Introduction of low temperature Ni series 9Ni590A steel plate

9Ni590A pressure vessel steel is Ni series low temperature steel with thickness ≤50mm, used for -196 degrees Celsius low temperature environment. It is used to manufacture low temperature pressure vessels such as liquefied natural gas (LNG) storage tanks and liquefied natural gas (LNG) ships.

9Ni590A steel plate executive standard: GB 24510-2017.

9Ni590A steel plate delivery status: quenched and tempered, twice quenched + tempered.

Melting analysis of chemical composition of 9Ni590A steel plate:

C	Si	Mn	P	S	Ni	Cr	Mo	Cu	V
≤0.1	≤0.35	0.3-0.8	≤0.015	≤0.010	8.5-10	≤0.25	≤0.1	≤0.35	≤0.05

Remarks for composition: When the steel contains Al (Als≥0.015) or other nitrogen-fixing elements, N≤0.012, otherwise N≤0.009; Cr+Mo+Cu≤0.5.

Mechanical properties of 9Ni590A steel plate:

Delivery Status	Thickness	Mechanical properties
Quenching and tempering	≤30mm	ReH(MPa)	≥590	When the yield is not obvious, use Rp0.2
		Rm(MPa)	680-820
		A(%)	≥18
		Impact Temperature	-196
		Akv(J)	≥50	Horizontal
		Remark	Delivery status: quenched + tempered or twice quenched + tempered; steel plates with thickness ≤ 15mm can be delivered in twice normalized + tempered states
	>30-50mm	ReH(MPa)	≥575	When the yield is not obvious, use Rp0.2
		Rm(MPa)	680-820
		A(%)	≥18
		Impact Temperature	-196
		Akv(J)	≥50	Horizontal
		Remark	Delivery status: quenched + tempered or twice quenched + tempered

9Ni590A steel plate is widely used in key parts of cryogenic pressure vessels such as LNG storage tanks and cryogenic transport tankers.