Reading CNC Material Data: Grade, Temper and Test Conditions

A material property belongs to a specified material condition and test context. The alloy name alone is insufficient. Record the grade, temper, product form, relevant dimensions, units and whether the number is a typical value or a specified limit before comparing datasheets. The two 6061 documents below illustrate why these qualifiers matter. Kaiser table · Hydro table and footnotes

Separate designation, condition and product form

The material designation identifies the named material; the supplied condition records its processing state. Product form identifies what is supplied, such as sheet, plate or an extruded profile. These fields describe different things and should remain separate in a property record.

For example, Hydro lists 6061 together with several temper designations. T6 and T6511 are grouped as solution heat-treated and artificially aged, with its footnote further identifying T6511 as stress-relieved by stretching. The shared alloy number does not erase those condition details. Hydro temper definitions, p. 1

A compact example of unlike data

These entries are not a ranking of suppliers or interchangeable design inputs. One table reports typical properties; the other specifies minimum levels. Their product forms and condition designations differ. Do not average the numbers or treat the higher number as a guaranteed property of every 6061 part. The original documents also contain specimen and cross-section qualifications. Kaiser, p. 1 · Hydro, p. 2

Fields to retain when transcribing a value

As an editorial reference format, record:

• Material designation and the exact supplied condition.
• Product form and the applicable thickness or cross-section range.
• Property name and unit, including the definition used for yield strength.
• Test basis and specimen qualification where provided.
• Statistical meaning: typical, minimum, maximum or range.
• Source version, table location and any limiting footnote.

Keeping this information beside the number makes it possible to revisit the comparison when a source or purchase specification changes.

Use the data for the right question

The example demonstrates how to read a table. It does not establish a permissible stress, fatigue requirement or substitution rule for a component. A buyer’s required material specification and the delivered batch documentation need their own checks. Machining a component from an alloy does not itself validate that the supplied stock meets the design’s material requirement.

Limits and related tasks

The Kaiser document is a historical revision and the Hydro document identifies its own revision. Confirm the applicable purchase specification and current documentation before ordering. Use the CNC RFQ checklist to state the material and condition explicitly rather than requesting only “aluminium”.