Minimal Match — 50.8% match
based on chemical composition and mechanical property overlap.
GB/T 8731 Y35 (GB/T 8731-2025) and IS 4432 10C8S10 (IS 4432:1988) are both steel grades.
Both fall under the Free Machining Steel category.
GB/T 8731 Y35 is typically used for used for screws, nuts, fittings, precision turned parts, bushings, and automatic lathe components., while IS 4432 10C8S10 is commonly used for forgings and fabrication of case-hardened machine or automobile parts.
GB/T 8731 Y35 is defined under Guobiao Standards (GB/T), originating from China, while IS 4432 10C8S10 is defined under Bureau of Indian Standards (IS), originating from India.
As per chemical composition, GB/T 8731 Y35 vs IS 4432 10C8S10 is a 73.2% match.
As per mechanical properties, the match is 6.1%.
Combined, this makes them a minimal match overall at 50.8%.
Matched by chemical composition and mechanical properties, not a formal equivalence claim. Always verify against the applicable standard before substitution.
Mechanical Properties
Property
GB/T 8731 Y35
IS 4432 10C8S10
Tensile Strength
520-680 MPa
Not specified
Yield Strength
315-420 MPa
Not specified
Elongation
10-16%
Not specified
Hardness
140-190 HB
Not specified
Core Tensile Strength
Not specified
600-850 MPa (16 mm) / 550-800 MPa (30 mm)
Core Yield Strength
Not specified
>=400 MPa (16 mm) / >=330 MPa (30 mm)
Core Elongation
Not specified
>=12% (16 mm) / >=14% (30 mm)
Core Reduction of Area
Not specified
>=35% (16 mm) / >=40% (30 mm)
Hardness, annealed (A)
Not specified
<=150 HB
Typical Applications
GB/T 8731 Y35
Used for screws, nuts, fittings, precision turned parts, bushings, and automatic lathe components.
IS 4432 10C8S10
Forgings and fabrication of case-hardened machine or automobile parts
Can GB/T 8731 Y35 Be Substituted With IS 4432 10C8S10?
GB/T 8731 Y35 and IS 4432 10C8S10 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.
What is the difference between GB/T 8731 Y35 and IS 4432 10C8S10?
Both grades share a similar composition profile; see the specification table above for the exact chemistry and mechanical property values.
Can GB/T 8731 Y35 be substituted with IS 4432 10C8S10?
GB/T 8731 Y35 and IS 4432 10C8S10 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.