Enter mechanical, chemical, and physical data from a mill test report (MTR) to determine whether the steel is acceptable for cold-formed-steel construction under AISI S100-16 (Section A3, Applicable Steels & Other Steels). The tool will categorize the material into one of the four S100 acceptance pathways, recommend design values Fy/Fu, suggest likely matching ASTM specifications, and screen weldability via carbon equivalent.
MTR mode: enter actual measured properties from your test report. The tool will (a) check ductility against AISI S100 floor values, (b) recommend a design Fy/Fu, and (c) suggest ASTM grades whose specified minimums your steel satisfies.
| Property | From MTR | For design | Basis |
|---|
| Check | Limit / criterion | Computed | Result |
|---|
| Specification | Grade | Min Fy | Min Fu | Min elong. | Chem | Fit |
|---|
Section A3 of the North American Specification for the Design of Cold-Formed Steel Structural Members (AISI S100-16, reaffirmed 2020, with S3-22) governs which steels may be used. There are four acceptance pathways that this tool checks in order:
Ductility floor (A3.2.1 / A2.3.1). Tensile/yield ratio Fu/Fy ≥ 1.08 and elongation ≥ 10% (2″ gauge) or ≥ 7% (8″ gauge). Steels not meeting this floor can sometimes qualify under A3.2.1 item (b) or the new item (c) (S3-22) with restricted use — the tool flags this case for engineer review rather than auto-approving.
Unidentified steel. If you select None for documentation, the tool defaults to the legacy unidentified-steel treatment: Fy capped at 25 ksi (172 MPa) for design, no Fu credit, and recommends not using the material in load-bearing applications without testing every coil.
The candidate-spec list is generated by checking whether your reported Fy, Fu, and elongation meet (i.e. equal or exceed) the specified minimums of each grade in the internal database, filtered by your selected product form and coating. A "fit" rating reflects how close the actual values are to the minimums — a tight fit suggests a likely match, a loose fit suggests the steel is over-strength for that grade (so it could be that grade, but could just as easily be a higher one). Spec matching is informational only. Final certification against a specific ASTM standard requires that the full chemistry, coating, dimensional, and process requirements of that standard also be met — not just the mechanical minimums.
When you enable welding and provide chemistry, the tool computes the IIW
carbon equivalent: CE = C + Mn/6 + (Cr + Mo + V)/5 + (Cu + Ni)/15.
Practical thresholds applied: CE ≤ 0.40 — readily weldable,
no preheat normally required; 0.40 < CE ≤ 0.45 — acceptable
with attention to procedure; 0.45 < CE ≤ 0.55 — preheat
typically required; CE > 0.55 — specialized procedure required.
AWS D1.3 (sheet steel) generally targets C ≤ 0.15% and CE in the
lower band; D1.1 covers heavier sections.
The optional hardness sanity check uses standard ASTM E140 conversions (HRB and HV converted to HB) and the empirical relation Fu [ksi] ≈ 0.5 × HB (valid for HB < 350, i.e. essentially all CFS feedstock). A delta of more than ±15% between reported Fu and the hardness-implied Fu is flagged for retest. The correlation is indicative, not certifying.
Disclaimer. Results are intended as a preliminary reference. Values and classifications must be verified against the governing code edition and a licensed engineer's project-specific review before being used for structural design or material acceptance. Scottsdale Construction Systems assumes no liability for the use of these values.
ScotCalc · CFS Material Compliance Checker · © Scottsdale Construction Systems