Measured standard-probe cooling curves
Describes the medium response for the stated probe and test conditions. It is not the surface or core curve of a production workpiece.
Carbon equivalent calculator
Organise steel composition indices for welding, respecting each formula’s application.
This page calculates CE(IIW), Pcm and CET. Enter mass percentages from the material certificate and select the formula appropriate to the project material and welding specification.
CE(IIW)
=
C
+
Mn/6
+
(Cr+Mo+V)/5
+
(Ni+Cu)/15
IIW • C > 0.12% carbon & low-alloy steels
Pcm
=
C
+
Si/30
+
Mn/20
+
Cu/20
+
Ni/60
+
Cr/20
+
Mo/15
+
V/10
+
5B
Ito-Bessyo • C ≤ 0.12% low-carbon & pipeline steels
CET
=
C
+
(Mn+Mo)/10
+
(Cr+Cu)/20
+
Ni/40
ThyssenKrupp
Input Parameters
Composition (wt%)
Preset:
C
0.01 – 0.80
Mn
0 – 2.00
Si
0 – 1.50
Cr
0 – 3.00
Ni
0 – 4.00
Mo
0 – 1.50
Cu
0 – 1.00
V
0 – 0.50
B
0 – 0.005
Calculation Results
CE (IIW)
0.500
wt%
Pcm (Ito-Bessyo)
0.340
wt%
CET (ThyssenKrupp)
0.380
wt%
Weld Cracking Risk (CE(IIW) based)
0.0
0.4
0.5
0.6
0.8
1.0+
Fair — Some precautions needed
Moderate precautions. Preheat 100–200°C recommended.
Recommended: CE(IIW) (C = 0.20% > 0.12%)
Calculate DI from this Composition
References: CE(IIW): IIW Recommendation Doc. IX-536-67 · Pcm: Ito Y., Bessyo K. (1968) · CET: ThyssenKrupp Stahl AG
Risk thresholds based on AWS D1.1 and EN 1011-2. CE(IIW) not suitable for boron-containing steels; use Pcm instead.
Risk thresholds based on AWS D1.1 and EN 1011-2. CE(IIW) not suitable for boron-containing steels; use Pcm instead.
How to use the tool and get product support
Three indices are not three identical conclusions
CE(IIW) is commonly used in steel weldability assessment; Pcm is used in applications including low-carbon low-alloy steels; CET serves its corresponding welding assessments. Coefficients and scope differ, so a single carbon-content threshold cannot decide every project’s formula.
What else must be considered?
Cold-cracking assessment also involves diffusible hydrogen, thickness or combined thickness, restraint, heat input, preheat and interpass temperature. A carbon equivalent alone cannot specify preheat for every joint.
How this differs from the quenching tools
This is not a cast iron carbon-equivalent formula or a calculator for as-quenched hardness, quenchant H or cooling curves.
For steel hardenability, use DI or Jominy tools. For quench cooling problems, discuss Anran quenchants and testing equipment.
Data classification
Three data types must remain separate
Every curve and conclusion on this site is identified by how the data was obtained.
Software-predicted curve
Calculated from a stated model and inputs. It is a prediction, not measured production data.
Measured internal workpiece cooling curves
Comes from internal points in the actual workpiece and is used to assess the real cooling process against post-quench hardness, microstructure and properties.
Unless explicitly identified and validated, one data type cannot be converted into or substituted for another.Read the technical method
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