deposition techniques has been considered to have anisotropy even for amorphous alloys [1]. In this investigation, micro-sized cantilever type specimens were prepared from an electroless deposited Ni-P amorphous alloy thin film and fracture tests for two types of specimens with different crack growth dierctions, which are “in-plane” and “out-of-plane” of the thin film, were performed. Fracture behavior of the specimens is then discussed. EXPERIMENTAL PROCEDURE The material used in this investigation was a Ni-11.5 mass%P amorphous alloy thin film electroless plated on an Al-4.5 mass%Mg alloy. The thickness of the amorphous layer was 12 µm and that of the Al-4.5 mass%Mg alloy substrate was 0.79 mm. A disk with a diameter of 3 mm was cut from the Ni-P/Al-Mg sheet by electro discharge machining. The amorphous layer was separated from the Al-Mg alloy substrate by dissolving the substrate with a NaOH aqueous solution. Two types of micro-sized cantilever beam specimens with different notch orientations were prepared from the amorphous layer by focused ion beam machining, and are referred to as “in-plane type specimen” and “out-of-plane type specimen” as shown in Figs. 1 (a) and (b), respectively. Figures 2(a) and (b) show Figure 1: Two types of specimen orientations. The crack propagation direction is perpendicular to the deposition growth direction for in-plane type specimen (a), while the crack propagation direction is parallel to the deposition growth direction (b). Deposition Direction Loading (a) In-plane type specimen Loading (b) Out-of-plane type specimen Deposition Direction (a) L=30µm Breadth, B: 10µm W=12µm Notch Loading (b) Loading L=30µm W=12µm B=10µm Notch Figure 2: Scanning electron micrographs of micro-sized specimens prepared by focused ion beam (FIB) machining. (a) in-plane type specimen and (b) out-of-plane type specimen. Notches were also introduced by FIB.
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