Dynamic Fracture Toughness Measurement.
Abstract
An improved crack velocity monitoring procedure able to cope with irregular crack initiation and crack acceleration in ceramics has been developed and used to obtain KId measurements for silicon nitride, polycrystalline alumina and magnesia. The system allowed extended recording times at fast sweep rates for open-camera single shot oscilloscope work. Velocity data was obtained for three point bend tests on PMMA using surface resistance grids to monitor crack growth and an auto-resistance technique was used for velocity measurements during bend tests on tool steels. For the latter, the data was interpreted using an iterative procedure based on an empirical estimate of the functional dependence of the dynamic potential output. Consistent and reproducible data was obtained using auto-resistive crack length measurements for fast fracture in bending, tension and combined impact-tension tests but the interpretation of the resulting data requires further clarification.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1975
- Accession Number
- ADA016933
Entities
People
- B. K. Denton
- J. Congleton
Organizations
- Newcastle University