Best Practices

In the course of the ongoing proficiency test program, it is probable that new information will arise that will shed light on the effectiveness of current testing practices. Properly used, this will lead to the development of improved testing practices. With a significantly large population of laboratories participating, all of whom are accredited to the highest standard, there is a unique opportunity to draw meaningful conclusions about the best methodology or nuances of technique to apply in the future.

This information might suggest ways to improve accuracy or reliability of data produced or generate new consensus positions on current requirements. Proposals for entirely new technologies might be discussed, tested and critically reviewed by the Nadcap laboratory community.

After a proposal has been thoroughly reviewed and verified by the Task Group, a suggested practices document or other appropriate reference materials will be published in this location. This will provide an added value to all participants in the Nadcap process, which is not achievable in any other forum.

This forum provides a uniquely focused place for consensus to be sought and improvements generated that serves the needs of aerospace labs, without the compromises intrinsic to technical bodies with a more general orientation.

If you would like to participate in the generation or peer review of publications, or to suggest a best practice, please contact:

Jim Lewis, Senior Staff Engineer + 1 724 772 1616 extension 8688

Jennifer Kornrumpf, CSR + 1 724 772 1616 extension 8680

Accepted Best Practices for Interlaboratory Prociency Testing Program

CHEMISTRY

Nickel Base Alloys, Cobalt Base Alloys, High Alloy Iron Base Alloys
• Major Elements and Minor Elemental Constituents – XRF
• Trace Elements – Graphite Furnace Atomic Absorption, ICP

Low Alloy Iron Base, Titanium Base Alloys
• Major Elements and Minor Elemental Constituents – XRF, OES
• Trace Elements – Graphite Furnace Atomic Absorption, ICP

Aluminium Base Alloys
• Major Elements and Minor Elemental Constituents – XRF
• Trace Elements – Graphite Furnace Atomic Absorption

Magnesium Base Alloys, Copper Base Alloys
• Major Elements and Minor Elemental Constituents – XRF
• Trace Elements – Graphite Furnace Atomic Absorption

MECHANICAL

METALLOGRAPHY AND MICROHARDNESS (Metallic Materials)

Microexamination: Surface Conditions
• Alloy Depletion
• Oxidation / Corrosion Layers
• Casting Surface Reactions (Mold Reactions)
• Diffusion Coatings (Carburizing, Nitriding)
• Intergranular Attack / Intergranular Oxidation (IGA/IGO)
• Alpha Case on Titanium Alloys (Cast/Wrought/Thermal Processes)

Microhardness
• Anoop
• Vickers

(Applied loads of less than 1 kgf performed on mounted and metallographically polished specimens)

HARDNESS

DIFFERENTIAL THERMAL ANALYSIS

• Differential Thermal Analysis

Low Stress Grinding & Polishing

Residual Stress: X-Ray Diffraction