Key points
- A certificate is only as useful as its link to the received lot: part number, drawing revision, melt or lot ID.
- EN 10204 3.1 carries results from specific inspection, validated by an inspector independent of manufacturing.
- EN 10204 2.2 carries results, but they may come from products other than those supplied.
- A356.0 is a casting designation; A356.1 and A356.2 are ingot designations.
- A management-system certificate is not a material certificate and does not provide part-specific material or dimensional proof.
- Chemistry does not prove soundness, dimensions, heat treatment or mechanical properties.
EN 10204 document types in plain words
| Type | What it contains | Who validates it | Tells you about your parts? |
|---|---|---|---|
| 2.1 | Declaration of compliance with the order; no test results. | Manufacturer. | A declaration only. |
| 2.2 | Declaration with test results from non-specific inspection. | Manufacturer. | Results may not come from supplied products. |
| 3.1 | Declaration plus results from specific inspection on products to be supplied or their test units. | Manufacturer's authorized inspection representative, independent of manufacturing. | Inspection specific to products to be supplied. |
| 3.2 | Declaration plus test results, prepared jointly. | Manufacturer's independent inspection representative together with the purchaser's representative or the official inspector. | Inspection specific to products to be supplied, with a second party involved. |
Name the document type in the purchase order. A 2.2 result comes from the manufacturer's own procedures on products of the same specification and process, not necessarily the ones supplied; specific inspection is done before delivery on the products to be supplied or their test units. A 3.1 certificate may include results from incoming products such as ingot only if the manufacturer operates traceability procedures and can provide the corresponding inspection documents. A management-system certificate covers the named legal entity and listed locations, not a brand name alone, and gives no material or dimensional proof per part. Ask for the material certificates and inspection records themselves; see the management-system certificate and scope page.
Ingot certificate or casting analysis
In the Aluminum Association system, A356.0 is the casting designation; A356.1 and A356.2 are ingot designations. A356.2 is the ingot with the tightest limits, particularly on iron, so the casting lands inside A356.0 limits with margin after remelting picks up iron. "A356.2-T6" on a drawing usually means a casting poured from A356.2 ingot and heat treated to T6. For A356.0, chemistry is checked on the casting or melt; for A356.2, on the ingot certificate.
An ingot certificate supports traceability but does not answer every finished-part requirement. It describes the ingot lot, not the melt poured into your parts; a chemistry result describes the sample analyzed. If the drawing says A356.2, decide whether you specify the ingot, the casting, or both, and how each is evidenced. State the governing standard and edition, for example ASTM B26/B26M for sand or ASTM B108/B108M for permanent-mold castings; a squeeze casting is often ordered to one of them by agreement, or to a customer specification. Drawing note example: "Material: A356.0-T6 per ASTM B108/B108M-[edition], cast from A356.2 ingot." See the A356 and A356-T6 casting specification guide.
Checking the certificate line by line
The limits below are the A356 reference limits published on this site; confirm them against the governing standard on your drawing.
| Line on the certificate | What to check | Why it matters |
|---|---|---|
| Identification | Manufacturer, part number, drawing revision, melt or lot ID | Ties the result to your order and lot records |
| Standard and edition | The standard and edition the drawing cites | Limits come from the cited standard; ASTM B26 is tighter on iron, zinc and manganese than die-casting practice limits |
| Grade and product form | A356.0 casting, A356.2 ingot, or both | A .0 suffix is a casting; .1 or .2 is an ingot |
| Silicon | 6.5–7.5% | Every specified element is checked, minimum and maximum |
| Magnesium | 0.20–0.45% | Magnesium makes the alloy respond to T6 |
| Iron | ≤ 0.2% | Remelting picks up iron; A356.2 ingot leaves margin for it |
| Copper | ≤ 0.2% | Low copper keeps corrosion behavior good when bolted to a dissimilar metal |
| Other elements | Mn ≤ 0.1%, Zn ≤ 0.1%, Ti ≤ 0.2%, plus residuals and totals | A blank line cannot be checked |
| Condition, method, signature | T6 stated; analysis method; name and position of the validator | Chemistry does not show the heat-treatment condition |
Values must be printed next to the limits they are judged against; a certificate with only "conforms", typical values or a result with no limit cannot be checked line by line.
When the certificate names a different alloy or a wider range
Equivalence has distinct parts: naming correspondence, chemical conformity, application suitability. A supplier can show naming correspondence without the other parts. Chemical conformity means the proposed grade meets every composition limit of the original requirement, compared element by element, minimum and maximum, including residuals and totals.
AlSi9Cu3(Fe) is EN AC-46000 in EN 1706; usual counterparts A380 (ASTM), ADC10 (JIS) and YL112 (GB) are close, not identical because copper, iron and zinc ranges differ. It is used as cast and is not heat treated to T6. Copper raises strength in die-casting alloys such as A380, AlSi9Cu3 and ADC12 but lowers corrosion resistance; for water, coolant or outdoor service, low-copper alloys such as A356, A360 and AlSi10Mg are evaluated first.
With a wider grade range, a sample inside the drawing limit does not prove future lots ordered to the wider grade will stay there. Write the limit into the supply requirement with verification and change control, or qualify a revised requirement. The alloy substitution approval checklist shows how to compare limits element by element; alloy selection for pressure-tight castings covers copper and corrosion. Record the decision: approve within a defined scope, authorize qualification only, or reject.
Linking the certificate to the delivered lot
A lot can be one melt, one heat-treatment batch, one die or cavity, one shift or a date range; a sample represents only its population. Ask for composition per melt, with alloy and condition on the report and the report tied to the melt or lot.
For a new part, the first-article package includes composition of the melt, dimensional and mechanical results, and traceability to tool, cavity and lot; see the first-article inspection package. For production, see lot release sampling, which sets composition checks per melt alongside the other characteristics.
You may order an independent check analysis on delivered parts at a laboratory of your choice, and agree beforehand which result governs if the two differ. If a mechanical result is below requirement, chemistry is one step in the check order: specimen location, fracture surface, heat-treatment batch record, chemistry with magnesium and iron against limits, test method and machine calibration.
What a material certificate does not prove
- Internal soundness: shrinkage and gas porosity need a volumetric check such as X-ray, not a chemistry report.
- Leak tightness: pressure-tight parts need their own leak-test records where required.
- Dimensions and heat-treatment condition: T6 needs its batch records, and hardness is a quick lot check, not a design value.
- Mechanical properties: results on the agreed specimen basis, with specimen type, location and condition.
- Component performance: a coupon result does not replace component testing for a loaded or safety-relevant part.
How CEX documents material
Incoming ingot is checked before melting, and the melt is verified by optical emission spectrometry per heat, so the pour is confirmed, not assumed (company-reported). Mechanical properties are tested on specimens when the drawing or standard requires them, and hardness is checked after heat treatment, using the tensile testing machine and hardness tester in our in-house inspection lab (company-reported). Acceptance comes from the buyer's drawing and specification; equipment alone does not define it.
The company behind CEX Casting is Qingdao Dechengxin Metal Products Co., Ltd., which holds ISO 9001:2015 and IATF 16949:2016 in its own name; the IATF scope is manufacturing of aluminium alloy die-cast parts, with clause 8.3 product design excluded. CEX is a combined factory and trading company: Dechengxin is the factory, and Qingdao Chengenxin is the trading company under the same owner.
Before you send an inquiry, put the following on the drawing or the order: alloy and product form, governing standard and edition, document type, lot or melt link, and any independent check analysis you plan to run. The casting RFQ checklist sets out the rest of the enquiry package, including the records to request.