Chemical Composition

Element	Composition, % Classes 60 and 70
Carbon, max	0.35
Manganese, max	1.10A
Phosphorus, max	0.05
Silicon	0.10-0.35
Sulfur, max	0.05

Note:

A. Manganese may be increased to 1.65 % max provided the carbon is reduced 0.01 % for each 0.06 % increase in manganese over the limit shown in the table.

Mechanical Properties

	Class 60	Class 70
Tensile strength, min, ksi [MPa]	60 [415]	70 [485]
Yield strength,A min, ksi [MPa]	30 [205]	36 [250]
Elongation in 2 in. [50 mm], min, %	22	18
Reduction of area, min, %	35	24

Note:

A. Determined by either the 0.2 % offset method or the 0.5 % extension-under-load method.

Referenced Documents

ASTM A266/A266M	Specification for Carbon Steel Forgings for Pressure Vessel Components.
ASTM A788/A788M	Specification for Steel Forgings, General Requirements.
ASTM A961/A961M	Specification for Common Requirements for Steel Flanges, Forged Fittings, Valves, and Parts for Piping Applications.