Matched by chemical composition and mechanical properties, not a formal equivalence claim. Always verify against the applicable standard before substitution.
Chemical Composition (%)
C
Mn
P
S
Si
Cr
Mo
1.25-1.55
0.30-1.10
<=0.030
<=0.030
0.55-1.50
<=0.30
0.20-0.30
Mechanical Properties
Hardness
<=229 HB
Condition
Annealed (maximum Brinell hardness)
More data from ASTM A681:2008
From the standard
Maximum hardness in delivery condition2 conditions
Condition
Maximum hardness (HB)
Annealed
229
Cold drawn
241
Maximum Brinell hardness (BHN).
Source: A681:2008, Table 2
Heat treatment and response to hardeninghardening test conditions
Austenitizing, salt bath
1450 deg F (788 deg C)
Austenitizing, controlled atmosphere furnace
1475 deg F (802 deg C)
Austenitizing time
5 to 15 min
Quench medium
Oil
Tempering temperature
400 deg F (204 deg C)
Minimum hardness after treatment
59 HRC
Austenitizing temperatures are stipulated for the response to hardening test only.
Source: A681:2008, Table 3
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