ASTM A871/A871M

This specification covers high-strength low-alloy steel plate intended for use in tubular structures and poles or in other suitable applications. Two grades, 60 and 65, may be provided as-rolled, normalized or quenched and tempered as required to meet the specified mechanical requirements.The atmospheric corrosion resistance of this steel in most environments is substantially better than that of carbon structural steels with or without copper addition (see Note 1). When properly exposed to the atmosphere, this steel can be used bare (unpainted) for many applications.

ASTM A871/A871M Chemical Composition

Element	Composition, %
Element	Type I	Type II	Type III	Type IV
Carbon	0.19 max	0.20 max	0.15 max	0.17 max
Manganese	0.80–1.35	0.75–1.35	0.80–1.35	0.50–1.20
Phosphorus	0.04 max	0.04 max	0.04 max	0.04 max
Sulfur	0.05 max	0.05 max	0.05 max	0.05 max
Silicon	0.30–0.65	0.15–0.50	0.15–0.40	0.25–0.50
Nickel	0.40 max	0.50 max	0.25–0.50	0.40 max
Chromium	0.40–0.70	0.40–0.70	0.30–0.50	0.40–0.70
Molybdenum	...	...	...	0.10 max
Copper	0.25–0.40	0.20–0.40	0.20–0.50	0.30–0.50
Vanadium	0.02–0.10	0.01–0.10	0.01–0.10	. . .
Columbium	. . .	. . .	. . .	0.005–0.05B

A For each reduction of 0.01 percentage point below the specified maximum for carbon, an increase of 0.06 percentage point above the specified maximum for manganese is permitted, up to a maximum of 1.50 %.
B For plates under 1⁄2 in. [13 mm] in thickness, the minimum columbium is waived.

ASTM A871/A871M Mechanical Properties

Grade	Tensile strength, min, ksi [MPa]	Yield point, min, ksi [MPa]	Minimum Elongation, %C
Grade	Tensile strength, min, ksi [MPa]	Yield point, min, ksi [MPa]	In 8 in. [200 mm]	In 2 in. [50 mm]
60	60 [415]	75 [520]	16	18
65	65 [450]	80 [550]	15	17

Note:

A For plates wider than 24 in. [600 mm], the test specimen is taken in the transverse direction. See 11.2 of Specification A 6/A 6M.

B Measured at 0.2 % offset or 0.5 % extension under load as described in Section 13 on yield strength of Test Methods A 370.

C For plates wider than 24 in. [600 mm], the elongation requirement is reduced three percentage points.