Experimental Liquidus Surface Projection of the Ni-Ru-Zr System

Hardness characteristics of as-cast Ni-Ru-Zr alloys

“…Selected microstructures are given in Figure 1 to show the different morphologies in the ascast alloys [12]. Table 2 shows the nanohardnesses of the individual intermetallic phases, most of which had composition ranges.…”

“…The carbon coatings needed for SEM analysis [12] were removed by grinding, prior to XRD analyses, to obtain results without carbon. Phase proportions were calculated using the lever rule on the solidification projection for the Ni-Ru-Zr alloys [12]. A CSM® nanoindentor with an atomic force microscope (AFM) was used for nanoindentations on the individual phases.…”

“…Macro-hardness measurements were done on as-cast samples of about 2 g [12] (approximately 10 mm diameter and 7 mm thick) to obtain the hardnesses and identify samples with deleterious brittle phases. A Mitutoyo Hardness tester (Model AVK-CO) was used with a 10kg load, calibrated against a standard aluminium test block according to ASTM E92 [15].…”

“…The Ni-Ru-Zr system had been studied with 21 different as-cast samples using SEM-EDX and identified with XRD, and the as-cast solid ranges and liquidus surface projections were drawn [12]. The samples had been made by arc-melting [12], and their compositions were chosen to derive the phases within the ternary. As well as the extensions of the nine binary phases found, three ternary phases were identified: 1 Zr24Ru22Ni44 (at.%), 2 Zr74Ru4Ni22 (at.%), and 3 Zr35Ru3Ni62 (at.%).…”

“…Solid phases in the as-cast samples of Ni-Ru-Zr [9][10][11]. The prior investigation on the phase diagram of Ni-Ru-Zr [12] gave an opportunity to study these phases, and measure their hardness and phase proportions in 21 samples to help explain the hardness variation of the different alloys, as was done by Hill et al [14], and identify any potential alloys with good mechanical properties. Since there were several phases with different compositions and structures in the Ni-Ru-Zr system, (Table 1) [12], this gave an opportunity to study how hardness was related to crystal structures and compositions, phase proportions and morphology.…”