钢的牌号由代表屈服强度的汉语拼音字母,屈服强度数值,质量等级符号三个部分组成,例如: Q390C。其中: Q—钢的屈服强度的“屈”字汉语拼音首位字母; 390—屈服强度数值,单位MPa;
D—质量等级为等级(等级分为B,C,D,E)。 当需方需要钢板具有厚度方向性能时,则在上述规定的牌号后加上代表厚度方向(Z向)性能级别的符号。 Q390,是一种低合金高强度结构钢。
【化学成分】(质量分数)(%)
等级 | C | Mn | Si | P | S | V | Nb | Ti | Al | Cr | Ni |
A | ≤0.20 | 1.00~1.60 | ≤0.55 | ≤0.045 | ≤0.045 | 0.02~0.20 | 0.015~0.060 | 0.02~0.20 | - | ≤0.30 | ≤0.70 |
B | ≤0.20 | 1.00~1.60 | ≤0.55 | ≤0.040 | ≤0.040 | 0.02~0.20 | 0.015~0.060 | 0.02~0.20 | - | ≤0.30 | ≤0.70 |
C | ≤0.20 | 1.00~1.60 | ≤0.55 | ≤0.035 | ≤0.035 | 0.02~0.20 | 0.015~0.060 | 0.02~0.20 | ≥0.015 | ≤0.30 | ≤0.70 |
D | ≤0.20 | 1.00~1.60 | ≤0.55 | ≤0.030 | ≤0.030 | 0.02~0.20 | 0.015~0.060 | 0.02~0.20 | ≥0.015 | ≤0.30 | ≤0.70 |
E | ≤0.20 | 1.00~1.60 | ≤0.55 | ≤0.025 | ≤0.025 | 0.02~0.20 | 0.015~0.060 | 0.02~0.20 | ≥0.015 | ≤0.30 | ≤0.70 |