The material catalog

Nothing runs until you name a steel#

Phases has no default material. Ask for "a CCT diagram" or "a heat treatment" without saying which steel and you get a question back, not a run — the agent is instructed to ask which material you want and to offer a few examples such as DC04, DP600, 22MnB5 and EN13261 before it calls any simulation tool.

That is deliberate. Every result the product returns — phase fractions, hardness, a nugget diameter, a flow curve — is only as meaningful as the chemistry and the material card behind it, so the product refuses to guess one for you.

Your material can be a built-in catalog grade, a material saved in your workspace, or a chemistry you type in yourself. This page covers the first.

Ask for the live list, don't work from a printed one#

The catalog is served from a database, not from a fixed list compiled into the product. It can be larger than the reference set below, and a platform administrator can disable individual grades. So the honest way to find out what you can run today is to ask:

What steel grades do you support?

The agent calls the list_materials tool and reports what the catalog actually returns, grouped by the family each grade reports. If you have workspace materials, they come back in a separate section (see workspace materials).

To see the chemistry behind a name:

Show me the composition of 22MnB5.

Load DP600 and compare it with 22MnB5.

Comparing two materials returns a per-element table with a difference column, plus a table comparing their starting phase fractions. Taking that further into simulated behavior is covered in compare two grades.

The documented reference grades#

These twenty grades are the product's documented reference set, and they are also the catalog Phases falls back to if the live one is unavailable. They are the safest names to reach for.

The carbon column is the nominal figure the reference documentation records for each grade, not a certificate value. For the full chemistry of the card you are about to simulate, ask the agent for that grade's composition rather than working from this column.

The DC, HC and DP grades are recorded as zinc-coated sheet and the MnB press-hardening grades as AlSi-coated; EN13261 is bare. That distinction matters for spot welding, where the solver models a zinc coating but not an AlSi one — the calibrated 20MnB5 and 22MnB5 weld cases run with coating disabled for exactly that reason.

Note also that the reference set is wider than the validation set: 20MnB8, 25MnB5 and 29MnB7 are newer additions that do not appear in the published hardness-validation and kinetics-tuning tables and reuse another grade's data in places. How we validate says which grades each result set actually covers.

What each family is#

• Mild / deep-drawing (DC01–DC06). Low-carbon, high-formability body-panel steels. DC06 at 0.02% C is titanium-stabilized and near interstitial-free; its card carries an as-delivered state of 98% ferrite and 2% pearlite. That is the starting point, not the outcome — quench it fast enough and the model still predicts martensite.
• HSLA (HC260LA–HC420LA). Microalloyed structural steels. Their strength comes from Nb, Ti or V grain refinement and precipitation rather than from martensite, so they carry mild-steel carbon levels at much higher yield strength.
• Dual phase (DP450–DP780). Ferrite plus martensite, produced industrially by annealing in the intercritical range and cooling under control. Used for crash and structural parts.
• Press-hardening boron (20MnB5, 22MnB5, 20MnB8, 25MnB5, 29MnB7). Hot-stamping steels. 22MnB5 is the industry standard: austenitized, then die-quenched to nearly full martensite. The V-Gleeble hot-stamping profile austenitizes at 950 °C by default.
• Railway (EN13261). A medium-to-high carbon axle steel, kept as the product's legacy and validation grade. It is explicitly not a default; use it when you actually want a 0.40% C axle steel, not as a stand-in for "some steel".

What a "card" is#

Behind every catalog grade is a material card: an LS-DYNA-format material deck that holds the chemistry, the equilibrium phase curves, the activation energies used by the transformation kinetics, the composition correction that shifts the martensite-start temperature, and the as-delivered starting phase fractions. When you say "DC04", the simulator loads DC04's card and runs against it.

Cards are content-addressed and integrity-checked. Each one is verified against its registered deck and chemistry hashes the first time it is used; a card that fails verification is quarantined rather than silently replaced with something else. That is why a grade can exist in the catalog and still not be runnable — and why the product reports which state it is in instead of guessing.

Being in the catalog is not the same as being calibrated for a given physics. Catalog membership gives you a verified definition and a verified card; whether transformation kinetics, phase flow stress or a bulk flow surface are available for a particular simulator is resolved separately, at the moment you run it. See what each simulator can do with which material.

Base templates, and what "closest grade" means#

When you supply a chemistry instead of a grade name, Phases does not invent a card from nothing. It identifies the closest named steel for your benefit, then renders your chemistry onto one verified base template — an existing card that can represent every element you set to a non-zero value.

Candidates are ranked, and only enabled, verified steel cards can act as templates. If a candidate cannot represent one of your elements, it is rejected and the next candidate is tried. There is no text-patching fallback: if no template works you get No verified template can represent the requested composition. with the reason for each candidate.

The template match tells you which existing card your chemistry is being carried on. It is not a statement that the physics has been calibrated for your steel.

When your steel is not in the list#

The reference set above is automotive sheet plus one axle steel, so plenty of steels fall outside it. Ask for the live list first — the database catalog is wider than that reference set and reports families beyond these five. If your steel still is not there, give the chemistry instead of a name:

I have a steel with 0.22 C, 1.25 Mn, 0.25 Cr and 0.003 B — what is it closest to?

Load AISI 4140 chemistry: 0.40 C, 0.85 Mn, 0.25 Si, 0.95 Cr, 0.20 Mo.

Phases classifies the chemistry into a family before it searches for a nearest grade, and the family rules are blunt and worth knowing:

A trace boron addition therefore routes your steel into the press-hardening family before any distance is computed, so state boron explicitly if your steel has it. Write it as B; Phases maps it onto the card's historical Bo label for you.

If you already know which grade you want as the base, name it and the override together — Load DC04 with C = 0.15 and Mn = 1.2 — rather than leaving Phases to infer the base from the chemistry alone. What happens next, including the confirmation step and what confirming does and does not create, is covered in using your own chemistry. If you want the chemistry to persist beyond one conversation, save it as a workspace material.

Coverage is not uniform across simulators#

Heat treatment and CCT can work from catalog cards broadly, but the two other simulators are narrower:

• Resistance spot welding needs validated bulk electrical, thermal and mechanical properties and runs only on the twenty grades listed in the table above. Any other grade is refused before the solver starts. See resistance spot welding.
• V-Gleeble deformation modes (hot tensile, hot compression, Satoh) need a bulk flow-stress table for the grade. Thermal modes do not. See virtual Gleeble.

The full picture is in the capability matrix, and the honest account of where the models are weak is in known limits. If a term on this page is unfamiliar, the glossary defines the vocabulary the product uses.