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ASTM B121 Specification

Forgings, Fasteners, Boltings, Stud Bolts, Screws, Nuts

Scope

ASTM B121 specification establishes the requirements for copper-zinc-lead alloys (leaded brass) plate, sheet, strip, and rolled bar. The following alloys are covered:

Copper Alloy UNS No.2 Previously Used Designation Nominal Composition, %
Cu Zn Pb Fe
C33500 2 65.0 34.5 0.5 ...
C34000 3 65.0 34.0 1.0 ...
C34200 5 65.0 33.0 2.0 ...
C35000 ... 61.5 37.4 1.1 ...
C35300 4 61.2 37.0 1.8 ...
C35600 6 61.2 36.3 2.5 ...

The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.

Related Specifications of ASTM B121

ASTM B121 Chemical Composition

Cu Alloy UNS No. Composition
Cu Pb Fe Zn
C33500 62.0-65.0 0.25-0.7 0.10 max remainder
C34000 62.0-65.0 0.8-1.5 0.10 max remainder
C34200 62.0-65.0 1.5-2.5 0.10 max remainder
C35000 60.0-63.0 0.8-2.0 0.10 max remainder
C35300 60.0-63.0 1.5-2.5 0.10 max remainder
C35600 60.0-63.0 2.0-3.0 0.10 max remainder

ASTM B121 Mechanical Requirements

Tensile Strength Requirements and Approximate Rockwell Hardness Values for Rolled Tempers

Temper DesignationA Tensile Strength ksiC [MPa]D Approximate Rockwell HardnessB
Standard Former Min Max B Scale Superficial 30-T
Copper Alloy UNS Nos. C33500, C34000, C34200, C35000, C35300, and C35 600
H01 quarter-hard 49 [340] 59 [405] 40-65 43-60
H02 half-hard 55 [380] 65 [450] 57-74 54-66
H04 hard 68 [470] 78 [540] 76-84 68-73
H06 extra-hard 79 [545] 89 [615] 83-89 73-76
H08 springE 86 [595] 95 [655] 87-92 75-78
H10 extra-springE 90 [620] 99 [685] 88-93 76-79
  • A Standard designations defined in Classification B601.
    B Rockwell Hardness values apply as follows: The B scale hardness values apply to metal 0.020 in. (0.508 mm) and over in thickness, and The 30-T scale hardness values apply to metal 0.012 in. (0.305 mm) and over in thickness.  
    • ksi = 1000 psi.
    • See Appendix.
    • Spring and extra spring temper are generally furnished only in alloy No. 353.

Grain Size Requirements for Annealed Material

Copper Alloy UNS No. Standard Temper Designation Grain Size, mm
Nominal Min Max
C33500, C34000, C34200, C35000, C35300, C35600 OS070 0.070 0.050 0.100
OS050 0.050 0.035 0.070
OS035 0.035 0.025 0.050
OS025 0.025 0.015 0.035

Approximate Rockwell Hardness of Annealed Material

Nominal Grain
Size, mm		 Standard Temper
Designation		 Approximate Rockwell
HardnessA
F Scale Superficial 30-T
C33500, C34000, C34200, C35000, C35300, and C35600
0.070 OS070 54-67 12-27
0.050 OS050 61-73 20-35
0.035 OS035 65-76 25-38
0.025 OS025 67-69 27-42
 

ASTM B121 Certifications

  • EN 10204 3.1
  • EN 10204 3.2
  • PED 2014/68/EC
  • MERKBLATT AD 2000 W2/W7/W10
  • API 20 E BSL 1/ BSL 2
  • NACE MR 0175
  • NACE MR 0103