牌号解释
H:冷成形用高强度扁平材，flat products of high strength for cold forming
C:冷轧，cold rolled
300:规定的小屈服强度，MPa
LA:低合金钢，low alloy steels
D:热镀代号，for hot dip coating
Z:纯锌镀层，zinc coating
成分(Wt%)
C碳元素:<=0.11
Si硅元素:<=0.5
Mn锰元素:<=1
P磷元素:<=0.03
s硫元素:<=0.025
Nb铌元素:<=0.09
Ti钛元素:<=0.15
Al铝元素:>=0.015
组合公式1:Nb+Ti+V+B