Abstract
A microscratch technique for determining the fracture toughness of brittle intermetallics is presented. Advantages include very small sample sizes and multiple tests on a single, flat polished surface. The fracture toughnesses of single-crystal NiAl in {001}〈100〉, {001}〈110〉, {110}〈110〉, and {110}〈100〉 crack orientations were evaluated using this technique. The results of the scratch testing are compared with measurements on small compact tension samples. Also, transmission electron microscopy is used to help explain the dislocation character of the resulting plastic zones in samples tested. Lastly, a model for determining the dislocation velocity during nanoindentation is presented to help understand the ductile-brittle transition temperature of semibrittle materials.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 301-308 |
| Number of pages | 8 |
| Journal | Materials Science and Engineering A |
| Volume | 192-193 |
| Issue number | PART 1 |
| DOIs | |
| State | Published - Feb 15 1995 |
Bibliographical note
Funding Information:The authors are grateful for support from the Department of Energy, Basic Sciences Division. Grant DE-FG07-84ER45141 (WWG, JWH, and HH) and the Center for Interfacial Engineering at the University of Minnesota under Grant NSF/CDR-872 155 1 (SKV). Furthermore, we would like to thank Drs. Ram Darolia, General Electric Aircraft Engines, and Joachim Schneibel, Oak Ridge National Laboratory, for providing the single-crystal NiAl and polycrystalline A&SC materials used.
Keywords
- Aluminium
- Nickel
- Toughness