The hardness of a material (mostly aluminium components) is defined as its resistance to the penetration of a (harder) body. This relatively general definition allows very different processes and principles. The hardness values determined with different methods are therefore not comparable or only comparable subject to reservations. If hardness test results are to be compared, this is only possible without comparative measurement for the same test method with the same test parameters (load type, type of measurement, measured variable, indenter geometry, indenter material, magnitude of load).
By definition, stationary (classical) macro hardness testing according to Vickers, Rockwell and Brinell can only be used for elastic-plastic or elastic-viscoplastic materials. In these materials, the yield strength Rp is smaller than the tensile strength Rm, which leads to irreversible deformations. In addition to the methods conforming to the above standards (e.g. TIV), various principles are used for elastic-plastic materials and only elastic (rubber-like) materials (e.g. Shore).
The test according to Brinell (DIN EN ISO 6506-1, is carried out with a ball diameter of 1mm, 2.5mm and 5mm), Vickers (DIN EN ISO 6507-1) and Rockwell (DIN EN ISO 6508-1).
A fast and uncomplicated execution makes short-term results possible.
Magnetic particle testing is used for the detection of surface defects in ferromagnetic materials (mainly steel) and offers the highest sensitivity for the detection of surface cracks.
A magnetic field is introduced into the test object by means of various magnetization techniques. Close to and in the surface of the test object, where the magnetic properties (relative permeability) of the material change significantly (e.g. cracks), the magnetic field emerges from the surface as magnetic flux leakage.
This magnetic flux leakage can be visualized by coloured (usually black or fluorescent) magnetisable particles (magnetic powder) applied to the test object during the test.
With magnetic particle inspection, only defects close to the surface can be detected up to a maximum depth of approx. 2 mm (standard value) below the surface. In the case of wide open or flat surface irregularities, procedural limitations exist with regard to the detectability of these displays under UV light. These can only be reliably detected by means of a visual inspection (VT) under appropriate VT light conditions (no UV light). Furthermore, it is generally not possible to determine a defect depth within the framework of a magnetic particle inspection (MT) or a visual inspection (VT).
Compared to other non-destructive testing methods, magnetic particle testing can also be used for complicated material geometry and unmachined surfaces.
Thermography is a method of non-contact detection and evaluation of thermal radiation invisible to the human eye, the so-called infrared radiation, of an object or body. Thermography is used in research, manufacturing, production preparation, acceptance and preventive maintenance.
The component is irradiated with infrared rays and thus the internal thermal conductivity properties of the component can be made visible. The infrared image changes due to inhomogeneities or cracks and the defect can be seen on the thermographic image.
Passive thermography enables the acquisition, comparison and measurement of an actual thermal condition without additional excitation sources. It covers the areas of machine diagnostics, electrical thermography, building thermography and plant thermography.
In active thermography, a heat flow is excited in the test object. This makes defects in the component visible.
Thermography is a non-contact, imaging and therefore very fast NDT method with which even complex geometries can be inspected with little effort.
During the visual inspection, the surface of the component to be inspected is examined for deviations under strict conditions with regard to the lighting conditions and the capabilities of the inspector.
During the test, the component is examined for deviations on the component surface. The inspector can use optical aids such as magnifiers, microscopes and endoscopes to examine the surface of the component for deviations in shape, imperfections and the surface condition of a product. Visual inspection can only be used to detect displays running along the surface.
In addition, it is generally not possible to determine a defect depth within the framework of a visual inspection (VT).
The visual inspection is an important supplementary inspection, since only with this inspection procedure can the grossest procedural errors be brought to light and the customer's process can be changed over promptly. We are also happy to offer you fully automatic visual inspection.
The radiographic examination shows us the interior of the component and the areas in which there are indications such as air and material inclusions. For this purpose, the components are positioned in a fully protective X-ray system and irradiated with electrically generated X-rays. The so-called live image is transmitted via a detector to a monitor, which is used by a trained X-ray inspector for evaluation. The evaluation of an X-ray image can also be automated.
By means of our modern X-ray systems, we are able to detect displays in your components from 0.2 mm in any desired direction. This display recognition depends on the wall thickness and the material.