What is a heat number on metal?
A heat number is a unique identifier assigned to a batch of metal produced in a single melting operation. It links the material to its mill test report for full traceability.
Related Terms
Mill Test Report(MTR)
A mill test report (MTR) is a quality document provided by a metal manufacturer that certifies the chemical composition and mechanical properties of a batch of metal. Required for aerospace, defense, and many industrial applications.
Certificate of Conformance(CoC / C of C)
A certificate of conformance (CoC) is a document from a supplier declaring that a product meets the required specification or standard. Often required alongside an MTR for regulated industries.
ASTM(ASTM)
ASTM International publishes voluntary consensus standards for materials, products, and testing. ASTM grades like A36, A108, and A500 define the chemical and mechanical requirements for steel products.