What an MTR is
A material test report, or mill test report (MTR), is the document a mill or foundry issues with a heat or lot of material. It states the grade, the heat number, the chemical analysis and the test results. In Europe it is often called a mill test certificate (MTC) or inspection certificate. EN 10204 sets the certificate types, such as 2.2, 3.1 and 3.2, which say who checked the results and how independent they are.
What to check, field by field
| Field | What to check |
|---|---|
| Issuer and certificate type | Mill or foundry named; EN 10204 type as the PO asks; signed by the right party. A 3.2 also needs the purchaser's or third-party inspector's sign-off. |
| Material standard and grade | Standard, grade and, where the PO gives one, edition. Dual-certified grades should list both. |
| Product form and size | Plate, bar, forging, casting or pipe, and the size range, match the part. |
| Heat number (and lot) | Matches the marking on the material and your heat list. |
| Chemical analysis | Every element the standard and the PO limit is reported and within range, including any extra limits in your specification. |
| Mechanical tests | Tensile, yield, elongation and reduction of area meet the grade and any PO minimums. |
| Impact tests | Charpy tests at the temperature the order asks for, with the right specimen size and acceptance values. |
| Hardness | Reported where required, for example for sour service under NACE MR0175 / ISO 15156. |
| Heat treatment | Condition and treatment, such as normalised or quenched and tempered, as the grade and PO require. |
| Supplementary tests | Any extra test the PO calls for, such as ultrasonic testing, intergranular corrosion or positive material identification. |
Check against the order, not just the standard
Most MTR tools and distributor guides check a certificate against the grade. That is necessary but not enough for engineered equipment. The customer's specification often tightens the grade: lower carbon equivalent, impact tests at a colder temperature, a hardness cap, a 3.2 certificate or extra tests. Read the requisition, the specification and your agreed deviation list before you accept a certificate.
Tie the heat number to the part
A good certificate is only useful if you can show it belongs to the part. Check the heat number on the certificate against the heat list, the bill of materials line and the marking on the part. If the material was cut, check the number was transferred to every piece. See heat number traceability.
Common MTR problems
- Certificate type lower than the PO asks for, such as 3.1 when 3.2 was ordered.
- Impact tests at the wrong temperature, or missing.
- Heat number that does not match the part marking or heat list.
- Grade correct but standard edition older than the specification requires.
- A distributor's certificate of conformity with no copy of the mill's certificate behind it.
- Values reported but one element outside a tighter project limit.
What to do when a certificate fails
Quarantine the material and raise a nonconformance. Ask the supplier for a corrected or supplementary certificate if the issue is paperwork. If the material itself fails, the options are retest where the standard allows it, use under an approved concession from the customer, or reject. Never edit or annotate a mill certificate yourself.
Where the MTR ends up
Accepted certificates go into the materials section of the manufacturing record book, usually with a material traceability list. They are also a common item on supplier submissions that the customer reviews during the order.
Doing it with OdysseyGPT
The Material Certificate Review (beta) reads each certificate and checks it against the purchase requirements, the material specification and the bill of materials. It checks grade, heat number, chemistry, mechanical tests, heat treatment, supplementary tests and EN 10204 type, and cites every conflict. The Material Traceability Check (beta) follows the chain from tag to certificate. A quality engineer accepts or rejects each certificate. For tools aimed at mills and stockists, see MTR review software.
These tools are in beta
The Material Certificate Review and Material Traceability Check are in beta. You can request access, and we onboard each team ourselves. Every finding cites the page, sheet or cell it came from, and your engineers decide what to do with it.