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Definition: A nanoindenter is a measuring system for instrumented indentation testing in the nanometre to micrometre range. The force-displacement curve of an indenter is continuously recorded in order to determine mechanical characteristic values such as nanohardness and elastic modulus. The method is based on evaluation according to Oliver-Pharr.

Practical relevance: Nanoindentation is particularly suitable for thin films, coatings, microstructures or individual microstructural constituents. Typical test loads are in the mN range and indentation depths in the nm range. Hardness (HIT), reduced elastic modulus (Er) as well as creep and relaxation behaviour are assessed. Surface preparation and roughness considerably influence the measurement accuracy.

Decision-making perspectives:

• Technical decision-makers: Characterisation of coatings and graded materials.
• Purchasing/project management: Verification of specified coating properties for high-performance components.
• Science: Investigation of local mechanical properties and microstructural heterogeneity.
• Insurance/law: Documentation of mechanical properties in the event of coating failure.

Typical testing or verification methods: Instrumented indentation testing, force-displacement analysis, evaluation according to ISO 14577.

FAQ:

• What is the advantage of a nanoindenter?
• It enables the determination of local mechanical properties of very small volumes or thin films.

Definition: Non-destructive testing (NDT) comprises testing methods for detecting defects or inhomogeneities in materials and components without damaging them. The aim is to assess integrity during manufacture or operation. Qualification requirements for personnel are governed by DIN EN ISO 9712.

Practical relevance: Typical methods are ultrasonic testing (UT), radiography (RT), magnetic particle testing (MT), penetrant testing (PT) and visual testing (VT). They identify cracks, pores, inclusions or wall thickness losses. NDT is central to pressure equipment, welded structures and safety-relevant plants.

Decision-making perspectives:

• Technical decision-makers: Ensuring component integrity and early defect detection.
• Purchasing/project management: Definition of inspection classes, scopes and documentation requirements.
• Science: Assessment of detection limits and comparison of different testing methods.
• Insurance/law: Evidence of proper testing in the context of safety and liability matters.

Typical testing or verification methods: UT, RT, MT, PT, VT, eddy current testing (ET), wall thickness measurement.

FAQ:

• When is NDT preferable to destructive testing?
• When components have to be tested in their installed state or safety-relevant components have to be assessed without damage.