New impulse for research:

Zwick Vibrophore for Nelson Mandela University in Port Elizabeth (SA)

Vibrophores are used to determine the fatigue strength of materials and components with regard to fatigue and endurance limits. Typical ranges of application are fracture mechanics investigations of CT and SEB specimens, pre-cracking of specimens and fatigue tests on components. The Nelson Mandela University (NMMU) in Port Elizabeth, South Africa, has recently started using a Zwick Vibrophore for its research projects.

The NMMU has close contacts with South African industry and provides support in the form of research work for important development projects. Fatigue tests for the advancement of material quality are vital for the automotive, aerospace and power generation industries.

The NMMU plans to intensify its research in this key area with the aid of Zwick testing technology. The Vibrophore will primarily be used for fracture mechanics investigations on CT and SEB specimens, for pre-cracking specimens and for fatigue tests on components. Operating at resonance frequency, the Vibrophore attains a high force and travel amplitude for a low energy input (only around 2% of the energy consumption of a servo-hydraulic testing machine) by amplifying the oscillating circuit. The high testing frequencies (up to 300Hz) ensure short testing times, allowing greater specimen throughput.

An example of the research group’s contribution to enhanced safety for nuclear-power stations is its investigation of the fatigue limit of graphite (NBG-18) used in the construction of power stations. The fatigue strength of graphite impregnated with radioactivity is tested at various load stages to provide information on its durability.