Establish exactly what is being replaced
When a supplier offers an "equivalent" alloy, ask for a documented substitution review before you change the purchase specification. A cross-reference chart can name a candidate; it cannot show that the proposed material meets your drawing, route and finished-part requirements. Copy the complete material requirement from the released drawing: standard and edition, grade, product form, casting route, condition and any customer limits. Ask for the proposal in the same fields.
Product form matters. In the Aluminum Association system a .0 suffix designates a casting and .1 or .2 an ingot, and the Pink Sheets set registered composition limits. An ingot certificate supports traceability but does not answer every finished-part requirement.
Three kinds of equivalence
- Naming correspondence: two names appear together in a reference table.
- Chemical conformity: the proposed supply meets every composition limit of the original requirement.
- Application suitability: the finished part meets its performance and acceptance criteria with the new material and process.
A supplier can show the first without the other two. Casting properties depend on both composition and the casting process, and regional designation systems differ, so keep the full specification during the comparison.
Side-by-side worksheet
A proposed purchasing control, not a material standard. Do not leave a blank cell to mean "same": mark each line unchanged, different or unresolved, with a document reference.
| Review item | Original requirement | Evidence for the proposal |
|---|---|---|
| Governing documents | Drawing, order, standard edition, supplements | Exact proposed documents and a list of differences |
| Product form and grade | Complete designation | Casting vs ingot, exact grade |
| Chemistry | All element limits incl. residuals and totals | Element-by-element limit comparison, representative analysis |
| Route | Approved process and operations | Proposed route and qualification impact |
| Condition | As-cast or heat treated | Condition and process records |
| Mechanical | Properties and basis of measurement | Method, specimen origin, location, condition, results |
| Application | Sealing, corrosion, thermal, dimensional | Defined tests and acceptance evidence |
| Traceability | Lot identification, change authorisation | Link between records, lots and the approved specification |
Compare limits, not one favourable result
Request minimum and maximum values from both specifications and check every required element. If the proposed grade allows a wider range for an element than your drawing, a sample inside your limit does not prove that future lots ordered to the wider grade will stay there. Either write your limit into the supply requirement with verification and change control, or qualify a revised requirement.
Commonly cited equivalents for three die casting alloys
The three alloys we are asked about most are AlSi9Cu3, AlSi10Mg and A383. The table lists the designations commonly cited as equivalent material in each system. Treat every row as a naming correspondence to be checked against the standards, not as proof of chemical conformity; the limits differ between systems, and some cross-references in circulation pair one alloy with two different neighbours.
| Alloy | EN / ISO | ASTM / UNS | JIS | GB |
|---|---|---|---|---|
| AlSi9Cu3(Fe) | EN AC-46000 | Closest: A380.0 (UNS A13800) | Closest: ADC10 | Closest: YL112 |
| AlSi10Mg | EN AC-43400 (die casting, Fe); EN AC-43000 | Closest: A360.0 (UNS A13600) | Closest: ADC3 | Closest: YL104 |
| A383 | Closest: EN AC-46100 / 46000 family | A383.0 (UNS A03830) | Closest: ADC12 | Closest: YL113 |
AlSi9Cu3 equivalent material
AlSi9Cu3(Fe) is the European general-purpose die casting alloy, EN AC-46000 in EN 1706. Its usual North American counterpart is A380; in Japan, ADC10; in China, YL112. They share the Al-Si-Cu family but are not identical: copper, iron and zinc ranges differ, and the Fe in the EN name marks the higher-iron die casting variant.
- Chemistry to compare: copper, zinc, iron and the impurity totals
- What to test: composition to the original limits, corrosion if the part is exposed, and the leak test if sealing
- Do not heat treat to T6: like A380, it is used as cast
AlSi10Mg equivalent material
AlSi10Mg is a low-copper Al-Si-Mg alloy. For die castings, EN AC-43400 is the high-iron variant; EN AC-43000 is the general casting grade. The closest North American alloy is A360; in JIS it is usually paired with ADC3, and some charts list ADC10, which is a copper-bearing alloy and cannot be equivalent to both AlSi9Cu3 and AlSi10Mg. In GB it is usually paired with YL104.
- Chemistry to compare: copper (low in AlSi10Mg), magnesium, iron
- What to test: corrosion behaviour where low copper was the reason for the choice; elongation if specified
- Heat treatment: only on a qualified route; blistering is a risk on conventional die castings
A383 equivalent material
A383 is A380 adjusted with higher silicon for better die filling and lower hot-cracking tendency in thin, complex parts. Its usual Japanese counterpart is ADC12 and its Chinese one YL113. European charts point to the AlSi11Cu or AlSi9Cu3 grades, which differ more. We also run A383 as a squeeze casting for an engine mount bracket.
- Chemistry to compare: silicon, copper, iron and zinc against A383.0
- What to test: composition, filling of thin sections, and the drawing's mechanical requirement on the agreed specimen
- When ADC12 is offered for A383: check the copper and silicon limits line by line
Match property evidence to the component
Headline tensile values from different conditions or specimens are not comparable. Record specimen origin, location and condition next to each value. ASTM B85/B85M covers general-purpose aluminum die castings and cautions that it may not address the verification needed for highly loaded or safety-critical parts, so citing it does not close project-specific performance questions.
Record one of three decisions
- Approve within a defined scope. Part, revision, supplier, material requirement, process, lots; what triggers another review.
- Authorise qualification only. Named samples or trial, with production release on hold and open tests listed.
- Reject or return. State the unmet requirement or missing evidence.
Alloy selection for pressure-tight castings Casting inspection plan