The evolution of microstructure in Cu–8.0Ni–1.8Si–0.15Mg alloy during aging

Improvement in strength and thermal conductivity of powder metallurgy produced Cu–Ni–Si–Cr alloy by adjusting Ni/Si weight ratio and hot forging

“…In a further comparison of the mechanical properties with the earlier work (Cu-8Ni-1.8Si alloy cast) [27], although our P/M alloy has lower Ni and Si contents, by adjusting Ni/Si ratio and hot forging, the average microhardness and yield strength obtained from our work are higher than those of the earlier work [27]. However, the tensile strength of our P/M alloy is lower than that of the earlier work [27].…”

“…However, up to now, the microstructure of the precipitation for the Cu-Ni-Si alloys with high Ni contents or high Ni/Si ratio has not been studied systematically. Only few articles [5,7,15,27] have been published to determine the microstructure of the precipitation for the Cu-Ni-Si alloys with high Ni contents (>6.0 wt.%). In this study, to provide an optimal balance of mechanical properties, reasonable thermal conductivity and fine grain, the composition of the P/M alloys designed essentially consists of a higher wt.% Ni (7.0 wt.%) and a higher Ni/Si ratio (around 4), with a third alloy element, Cr, added.…”

Phase transformations behavior in a Cu–8.0Ni–1.8Si alloy

“…The ␦-Ni 2 Si structure was found by Toman [20] to have structural parameters of a = 0.703 nm, b = 0.499 nm and c = 0.372 nm. The ␤-Ni 3 Si structure was a simple cubic lattice with a = 3.51 nm [21][22][23]. From the analysis in Fig.…”

“…After solution treatment, followed by different conditions of isothermal treatment and aging process, DO 22 ordering, discontinuous precipitation (cellular structure) and continuous precipitation (␦-Ni 2 Si) occurred in the alloy.…”

Modulated (Spinodal) Alloys

“…A large number of investigators studied on Cu-Ni-Fe [4-5, 6, 7-11], Cu-Ni-Sn [3,4,12,[13][14][15][16][17], Cu-Ni-Cr [18-19, 21,22, 23-25, 10, 26-28] and Cu based other alloys [29][30][31] using X-ray diffraction, transmission electron microscopy, electron diffraction, resistivity measurements and other techniques for example magnetic analysis and neutron diffraction.…”