Material Certificates in a CNC RFQ: MTC, CoC and Lot Traceability

The same grade can be purchased in different product forms, delivery conditions and documentation levels. If an RFQ names only the grade and a heat-linked certificate is requested after delivery, the purchased stock may not carry the right document or the link from heat number to finished parts may already have been lost. A late PDF cannot recreate broken traceability. Treat the certificate as part of the purchase specification: identify document type, standard and edition, required data, marking method and delivery timing. This lets the machine shop select the right source, segregate lots and quote the real workload.

The table distinguishes common roles. The contract, product standard and issuing authority ultimately determine the record's meaning.

ISO 10474:2013 covers inspection documents for steel products supplied against order requirements. ISO 404:2013 provides general technical delivery requirements and recognizes that the order or product standard can take precedence. EN 10204:2004 is commonly cited for metallic-product inspection documents; if type 3.1 or 3.2 is required, say so explicitly rather than requesting a “full certificate.” Do not assume the same scheme is available for every non-ferrous metal, engineering plastic or stock source. Contracting parties should use the official standard edition referenced by the order.

A PDF showing the right grade does not prove that parts in a box came from that heat. Traceability begins with identified stock and continues through blank cutting, work in progress, outside processing, inspection and packing. When a bar or plate is subdivided, an agreed method must transfer identification without mixing lots. If multiple heats are used, delivery records should map parts or groups to the applicable heat. Order-, lot- and piece-level traceability have different effort and cost; choose the level that matches risk.

Detailed documentation is often appropriate when material affects safety, strength, high-temperature or corrosion performance, regulatory obligations or customer approval. It also matters before heat treatment when chemistry and condition influence the result. Applying the same test-document package to every non-critical part can restrict sourcing and increase cost without improving function. Engineering or quality should identify the real control objective: grade, condition, chemistry, mechanical properties, origin or only a conformity declaration.

State the full grade and standard, product form and delivery condition, document type under ISO 10474 or EN 10204 where applicable, mandatory data, heat/lot traceability, marking or packing rules, approval before substitution, treatment records and digital delivery format. If the document type is uncertain, explain the control objective and resolve it before stock purchase. Never cite a certificate code without confirming that it applies to the product form and material standard.

• Grade, standard, product form and condition
• Certificate type, standard edition and mandatory data
• Order-, lot- or piece-level traceability
• Substitution and approval rules
• Treatment and inspection records

Within a confirmed order scope, VietTech can plan stock procurement, preserve lot identification during CNC machining, perform appropriate inspection and compile agreed supplier or specialist-partner records. Mill, distributor, laboratory and processor certificates must be issued by the responsible organization; VietTech does not replace that issuer or invent test results. Specialized heat and surface treatments are coordinated with partners when agreed. Availability of each document type must be confirmed in the quotation before purchase.

References include the official ISO pages for ISO 10474:2013 and ISO 404:2013 and BSI pages for BS EN 10204:2004 and BS EN 10168. This is RFQ guidance, not legal interpretation or a reproduction of copyrighted standards. The contract, product standard, industry rules and official applicable edition take precedence.