Carbon Equivalent Calculator
Carbon Equivalent Calculator (CE, IIW) · Weldability Check
Enter chemistry (wt%) to calculate CE using the standard IIW formula and get a quick weldability assessment.
Chemical composition (wt%)
All values are mass percent (%). Leave unknown elements as 0.
Results
Carbon Equivalent (CE, IIW)
—
Formula: CE = C + Mn/6 + (Cr + Mo + V)/5 + (Ni + Cu)/15Weldability assessment
—
Enter composition to assess weldability.CE range guide
—
Common practical thresholds (starting point, not absolute rules).What This Carbon Equivalent Calculator Does
Carbon equivalent (CE) converts multiple alloying elements into a single number that helps teams communicate weldability risk quickly. For carbon and low-alloy steels, CE is often used as an early checkpoint before welding procedures are finalized.
Carbon Equivalent Formula (IIW)
This page uses the standard IIW formula: CE = C + Mn/6 + (Cr + Mo + V)/5 + (Ni + Cu)/15. Inputs are wt% from your MTC or chemistry report.
Understanding CE Ranges (Practical Guidance)
Mobile tip: swipe left/right to view the full table.
| CE range | Weldability | Typical meaning (guidance) |
|---|---|---|
| ≤ 0.40 | Good | Often weldable with standard practice; preheat may not be required for normal thickness. |
| 0.40 – 0.45 | Fair | Preheat may be needed on thicker sections or restrained joints; control heat input. |
| 0.45 – 0.60 | Crack-sensitive | Higher hydrogen cracking sensitivity; tighter control on consumables, heat input, and preheat. |
| > 0.60 | High risk | High cracking risk; special welding procedures and strict controls are typically required. |
Examples (Quick Checks)
Example A (structural steel): C=0.18, Mn=1.20, Cr=0.20 → CE ≈ 0.42 → Fair weldability.
Example B (pressure vessel grade): C=0.12, Mn=1.00, Mo=0.20 → CE ≈ 0.33 → Good weldability.
Example C (higher alloy / higher strength): If CE exceeds 0.60, treat as high cracking sensitivity and plan controls accordingly.
How LYHSteel Supports Welding-Critical Projects
For projects where weldability is critical, LYHSteel can support steel supply plus quality checks and documentation alignment. Share your target grade, thickness, and welding constraints—we can quote with practical sourcing and inspection support.
FAQ
1) Is CE enough to confirm weldability?
CE is a fast indicator, but final decisions should follow your WPS and applicable codes, considering thickness, restraint, heat input, and hydrogen control.
2) Which steels is CE (IIW) best suited for?
CE (IIW) is commonly used for carbon steels and low-alloy steels. Stainless steels and advanced alloys may require different weldability models.
3) What if the mill certificate is missing some elements?
You can leave unknown values as 0. The result is still useful as a screening number, but treat it as conservative guidance rather than a guaranteed limit.
4) Can CE help determine preheat?
CE is often used as a first step to flag whether preheat might be necessary, but preheat should ultimately be set by procedure qualification and code guidance.
Keyword Synonyms
carbon equivalent calculator, CE (IIW) calculator, weldability calculator, carbon equivalent formula, CE value for welding, HAZ cracking risk, preheat decision guide, carbon steel weldability
