ABS Steels
Encyclopedia
ABS Steels are types of structural steel
Structural steel
Structural steel is steel construction material, a profile, formed with a specific shape or cross section and certain standards of chemical composition and mechanical properties...

 which are standardized by the American Bureau of Shipping
American Bureau of Shipping
The American Bureau of Shipping is a classification society, with a mission to promote the security of life, property and the natural environment, primarily through the development and verification of standards for the design, construction and operational maintenance of marine-related facilities...

 for use in shipbuilding
Shipbuilding
Shipbuilding is the construction of ships and floating vessels. It normally takes place in a specialized facility known as a shipyard. Shipbuilders, also called shipwrights, follow a specialized occupation that traces its roots to before recorded history.Shipbuilding and ship repairs, both...

.
ABS steels come many grades in ordinary-strength and two levels of higher-strength specifications.

All of these steels have been engineered to be optimal long-lived shipbuilding steels. ABS does permit the use of other steels in shipbuilding, but discourages it, and requires more detailed engineering analysis.

Basic properties

All ABS steels are standard carbon steels. As with other grades of steel, they have a specific gravity
Specific gravity
Specific gravity is the ratio of the density of a substance to the density of a reference substance. Apparent specific gravity is the ratio of the weight of a volume of the substance to the weight of an equal volume of the reference substance. The reference substance is nearly always water for...

 of 7.8.

Ordinary-Strength

Ordinary-strength ABS shipbuilding steel comes in a number of grades, A, B, D, E, DS, and CS. On certified steels, the plates are marked with the grade and a preceding "AB/", i.e. AB/A etc.
Yield point for all ordinary-strength ABS steels is specified as 34,000 psi (235 MPa), except for ABS A in thicknesses of greater than 1 inch (25 mm) which has yield strength of 32,000 psi (225 MPa), and cold flange rolled sections, which have yield strength of 30,000 psi (205 MPa).

Ultimate tensile strength
Tensile strength
Ultimate tensile strength , often shortened to tensile strength or ultimate strength, is the maximum stress that a material can withstand while being stretched or pulled before necking, which is when the specimen's cross-section starts to significantly contract...

 of ordinary strength alloys is 58,000 - 71,000 psi (400-490 MPa), except for ABS A shapes and bars with 58,000 - 80,000 psi (400-550 MPa), and cold flanged sections with 55,000 - 65,000 psi (380-450 MPa).

The various grades have slightly differing alloy
Alloy
An alloy is a mixture or metallic solid solution composed of two or more elements. Complete solid solution alloys give single solid phase microstructure, while partial solutions give two or more phases that may or may not be homogeneous in distribution, depending on thermal history...

 chemical ingredients, and differing fracture toughness
Fracture toughness
In materials science, fracture toughness is a property which describes the ability of a material containing a crack to resist fracture, and is one of the most important properties of any material for virtually all design applications. The fracture toughness of a material is determined from the...

.

Higher-Strength

Higher-strength ABS shipbuilding steel comes in six grades of two strengths, AH32, DH32, EH32, AH36, DH36, and EH36.

The 32 grades have yield strength of 45,500 psi (315 MPa), and ultimate tensile strength of 64,000 - 85,000 psi (440-590 MPa).

The 36 grades have yield strength of 51,000 psi (355 MPa), and ultimate tensile strength of 71,000 - 90,000 psi (490-620 MPa).

Per Steel Vessel Rules Part 2 Chapter 1 Section 3 Table 2 (pg 36).
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