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BS 970 EN41B vs BS 970 EN40A

Related Material — 69.2% match based on chemical composition and mechanical property overlap.

BS 970 EN41B (BS 970:1955) and BS 970 EN40A (BS 970:1955) are both steel grades. Both fall under the Alloy Steel category. BS 970 EN41B is typically used for nitrided gears, crankshafts, cylinder liners, while BS 970 EN40A is commonly used for bars and billets for forging; forgings and drop-forgings; bars for machining; bright bars. suitable for 45/55 (r), 50/60 (s), 55/65 (t), 60/70 (u) tons/sq in; selection of en 40a or 40b governed by tensile range required.. BS 970 EN41B is defined under British Standards (BS), originating from United Kingdom, while BS 970 EN40A is defined under British Standards (BS), originating from United Kingdom.

As per chemical composition, BS 970 EN41B vs BS 970 EN40A is a 66.3% match. As per mechanical properties, the match is 75%. Combined, this makes them a related material overall at 69.2%.

Frequently Compared With BS 970 EN41B:
UNI 11234 100Cr6 GB/T 3077 12Cr2Ni4A GOST 4543 12HN3A NF A35-565 100C6 IS 1570 (Part 4) 10Cr20Mo6 IS 4367 07Cr4Mo6 IS 1570 (Part 4) 07Cr4Mo6 IS 1570 (Part 4) 105Cr5 IS 1570 (Part 7) 10Cr36Mo10H IS 1570 (Part 4) 103Cr4 IS 4367 10Cr9Mo10 IS 1570 (Part 4) 103Cr6
Match Breakdown
CHEMISTRY MATCH
66.3%
MECHANICAL MATCH
75%
OVERALL
69.2%
Specifications
Property BS 970 EN41B BS 970 EN40A
Standard BS 970:1955 BS 970:1955
Category Alloy Steel Alloy Steel
C (%) 0.35-0.45 0.10-0.20
Si (%) 0.10-0.45 0.10-0.35
Mn (%) <=0.65 0.40-0.65
Ni (%) <=0.40 <=0.40
Cr (%) 1.40-1.80 2.90-3.50
Mo (%) 0.10-0.25 0.40-0.70
Al (%) 0.90-1.30 Not specified
S (%) <=0.050 <=0.050
P (%) <=0.050 <=0.050
Matched by chemical composition and mechanical properties, not a formal equivalence claim. Always verify against the applicable standard before substitution.
Mechanical Properties
Property BS 970 EN41B BS 970 EN40A
Tensile Strength ≥695 MPa (45 tons/sq in, converted) ≥695 MPa (45 tons/sq in, converted)
Yield Strength ≥525 MPa (34 tons/sq in, converted) ≥525 MPa (34 tons/sq in, converted)
Elongation ≥20% ≥22%
Hardness 201-255 HB 201-255 HB
Condition Hardened and tempered R, ruling section 6 in (lowest-strength condition of the standard) Hardened and tempered R, ruling section 6 in (lowest-strength condition of the standard)
Typical Applications
BS 970 EN41B
Nitrided gears, crankshafts, cylinder liners
BS 970 EN40A
Bars and billets for forging; forgings and drop-forgings; bars for machining; bright bars. Suitable for 45/55 (R), 50/60 (S), 55/65 (T), 60/70 (U) tons/sq in; selection of En 40A or 40B governed by tensile range required.
Key Differences
Can BS 970 EN41B Be Substituted With BS 970 EN40A?
BS 970 EN41B and BS 970 EN40A 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
BS 970 EN41B
Round Bar → (3 listings)
Diameter: 50–50 mm (1.97–1.97 in)
Length: 5700–6800 mm (224.41–267.72 in)
BS 970 EN40A
No active listings currently.
On M-EX Right Now
BS 970 EN41B
3 active listings and RFQs →
BS 970 EN40A
0 active listings and RFQs →
Frequently Asked Questions
What is the difference between BS 970 EN41B and BS 970 EN40A?
BS 970 EN41B specifies Al which is not specified for BS 970 EN40A.
Can BS 970 EN41B be substituted with BS 970 EN40A?
BS 970 EN41B and BS 970 EN40A 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.