Post Stock Login Register

UNI 7845 42CrMo4 vs GOST 4543 12HN3A

Minimal Match — 35% match based on chemical composition and mechanical property overlap.

UNI 7845 42CrMo4 (UNI 7845:1978) and GOST 4543 12HN3A (GOST 4543-2016) are both steel grades. Both fall under the Alloy Steel category. UNI 7845 42CrMo4 is typically used for shafts,gears,axles,studs,forgings,machine components,automotive parts,hydraulic parts, while GOST 4543 12HN3A is commonly used for used for gears, pinions, crankshafts, aircraft parts, and transmission components.. UNI 7845 42CrMo4 is defined under Ente Nazionale Italiano di Unificazione (UNI) (Italy).

As per chemical composition, UNI 7845 42CrMo4 vs GOST 4543 12HN3A is a 54.9% match. As per mechanical properties, the match is 15%. Combined, this makes them a minimal match overall at 35%.

Frequently Compared With UNI 7845 42CrMo4:
NF A35-565 100C6 UNI 11234 100Cr6 IS 1570 (Part 4) 103Cr6 IS 4367 07Cr4Mo6 IS 4367 10Cr9Mo10 IS 1570 (Part 4) 103Cr4 IS 1570 (Part 4) 105Cr5 IS 1570 (Part 7) 10Cr36Mo10H IS 1570 (Part 4) 10Mo6 IS 1570 (Part 4) 07Cr4Mo6 IS 1570 (Part 4) 10Cr20Mo6 EN 10028-2 10CrMo9-10
Match Breakdown
CHEMISTRY MATCH
54.9%
MECHANICAL MATCH
15%
OVERALL
35%
Specifications
Property UNI 7845 42CrMo4 GOST 4543 12HN3A
Standard UNI 7845:1978 GOST 4543-2016
Category Alloy Steel Alloy Steel
C (%) 0.38-0.45 0.09-0.16
Si (%) <=0.40 0.17-0.37
Mn (%) 0.60-0.90 0.3-0.6
P (%) <=0.025 Not specified
S (%) <=0.035 Not specified
Cr (%) 0.90-1.20 0.6-0.9
Mo (%) 0.15-0.30 Not specified
Ni (%) Not specified 2.75-3.15
Matched by chemical composition and mechanical properties, not a formal equivalence claim. Always verify against the applicable standard before substitution.
Mechanical Properties
Property UNI 7845 42CrMo4 GOST 4543 12HN3A
Tensile Strength 900-1100 MPa 850-1050 MPa
Yield Strength 700-900 MPa 685 MPa min
Elongation 11-16 % 11% min
Hardness 248-320 HB 58-62 HRC (case)
Typical Applications
UNI 7845 42CrMo4
shafts,gears,axles,studs,forgings,machine components,automotive parts,hydraulic parts
GOST 4543 12HN3A
Used for gears, pinions, crankshafts, aircraft parts, and transmission components.
Key Differences
Can UNI 7845 42CrMo4 Be Substituted With GOST 4543 12HN3A?
UNI 7845 42CrMo4 and GOST 4543 12HN3A share some compositional similarity but differ enough that substitution should not be assumed. Review the differences above carefully, and consult the applicable standard or a metallurgist before using one in place of the other.
Forms & Sizes Available on M-EX
UNI 7845 42CrMo4
Round Bar → (2 listings)
Diameter: 50–50 mm (1.97–1.97 in)
Length: 5000–6300 mm (196.85–248.03 in)
GOST 4543 12HN3A
Round Bar → (2 listings)
Diameter: 50–50 mm (1.97–1.97 in)
Length: 5600–6600 mm (220.47–259.84 in)
On M-EX Right Now
UNI 7845 42CrMo4
2 active listings and RFQs →
GOST 4543 12HN3A
2 active listings and RFQs →
Frequently Asked Questions
What is the difference between UNI 7845 42CrMo4 and GOST 4543 12HN3A?
UNI 7845 42CrMo4 specifies P, S, Mo which are not specified for GOST 4543 12HN3A. GOST 4543 12HN3A specifies Ni which is not specified for UNI 7845 42CrMo4.
Can UNI 7845 42CrMo4 be substituted with GOST 4543 12HN3A?
UNI 7845 42CrMo4 and GOST 4543 12HN3A share some compositional similarity but differ enough that substitution should not be assumed. Review the differences above carefully, and consult the applicable standard or a metallurgist before using one in place of the other.