65G, 65Mn4, 66Mn4, 1.1240, 1.1260 - Manganese spring alloy structural steel according to PN-74/H-84032

 

Standard Steel Grade
Chemical Composition %
C: Mn: Si: P: S: Cr: Ni: Al: Cu:
PN 65G
0.6 - 0.7 0.90 - 1.20 0.15 - 0.40 <0.04 <0.04 <0.3 <0.3 - <0.25
DIN 66Mn4 - 66 Mn 4 - 1.1260
0.60 - 0.71 0.85 - 1.15 0.15 - 0.30 <0.035 <0.035 - - - -
DIN 65Mn4 - 65 Mn 4 - 1.1240
0.60 - 0.70 0.90 - 1.20 0.25 - 0.50 <0.035 <0.035 - - - -
ISO 56Mn4 - 56 Mn 4 - 1.1233
0.52 - 0.60 0.90 - 1.20 <0.40 <0.025 <0.03 - - <0.05 <0.3
GOST 65G - 65Г
0.62 - 0.70 0.90 - 1.20 0.17 - 0.37 <0.035 <0.035 <0.25 <0.25 - -
GOST 65GA - 65ГА
0.65 - 0.70 0.7 - 1.0 0.15 - 0.30 <0.025 <0.025 <0.15 <0.2 <0.08 <0.2
STAS 65MN10 - 65 Mn 10
0.62 - 0.70 0.90 - 1.20 0.17 - 0.37 <0.035 <0.035 <0.3 <0.3 - <0.3
ČSN / STN ČSN 13 180 - ČSN 13180
0.70 - 0.80 0.90 - 1.20 0.15 - 0.35 <0.035 <0.04 <0.3 <0.4 - <0.3
SAE AISI C1062 - 1062
0.54 - 0.65 0.85 - 1.15 - <0.04 <0.05 - - - -
UNS AISI 1066 - AISI 1566
0.60 - 0.71 0.85 - 1.15 - <0.04 <0.05 - - - -

 

65G steel - specification and application

65G - Steel for leaf springs and springs with low hardenability requiring increased resistance to abrasion for rings, valve springs, flat, coils and spring washers with small cross-sections and loads. Steel for hardening in oil insensitive to temper brittleness. Steel does not show resistance to corrosive environments.


Mechanical and physical properties of 65G steel

  • Tensile strength, Rm ≥ 980 MPa
  • The yield strength, Re ≥ 780 MPa
  • Contraction, Z ≥ 30%
  • Elongation, A ≥ 8%
  • Hardness after softening ≤ 241 HB
  • Hardness in raw condition: ≤ 262 HB
  • Hardness after hardening and tempering in a temp. of 380-520℃ = 42 - 47 HRC
  • Hardness after hardening and tempering in 400 - 550 ℃ = 310 - 350 HB
  • Density ρ = ~ 7,83 kg / dm3
  • Thermal conductivity λ20 ℃ = ~ 46,2 W ⋅ m-1 K-1
  • Thermal capacity cp20-100 ℃ = ~ 481 J ⋅ kg-1 K-1
  • Linear expansion coefficient α20-100℃ = ~11,35 10-6 K-1

 


In the described grade, the company provides:

 


The list of equivalents and other designations of 65G steel:

66Mn4, 66 Mn 4, 1.1260, 65Mn4, 65 Mn 4, 1.1240, 56Mn4, 56 Mn 4, 1.1233, 65Г, 65GA, 65ГА, 65MN10, 65 Mn 10, ČSN 13 180, ČSN 13180, AISI C1062, 1062, AISI 1066, AISI 1566