ASTM A242 / A242M

This specification covers high-strength low-alloy structural steel shapes, plates, and bars for welded, riveted, or bolted construction intended primarily for use as structural members where savings in weight [mass] or added durability are important. The atmospheric corrosion resistance of the steel in most environments is substantially better than that of carbon structural steels with or without copper addition. When properly exposed to the atmosphere, this steel can be used bare (unpainted) for many applications. This specification is limited to material up to 4 in. [100 mm], inclusive, in thickness.

Chemical Properties

Carbon,max Manganese,max Phosphorus,max Sulfur,max Copper, min
0.15 1.00 0.15 0.05 0.20

Mechanical Properties

Products & Types Tensile strength,min: ksi [MPa] Yield strength,min: ksi [MPa] Elongation in 8 in. [200 mm] min, %A Elongation in 2 in. [50 mm] min, %A,B
Plates and BarsA For thicknesses
3/4 in.[20 mm],
andunder
70 [480] 50 [345] 18B,C 21C
For thicknesses
over 3/4 to 11/2 in.
[20 to 40
mm], incl
67 [460] 46 [315] 18B,C 21C
For thicknesses
over 11/2 to 4 in.
[40 to 100
mm], incl
63 [435] 42 [290] 18B,C 21C
Structural Shapes For flange or
leg thicknesses
1.5 in. [40 mm]
and under
70 [485] 50 [345] 18C 21
For flange
thicknesses
over 1.5 in.
[40 mm] to
2 in. [50
mm], incl
67 [460] 46 [315] 18 21
For flange
thicknesses
over 2 in.
[50 mm]
63 [435] 42 [290] 18 21D

Products