Difference between DNV E460 and DNV D460 steel plate - Knowledge

DNV D460 and E460 are both high-strength shipbuilding steels with 460 MPa yield strength, but the key difference lies in their toughness requirements, especially at low temperatures: DNV E460 is a superior grade, requiring Quenched & Tempered (Q&T) heat treatment and much higher impact toughness, often tested at -40°C, making it ideal for colder ocean conditions, while D460 offers lower-end toughness or normalized conditions, suited for less severe environments, though both aim for structural strength.

Chemical Composition

NV D460 extra high Strength Chemical Composition
Grade	The Element Max (%)
Grade	C	Si	Mn	P	S	Al	N
NV D460	0.20	0.10-0.55	1.7	0.030	0.030	0.015-0.08	0.020
	Nb	V	Ti	Cu	B	Ni	Mo
	0.02-0.05	0.04-0.10	0.02		0.005

NV E460 extra high Strength Chemical Composition
Grade	The Element Max (%)
Grade	C	Si	Mn	P	S	Al	N
NV E460	0.20	0.10-0.55	1.7	0.030	0.030	0.015-0.08	0.020
	Nb	V	Ti	Cu	B	Ni	Mo
	0.02-0.05	0.04-0.10	0.02		0.005

Mechanical Property

NV D460 extra high general strength property
Grade		Mechanical Property			Charpy V Impact Test
Grade	Thickness	Yield	Tensile	Elongation	Degree	Energy 1	Energy 2
NV D460	mm	Min Mpa	Mpa	Min %	-20	J	J
	t≤50	460	570-720	17%		31	46
	50＜t≤70	460	570-720	17%		31	46
	70＜t≤150	460	570-720	17%		31	46
Note: Energy 1 is transverse impact test, Energy 2 is longitudinal

NV E460 extra high general strength property
Grade		Mechanical Property			Charpy V Impact Test
Grade	Thickness	Yield	Tensile	Elongation	Degree	Energy 1	Energy 2
NV E460	mm	Min Mpa	Mpa	Min %	-40	J	J
	t≤50	460	570-720	17%		31	46
	50＜t≤70	460	570-720	17%		31	46
	70＜t≤150	460	570-720	17%		31	46
Note: Energy 1 is transverse impact test, Energy 2 is longitudinal

DNV D460 (Normal Grade):

Strength: 460 MPa minimum yield strength.

Toughness: Standard toughness, often achieved through normal rolling or normalizing, suitable for less extreme cold.

DNV E460 (Enhanced Grade):

Strength: Also 460 MPa minimum yield strength.

Toughness: Significantly higher, requiring Quenched & Tempered (Q&T) heat treatment and mandatory low-temperature impact tests (e.g., at -40°C) for superior performance in cold climates.

Z-Test: Often includes Z-direction properties (Z15, Z25, Z35) for better through-thickness strength, crucial for thick plates.

In Simple Terms: Think of E460 as a more robust, cold-weather version of D460, designed for ships and structures exposed to harsher, colder marine environments, whereas D460 is for general shipbuilding where extreme cold isn't the primary concern.