The main material of common medical and industrial gas cylinders is 37Mn steel of Mn series. Normalizing treatment is mainly adopted for cylinder steel. However

the mechanical properties of normalized 37Mn cylinder steel are unstable

and it yield strength and impact energy cannot meet setting in standards. In this paper

by adding Cr and N micro elements

the chemical composition of microalloying 37Mn steel is /% ：0.34 ~0.38 C

0.20 ~0.27 Si

1.60 〜1.70 Mn

0.10 ~0.20 Cr

0.004 0 ~0.0090N

of normalized rolled;219mm x6mm steel tube

the yield strength≥530 MPa

tensile ≥750 MPa and impact energy 13.2J

fully meet the needs of customer.