ASTM A131 FH40 Steel Plate | FH40 Shipbuilding Steel Plate

ASTM A131 FH40 steel plate, also written as A131/A131M Grade FH40, ASTM A131 FH40 steel plate, ASTM A131 FH 40, A131 Gr FH40 or simply FH40 ship steel plate, is a higher-strength hull structural steel of the A131 steel plate specification with a specified minimum yield point of 390 MPa [57 ksi] and guaranteed Charpy V-notch toughness at -60°C [-76°F]. Gangsteel, a steel plate exporter, supplies A131 FH40 plates cut to size for shipbuilding, offshore structures and other marine applications.

In the grade name, "F" is the toughness class (Charpy V-notch test at -60°C), "H" means higher strength and "40" refers to the strength level, with a minimum yield point of 390 MPa [57 ksi]. Data source: Per ASTM A131/A131M-04 (Tables 2, 4, 5, 6 and 7). The current edition is A131/A131M-19; verify against it before ordering.

ASTM A131 FH40 steel plate Chemical Composition (Heat Analysis)

 

Element	C	Mn	Si	P	S	Al (acid sol.)
FH40, %	0.16 max	0.90-1.60	0.10-0.50	0.025 max	0.025 max	0.015 min
Element	Nb	V	Ti	Cu	Cr	Ni / Mo
FH40, %	0.02-0.05	0.05-0.10	0.02 max	0.35 max	0.20 max	0.40 max / 0.08 max
Element	N	-	-	-	-	-
FH40, %	0.009 max (0.012 if Al present)	-	-	-	-	-

Per ASTM A131/A131M-04, Table 4. The steel is killed and made to fine grain practice; Al, Nb and V grain-refining elements may be used singly or in combination, and when used in combination the minimum contents of 7.2.2 and 7.2.3 apply instead. Where soluble aluminum is not less than 0.015%, the minimum silicon content does not apply. Cu, Cr, Ni and Mo may be reported as ≤0.02% when not exceeding 0.02%. Carbon equivalent: Ceq = C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15 (%), for TMCP plate limited to 0.40% max per Table 5.

Product Analysis (Check Analysis)

Per ASTM A131/A131M-04 (6.1.1 and Supplementary Requirement S85), when product analysis is specified, the finished plate shall conform to the Table 4 limits below, subject to the product analysis tolerances in ASTM A6/A6M.

Element	Limit applied to product analysis	Tolerance
C	0.16 max	per ASTM A6/A6M
Mn	0.90-1.60	per ASTM A6/A6M
Si	0.10-0.50	per ASTM A6/A6M
P / S	0.025 max	per ASTM A6/A6M
Al (acid sol.)	0.015 min	per ASTM A6/A6M
Nb / V	0.02-0.05 / 0.05-0.10	per ASTM A6/A6M
Ti	0.02 max	per ASTM A6/A6M
Cu / Cr / Ni / Mo	0.35 / 0.20 / 0.40 / 0.08 max	per ASTM A6/A6M
N	0.009 max (0.012 if Al present)	per ASTM A6/A6M

A131 FH40 Mechanical Properties

 

Grade	Yield point, min	Tensile strength	Elongation in 200 mm, min	Elongation in 50 mm, min
ASTM A131 FH40 steel plate	390 MPa [57 ksi]	510-650 MPa [74-94 ksi]	19%	22%

Per ASTM A131/A131M-04, Table 6. For thickness under 8 mm a deduction from the 200 mm elongation applies, and over 90 mm a deduction from the 50 mm elongation applies, per ASTM A6/A6M.

Charpy V-Notch Impact Requirements (-60°C)

 

Thickness	Test temperature	Longitudinal, avg min	Transverse, avg min
t ≤ 50 mm	-60°C [-76°F]	41 J [30 ft-lbf]	27 J [20 ft-lbf]
50 < t ≤ 100 mm	-60°C [-76°F]	not specified in Table 7	not specified in Table 7

Per ASTM A131/A131M-04, Table 7; average of three full-size specimens, not more than one value below the average and none below 70% of it. Either orientation is acceptable unless specified (S86). Per 8.2.2, FH40 plate is impact tested with one set of three specimens from each plate-as-rolled.

Thickness Range and Delivery Condition

ASTM A131/A131M covers plates up to 100 mm [4 in.] thick in Tables 1, 2 and 7. FH40 plates in all thicknesses shall be normalized, thermo-mechanically controlled processed or quenched and tempered (5.5); quenched and tempered plate gets one tension test per plate (8.1.4). Plates are marked N, CR, TM or QT to show the condition of supply (Section 12). Optional requirements by agreement include product analysis (S85), impact specimen orientation (S86), additional tension tests (S88), ultrasonic testing and third-party inspection.

Boiler steel plates | Alloy steel plates | Low alloy high strength steel plate | Carbon steel plate

Equivalent Steel Grade of ASTM A131 FH40 steel plate

 

DNV steel plate	GL steel plate	LR steel plate	BV steel plate	CCS steel plate	NK steel plate	KR steel plate	RINA steel plate
NV F40	GL-F40	LR/FH40	BV/FH40	CCS/F40	K F40	R F40	RI/F40

If you need more stock steel plates in shipbuilding steel plate, please click stock steel plates.

Related grades: A131 AH40 | A131 DH40 | A131 EH40

FAQ about ASTM A131 FH40 Steel Plate

What is ASTM A131 FH40 steel?

It is a higher-strength hull structural steel in ASTM A131/A131M with 390 MPa [57 ksi] minimum yield point and Charpy impact toughness at -60°C, used for ship hulls and marine structures.

What is the yield strength of A131 FH40?

Minimum 390 MPa [57 ksi], with tensile strength 510-650 MPa [74-94 ksi] (Table 6).

What is the impact test temperature for A131 FH40?

-60°C [-76°F]. Minimum average energy for t ≤ 50 mm is 41 J [30 ft-lbf] longitudinal and 27 J [20 ft-lbf] transverse.

Is A131 FH40 the same as ABS FH40?

The requirements are essentially harmonized; the ABS grade additionally carries ABS class certification and survey. Plates can be dual-certified.

What does FH40 stand for?

F = toughness class (Charpy test at -60°C), H = higher strength, 40 = strength level with 390 MPa [57 ksi] minimum yield point.

What is the carbon equivalent limit for TMCP FH40?

Per Table 5, 0.40% max, using Ceq = C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15.

What delivery condition is required for A131 FH40?

Normalized, TMCP or quenched and tempered in all thicknesses.

Is A131 FH40 weldable?

Yes. Its controlled carbon and carbon equivalent give good weldability with standard shipyard procedures; preheat may be needed for thick or highly restrained joints.

What is the maximum thickness of A131 FH40 plate?

ASTM A131/A131M-04 covers plates up to 100 mm [4 in.]; Table 7 gives impact values only up to 50 mm for this grade, so heavier plate needs agreement.

Other ASTM A131 Grades

ASTM A131 Grade A steel plate | ASTM A131 Grade B steel plate | ASTM A131 Grade D steel plate | ASTM A131 Grade E steel plate | ASTM A131 AH32 steel plate | ASTM A131 AH36 steel plate | ASTM A131 AH40 steel plate | ASTM A131 DH32 steel plate | ASTM A131 DH36 steel plate | ASTM A131 DH40 steel plate | ASTM A131 EH32 steel plate | ASTM A131 EH36 steel plate | ASTM A131 EH40 steel plate | ASTM A131 FH32 steel plate | ASTM A131 FH36 steel plate

Equivalent Class Society Grades

ASTM A131 FH40 corresponds to the same grade under the IACS member classification societies: CCS FH40 steel plate, ABS FH40 steel plate, LR FH40 steel plate.