| Title |
Depth-Dependent Hardness Characterization by Nanoindentation using a Berkovich Indenter with a Rounded Tip |
| Authors |
김주영(Ju Young Kim); 김민철(Min Chul Kim); 이윤희(Yun Hee Lee); 김재현(Jae Hyun Kim); 권동일(Dong Il Kwon) |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
Indentation size effect; Nanoindentation; Rounded tip effect |
| Abstract |
The height difference △hb between the ideally sharp Berkovich indenter tip and a rounded tip was measured by direct observation using atomic force microscopy (AFM). The accuracy of the indirect area function method for measuring △hb was confirmed. The indentation size effects (ISE) in (100) single crystal copper, (100) single crystal tungsten, and fused quartz were characterized by applying the ISE model considering the rounded tip effect. The model fit the data well for these materials even though fused quartz does not deform by dislocations. However, a very small value of the ISE characteristic length h` was obtained for fused quartz. The present h` value for (100) copper is 32% larger than a previously-measured value for polycrystalline copper. This may indicate that grain boundaries suppress the dislocation activity envisioned in the ISE model. |