Hardness Enhancement of Sputtered {{Ni}} 3 {{Al}}/{{Ni}} Multilayers
Dokumenttyp:
Zeitschriftenaufsatz
Autor(en):
Tixier, S.; B̈oni, P.; Van Swygenhoven, H.
Abstract:
Ni3Al/Ni multilayers have been grown by magnetron sputtering at room temperature. Structural characterisations were performed by means of X-ray diffraction and re\textasciimacron{}ection. The indentation hardness of the samples as a function of the bilayer thickness has been studied. An increase in hardness up to 88% of the bulk hardness of Ni3Al is observed when bilayer thickness L decreases to Lmax $<$ 100 AÊ . A further decrease in bilayer thickness results in a decrease in hardness. At L . Lmax the hardness variation is found to be compatible with the Hall$\pm$ Petch relation. At L , Lmax, the reduction in hardness is discussed in terms of structure and morphology of the layers. An increase of the mosaic spread of the grains as well as a decrease in density is observed at small L. q 1999 Elsevier Science S.A. All rights reserved.