Q235C level, 0 degree impact ； Q235D level is -20 degree impact. At different impact temperatures, the impact values are also different. Element content: The sulfur content of A, B, C, and D decreases in sequence. ； A and B have the same phosphorus content, C has the second highest phosphorus content, and D has the least phosphorus content. Q235 Chemical composition of each level: Q235 is divided into four grades A, B, C and D (GB700-88) Q235 grade A contains C0.14~0.22% Mn0.30~0.65 Si≤0.30 S≤0.050 P≤0.045 Q235 grade B contains C0.12~0.20% Mn0.30~0.670 Si≤0.30 S≤0.045 P≤0.045 Q235C grade contains C≤0.18% Mn0.35~0.80 Si≤0.30 S≤0.040 P≤0.040 Q235D grade contains C≤0.17% Mn0.35~0.80 Si≤0.35 S≤0.040 P≤0.035 As far as the deoxidation method is concerned, F, b, and z can be used to represent boiling steel, dead steel, and killed steel respectively. Boiling steel is steel with incomplete deoxidation and poor plasticity and toughness. Welded structures made of this material are prone to cracks in the joints when subjected to dynamic loads. It is not suitable to work at low temperatures, as hardening may occur sometimes. In contrast, killed steel is fine and uniform, with good plasticity and toughness.