Commonly Used Metal Material Grades

Commonly used metal material grade representation (II)

Examples and descriptions of steel product grades

Pig iron grades are expressed by the symbols and Arabic numerals specified in Table

1. Arabic numerals indicate the average silicon content (in parts per thousand).

For example, the silicon content of 2.75% ~ 3.25% of the casting pig iron, the grade said “Z 30”.

Silicon content of 0.85% to 1.25% of the pig iron for steelmaking, the grade is expressed as “L 10”.

2. vanadium pig iron and decarburized low phosphorus grain iron, Arabic numerals indicate the average content of vanadium and carbon (both in parts per thousand).

For example, “F 40” for pig iron containing not less than 0.40% vanadium and “TL 14” for decarburized low phosphorus granulated iron for steelmaking with a carbon content of 1.20% to 1.60%.

Carbon structural steel and low-alloy high-strength structural grades are usually divided into two categories: general-purpose steel and special steel.

1, general structural steel using the letter “Q” representing the yield point. The yield point value (unit is MPa) and quality grade, deoxidation method, and other symbols, in order to form the grade. For example carbon steel

Structural steel grades are: Q235AF, Q235BZ; low-alloy high-strength structural steel grades are: Q 345C, Q 345C, Q 345BZ.

for: Q 345C, Q345D. In the composition of carbon structural steel grades, the symbols “Z” and “TZ” can be omitted, e.g., quality grade C and D respectively.

For example, Q235 steel of quality grades C and D, respectively, should be Q235CZ and Q235DTZ but can be omitted as Q 235C and Q 235D.

Q235D. Low-alloy, high-strength structural steels are available as sedimentation steels and special sedimentation steels, but the symbols indicating the method of deoxidation are not added to the end of the grade.

2, special structural steel is generally used on behalf of the steel yield point symbol “Q”, yield point value and on behalf of the product use of the symbol, such as pressure vessel steel grade is expressed as “Q345R”; weathering steel grade is expressed as Q340NH.

3, according to the need, the general low-alloy high-strength structural steel grades can also be used two Arabic numerals ( in parts per million average carbon content ) and the standard element symbols; special low-alloy high-strength structural steel grades, in addition to the general composition, should be added to the symbols specified in Table 1 on behalf of the product use.

Commonly Used Metal Material Grades

High-quality carbon structural steel and high-quality carbon spring steel-grades

High-quality carbon structural steel using two Arabic numerals (in parts per million to indicate the average carbon content) or Arabic numerals and elemental symbols, the combination of the required symbols into a grade.

1, boiling steel and semi-sedentary steel, the symbols “F” and “b” are added to the end of the grade. For example the average carbon content of 0.08% of the boiling steel, the grade is expressed as “08F”; the average carbon content of 0.10% of the semi-sedated steel, the grade is expressed as “10b”.

2, quiescent steel (S, P ≤ 0.035% respectively) is generally not marked symbols. For example the average carbon content of 0.45% of the sedimentation steel, the grade is expressed as “45”.

3, higher manganese content of high-quality carbon structural steel, in the average carbon content of the Arabic numerals followed by the manganese element symbol. For example, the average carbon content of 0.50%, manganese content of 0.70% ~ 1.00% of the steel, the grade is expressed as “50Mn”.

4, high-quality carbon structural steel (S, P ≤ 0.030% respectively), in the grade followed by the symbol “A”. Example

For example the average carbon content of 0.45% of high-quality carbon structural steel, its grade is shown as “45A”.

Extra high-quality carbon structural steel (S ≤ 0.020%, P ≤ 0.025%), followed by the symbol “E”

For example the average carbon content of 0.45% of high-quality carbon structural steel, the grade is expressed as “45E”.

High-quality carbon spring steel grades are expressed in the same way as high-quality carbon structural steel grades (65, 70, 85, 65Mn steel in GB/T1222 and GB/T699 standards, respectively).