ABS Grade A Plate – Properties, Chemistry & Equivalents

ABS Grade A (also written AB/A, ABS/A, Grade A steel plate) is an ordinary-strength hull structural steel defined in ABS Rules Part 2 and ASTM A131, an IACS unified grade, with minimum yield strength 235 MPa and tensile strength 400-520 MPa.

 

Gangsteel is specialized in supplying ABS general strength steel plate in ABS Grade A. For more information of Grade A steel plate, please check them in following:

 

 

 

ABS GRADE A general Strength Chemical Composition

ABS GRADE A

ABS Grade A chemical composition, % – heat (ladle) analysis and product (check) analysis

Element	Heat analysis (max/min)	Product analysis
C	≤ 0.21	≤ 0.25
Mn	≥ 2.5×C	— (min-only limit; A6 Table A band is keyed to an upper limit, so no product value given)
Si	≤ 0.50	≤ 0.56
P	≤ 0.035	≤ 0.045
S	≤ 0.035	≤ 0.045
C + Mn/6	≤ 0.40	— (calculated from heat analysis)

Ni, Cr, Mo and Cu are to be determined and reported (no ABS limit, so no product value). Product analysis = heat limit ± ASTM A6/A6M Table A permitted variation (band chosen by the specified maximum/upper limit); applies only when product (check) analysis is required; for a range, results may not vary both above and below it. Per ABS Rules for Materials and Welding Part 2 (2022); product analysis tolerances per ABS 2-1-2/5.3 (“chemical tolerances of ASTM A6”) and ASTM A6/A6M 7.2, Table A (also invoked by ASTM A131). Heat limits: ABS 2-1-2/15.9 Table 1 (t ≤ 150 mm).

Crack Sensitivity:  Pcm = (C+Si/30+Mn/20+Cu/20+Ni/60+Cr/20+Mo/15+V/10+5B)%
Carbon Equivalent:  Ceq = 【C+Mn/6+(Cr+Mo+V)/5+(Ni+Cu)/15】%

 

 

 

ABS GRADE A generalstrength property

ABS GRADE A

ABS Grade A mechanical properties by thickness

Thickness (mm)	Yield min (MPa)	Tensile (MPa)	Elongation A5 min (%)	Charpy test temp (°C)	Impact avg min, longitudinal (J)	Impact avg min, transverse (J)
t≤50	235	400-520	22	+20	-	-
50<t≤70	235	400-520	22	+20	34	24
70<t≤100	235	400-520	22	+20	41	27

Source: ABS Rules Pt 2, 2-1-2 Tables 2 & 4. Either direction acceptable. Grade A: no impact test required up to 50 mm; above 50 mm not required when fine-grain practice and normalized.

Boiler steel plates| Alloy steel plates| High strength plate| Carbon steel plate

 

 

 

 

 

Equivalent steel grade of ABS GRADE A
DNV	GL	LR	BV	CCS	NK	KR	RINA
NV A	GL-A	LR/A	BV/A	CCS/A	K A	R A	RI/A

 

 

 

 

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

 

 Related steel grades: AB/B, AB/D, AB/E, AB/AH32

 

ABS Steel Plate Grade Supplier
General Strength	AB/A	AB/B	AB/D	AB/E
High Strength	AB/AH32	AB/DH32	AB/EH32	AB/FH32
	AB/AH36	AB/DH36	AB/EH36	AB/FH36
	AB/AH40	AB/DH40	AB/EH40	AB/FH40
Extra Strength	AB/AQ43	AB/DQ43	AB/EQ43	AB/FQ43
	AB/AQ47	AB/DQ47	AB/EQ47	AB/FQ47
	AB/AQ51	AB/DQ51	AB/EQ51	AB/FQ51
	AB/AQ56	AB/DQ56	AB/EQ56	AB/FQ56
	AB/AQ63	AB/DQ63	AB/EQ63	AB/FQ63
	AB/AQ70	AB/DQ70	AB/EQ70	AB/FQ70

 

 

Thickness and impact test

Grade A plates up to 50 mm normally need no Charpy test; thicker plates are tested per the rules. ABS rules cover hull plates up to 100 mm.

ABS Grade A equivalents

ABS	ASTM A131	DNV	LR	BV	CCS
Grade A	Grade A	Grade A	Grade A	Grade A	Grade A

All follow IACS UR W11; the plate must still carry the certificate of the society required by the project.

FAQ

What is ABS Grade A steel?

ABS Grade A is an ordinary-strength hull structural steel defined in ABS Rules Part 2 and ASTM A131, with minimum yield strength 235 MPa and tensile strength 400-520 MPa.

What is the impact test temperature for ABS Grade A?

Grade A plates up to 50 mm normally need no Charpy test; thicker plates are tested per the rules.

What is the chemical composition of ABS Grade A?

Per the page table: C ≤0.21% (Grade E ≤0.18%), P and S ≤0.035% each; Mn and Si limits differ by grade — see the table above.

What are the equivalents of ABS Grade A?

ABS Grade A corresponds to ASTM A131 Grade A and to Grade A of other IACS societies such as DNV, LR, BV and CCS, since all follow IACS UR W11; the plate must still carry the certificate of the society required by the project.

What thickness is ABS Grade A available in?

ABS rules cover hull plates up to 100 mm; the property table above lists values for t≤50, 50<t≤70 and 70<t≤100 mm. Please confirm actual sizes with Gangsteel sales.

ASTM equivalent: ASTM A131 Grade A steel plate

LR equivalent: LR Grade A steel plate