ASTM A325 Type 3 Specification

ASTM A325 Type 3 Specification for heat treated weathering steel structural bolts, steel, heat treated with 120 ksi Minimum Tensile Strength

ASTM A325 Type 3 is a standard material specification for high strength weathering steel fasteners, for use in high tensile structural bolting and other general purpose applications. Type 3 is a quenched and tempered weathering steel bolting material with minimum tensile requirement of 105 ksi, yield 81 ksi and maximum hardness requirement of 34 HRC. This specification is used for manufacturing heavy profile bolts, screws, stud bolts, threaded rods, anchor bolts and other externally threaded fasteners. A325 specification covers requirements for chemical composition, mechanical properties, hardness, heat treatment, recommended nuts-washers for Type 3 fasteners.

Chemical Composition

Element Type 3, %
A B C D E F
Carbon 0.31 - 0.42 0.36 - 0.50 0.14 - 0.26 0.14 - 0.26 0.18 - 0.27 0.19 - 0.26
Manganese 0.86 - 1.24 0.67 - 0.93 0.76 - 1.39 0.36 - 1.24 0.56 - 1.04 0.86 - 1.24
Phosphorus 0.040 max 0.040 max 0.040 max 0.040 max 0.040 max 0.040 max
Sulfur 0.045 max 0.045 max 0.045 max 0.045 max 0.045 max 0.045 max
Silicon 0.13 - 0.37 0.25 - 0.55 0.13 - 0.37 0.20 - 0.55 0.13 - 0.37 0.13 - 0.37
Copper 0.22 - 0.48 0.17 - 0.43 0.17 - 0.53 0.27 - 0.53 0.27 - 0.63 0.17 - 0.43
Nickel 0.22 - 0.48 0.47 - 0.83 0.22 - 0.53 0.47 - 0.83 0.27 - 0.63 0.17 - 0.43
Chromium 0.42 - 0.68 0.47 - 0.83 0.27 - 0.53 0.45 - 1.05 0.55 - 0.95 0.42 - 0.68
Vanadium ... ... 0.010 min ... ... ...
Molybdenum ... 0.07 max ... 0.11 max ... ...
Titanium ... ... ... 0.06 max ... ...

Mechanical Properties

Nominal
Diameter,
Inch		 Tensile
Strength, min,
ksi		 Yield
Strength, min,
ksi		 Elongation
in 4D, min,
%		 Reduction
in Area, min,
%		 Bolt Length,
Inch		 Brinell Rockwell C
Min Max Min Max
1/2" to 1", Inclusive 120 92 14 35 Less than 2D
2D and over		 253
...		 319
319		 25
...		 34
34
Over 1 to 1-1/2" 105 81 14 35 Less than 3D
3D and over		 223
...		 286
286		 19
...		 30
30

where D is nominal diameter or thread size.

Recommended Nuts & Washers

Nuts (Plain Finish) Washers (Plain Finish)
ASTM A563 Grade C3, DH3 ASTM F436 Type 1