A blue bar that separates the head section of the site from the body

G2S Gray Iron

Dura-Bar G2S is a high strength highly pearlitic gray iron. It combines both superior strength and surface hardenability attributes. By an addition of molybdenum, G2S maintains excellent strength throughout the cross-section of the bar. A minimum of 40,000 psi tensile strength from the mid-radius is achieved. Using additional alloying elements, the carbon-rich material needed for effective induction or flame hardening is an additional compliment to G2S. G2S is ideal for applications where strength, hardenability, and creep resistance are required. To learn more, download the G2S Gray Iron Product Brief.

Typical Applications



Fluid Power:

Cylinder blocks, Glands, Manifolds, Pistons, Rotors, Spools, Valves


Bushings, Gears, Gibs, Housings, Pulleys, Rams, Sheaves, Side Frames, Slides, Spindles, Ways


Aluminum Molds Plates, Cams, Chain Sheaves, Core Boxes, Dies, Pattern Plates, Wheels

Oil and Gas:

Bridge Plugs, Cement Plugs, Cones, Mandrels, Retainers, Slips

Power Transmission:

Gears, Pulleys

Pump and Compressor:

Gears, Housings, Liners, Pistons, Rollers, Rotors, Seals

Steel Mill:

Continuous Caster Rolls, Foot Rolls, Table Rolls, Torch Rolls


Brake Rotors, Cylinder Liners, Gears, Lash Adjusters, Pulleys, Shock Absorber Pistons, Valve Guides, Valve Seat Inserts


The microstructure will contain Type VII, A, size 4-6 graphite as defined in ASTM A247. The matrix is fully pearlitic. The edge or rim will consist of Type D, size 6-8 graphite in a matrix consisting of 80% pearlite. Chill carbides will be less than 5% in any field at 100x and are well dispersed.

A graph detailing the microstructure of the G2S

Chemical Composition

Carbon and silicon targets are specified for each bar size in order to control the size and shape of the graphite flake. Alloying elements are used to promote enhanced tensile strength and to stabilize the pearlitic structure.

Carbon2.60 - 3.75%
Silicon1.80 - 3.00%
Manganese0.60 - 0.95%
Sulfur0.07% Max
Phosphorus0.12% Max

Mechanical Properties

Brinell hardness values for nominal as-cast diameters are shown in the table. Hardness properties listed are minimum and maximum across the bar. Hardness values for rectangles and squares are a function of the height and width ratios and will be supplied on request.

Size Range

2.500 - 6.00064 - 152



Tensile strength is determined from a test bar removed from the mid-radius of a continuous cast bar. Test bars from the mid-radius will meet the minimum 40,000 psi listed in the table below. Since mid-radius test bars meet a 40,000 psi class of iron, separately cast bars are cast for reference only.

Mechanical Properties
Tensile strength psi (min)40,000
Yield strength psi (min)n/a*
Elongation (min)n/a*

*Gray iron will not yield/elongate before fracture. The behavior of gray iron is non-ductile.

Call us today to discuss your application at 888-DURA-BAR (888.387.2227) or click to complete our quote form.