Investigation of the Impact Performance of Various Glass and Ceramic Systems.
Abstract
This report describes a study of the strength impact and fracture behaviour of a range of ceramic materials. One part of the research is concerned with ceramics which have applications as radomes or infra-red transmitting window materials, the other with ceramics with potential application in body armour. Ceramics included in the study include zinc sulphide, various glass ceramics and aluminas, silicon carbide, silicon nitride, titanium diboride and boron carbide. in one series of experiments we have measured post-impact (i.e. residual) strength curves. These experiments involve impacting specimens at chosen velocities and then measuring the residual strengths after impact. Strength is plotted as a function of velocity. Such curves give: (i) the threshold velocity above which strength degradation following impact occurs; (ii) the fall in strength above the threshold; (iii) a ready comparison with other materials or between different batches of the same material which have had, for example, different surface preparations. From these strength curves, it is.....possible to estimate the size of the flaws which control the damage. Microscopy studies of the fracture faces have been made to locate the nucleating flaws so that there is a crosscheck with the flaw sizes calculated. In cases where physical property data were not available, they were measured. Tables give data on hardness, fracture toughness, elastic moduli, stress wave and fracture velocities. (Keywords: Fracture, Impact, High-speed Photography, Hardness, Strength, Ceramics, Glasses.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 27, 1987
- Accession Number
- ADA178115
Entities
People
- D. Townsend
- John Edwin Field
Organizations
- University of Cambridge