France · AFNOR NF

42 C 4

NF E 29-043

Chemical composition

wt% · log scale
0.010.1110C0.39 – 0.45Cr0.9 – 1.2Mn0.6 – 0.9Mo0.15 – 0.25P0.035S0.035Si0.1 – 0.4
  • min – max range
  • typical value

Mechanical properties

value range by condition
Yield strength Rp0.2≥515 MPaTensile strength Rm690–890 MPaElongation A≥15 %Bolts, Heat treated, M100 < d <= M180Yield strength Rp0.2≥655 MPaTensile strength Rm790–990 MPaElongation A≥13 %Bolts, Heat treated, M68 < d <= M100Yield strength Rp0.2≥720 MPaTensile strength Rm860–1060 MPaElongation A≥13 %Bolts, Heat treated, d <= M68Yield strength Rp0.2≥725 MPaYield strength Rp0.2≥725 MPaTensile strength Rm860–1060 MPaTensile strength Rm860–1060 MPaImpact energy Kv/Ku≥22 JImpact energy Kv/Ku≥28 JElongation A≥13 %Elongation A≥13 %Bolts, hot rolled or cold drawn

High / low temperature

value vs. temperature
21.323.125.026.928.7-100-50°C
  • Bolts hot rolled or cold drawn · Impact energy Kv/Ku

Chemical composition

ElementminmaxSimilarRemarks
C0.390.45
Cr0.91.2
Mn0.60.9
Mo0.150.25
P0.035
S0.035
Si0.10.4

Mechanical properties

Heat treatment / conditionYield strengthTensile strengthElongationReduction of areaImpact energyHardness
Bolts, Heat treated, M100 < d <= M180≥515690–890≥15
Bolts, Heat treated, M68 < d <= M100≥655790–990≥13
Bolts, Heat treated, d <= M68≥720860–1060≥13
Bolts, hot rolled or cold drawn≥725860–1060≥13≥22 Charpy V Notch (-100°C)；≥28 Charpy V Notch (-50°C)
nuts≥24 Charpy V Notch (-100°C)HV 248–352

High/low temperature

Impact energy Kv/Ku (J)
ConditionTemperature ℃minRemarks
nuts-10024Charpy V Notch
Bolts hot rolled or cold drawn-5028Charpy V Notch
Bolts hot rolled or cold drawn-10022Charpy V Notch

Heat treatment

Type1
Heat-treatment curveCCT modified
Heat-treatment curveHardness-Tempering
Heat-treatment curveCCT
Heat-treatment curveTTT
Heat-treatment curve淬透性