An MTC, or Certificate of Conformance (CoC), is a legal document from the steel producer that provides verified data for a specific batch of material. It is vital for quality assurance and traceability.
Typical Contents:
Supplier name, customer name, purchase order details.
Material Description: Grade (AISI 4140), condition, dimensions.
Traceability Codes: Heat Number and Batch/Lot Number.
Chemical Analysis: Actual results for all elements, confirming compliance.
Mechanical Test Results: Actual tensile, yield, elongation, hardness, and impact values from tested samples.
Statement of Conformity: A declaration that the material meets the specified standard (e.g., ASTM A322).
This document must accompany the material shipment and be retained for the life of the component, especially in regulated industries.