Introduction to low alloy steel Q345D-Z15

Q345D-Z15 is a low alloy Z-direction performance steel.
The grade of Q345D-Z15 steel consists of three parts: the yield strength, the yield strength value, and the quality grade symbol, such as Q345D. Among them: The first letter Q represents the yield strength of steel; 345- yield strength value, in MPa; D - The quality level is D (divided into A, B, C, D, E).

When the purchaser requires the steel plate to have thickness direction performance, a symbol representing the thickness direction (Z-direction) performance level should be added after the specified grade, such as Q345D-Z15, Q345-Z25, Q345D-Z35.

Mechanical properties of low alloy steel Q345D-Z15:
Yield strength:
Thickness≤ 16mm: ≥ 345;
16-40mm: ≥335;
40-63mm: ≥325;
63-80mm: ≥315;
80-100mm: ≥305;
100-150mm: ≥285;
150-200mm: ≥275;
200-250: ≥275;
250-400: ≥265.
Tensile strength: 450-630.
Elongation: ≥ 21.
Impact test: -20 ℃: ≥ 34.

Chemical composition of low alloy steel Q345D-Z15:
C: ≤0.18; Si: ≤0.50; Mn: ≤1.70; P: ≤0.030; S: ≤0.010; Nb: ≤0.07; Als: ≥0.015
V: ≤0.15; Ti: ≤0.20; Cr: ≤0.30; Ni: ≤0.50; Cu: ≤0.30; N: ≤0.012; Mo: ≤0.10