The CORE Microindentation system is a dedicated microindenter that uses capacitive depth measurement and electromagnetic force application to measure the plastic and elastic properties of materials on the micrometer and nanometer scale.
The CORE Microindentation system is ideal for applications that need reliable and accurate hardness and modulus over a wide length scale. It combines a wide force range (30 N) with very high stability and sensitivity not usually associated with a micro hardness tester.
It is fully compliant with the relevant international standards for microindentation - ISO14577 and ASTM E-2546. The broad force range allows one instrument to cover both the Micro (<2 N) and some of the Macro indentation range illustrated in the standards.
The main features of the CORE Microindentation system are as follows:
- Test properties as a function of depth
- Test over a wide load range - maximum load 30 N
- Test “coating-only” properties with ISO compliant techniques
- High stability for longer duration tests such as creep measurements
- Accurate positioning of indentations
- Grid mapping of properties across surfaces
Wide force range
Lower force Micro-indentation curves on polycrystalline tungsten
Microindentation curves on high carbon alloy steel and polycrystalline tungsten though the full force range
Accurate positioning and nanomechanical property mapping
Three axis stage control and integrated digital microscope display allow accurate indentation placement. This can be used for fibre push-out experiments as in the example shown
100 indentations across the surface of cast iron reveal differences in hardness due to graphite lathes
Rapid depth profiling
Rapid multi-cycle load partial unload tests gather data on the depth dependence of elastic modulus and hardness. This is especially useful for examining:
- Multilayer coatings
- Indentation size effects
- Mechanical property gradients in surface engineered graded materials
Hardness profile showing that the indentation size effect in hardness on polycrystalline tungsten persists well into the micro-range.
The CORE software is programmed with ISO compliant data analysis protocols that enable reliable and reproducible measurement of materials. These routines are designed to reduce operator influence on end results.
The common approach of taking the elastic modulus measured at a depth of 1/10 of the coating thickness as the coating modulus can be inaccurate, particularly if coating and substrate have very different elastic properties. ISO 14577(4) recommends an improved approach. The built in analysis software allows extrapolation from low depth modulus data for determining “coating-only modulus” as defined in ISO 14577.