Tailoring the mechanical properties of sputter deposited nanotwinned nickel-molybdenum-tungsten films

Anomalous texture development induced by grain yielding anisotropy in Ni and Ni-Mo alloys

“…Alloying of the Ni films with a low amount of Mo is reported to have a minor effect on the elastic constants of the alloy [52,53], and therefore the predicted texture map above (Fig. 10) should also be applicable to Ni-Mo alloy films with low Mo contents.…”

Fatigue behavior of freestanding nickel–molybdenum–tungsten thin films with high-density planar faults

“…[19][20][21][22][23][24] Nickel (Ni) is one of the most commercialized fcc metals in structural applicationsfrom turbine blades to MEMS devices owing to its resilience against corrosion and creep. 25,26 Strengthening Ni by introducing planar faults has been challenging due to its inherently high SFE, but recently Sim et al 27,28 experimentally demonstrated that alloying Mo and W in Ni produces a microstructure with significant amounts of planar faults. Nickel-molybdenum-tungsten (Ni-Mo-W) films fabricated by sputter deposition displayed an unprecedented tensile strength (∼3 GPa) and microstructural stability.…”

Individual Layer Thickness Dependence of Microstructure and Mechanical Properties of Magnetron Sputtering Mo-W-Doped Ni/Ni3Al Multilayers

“…To overcome these shortcomings of Ni-W thin films, the recent sputtering of Ni-Mo-W ternary films with no more than 6 at.% W additions, showing an extraordinary balance of strength and toughness, underpinned by the formation of the growth of nano-twins [20,21]. Due to this suite of properties, Ni-Mo-W films possess a lower and tailorable coefficient of thermal expansion [22] and are compatible with the wafer-level manufacturability of metal MEMS devices [23].…”

“…This is due to the well-known hydrogenation properties of Ni and the higher hydrogenation capacity of W with respect to Mo [26], which are also used as cathodes for hydrogen production using electrolysis from water [27]. However, Mo atoms exhibit weaker inhibition on grain growth compared with W atoms; the enhancement of the microstructure stability and hardness for Mo-W-doped Ni-based film is limited [21]. To further improve the mechanical properties of as-sputtered nanocrystalline thin films, the combination of the elements doped, and the nanoscale multilayer architecture can provide the strategy to achieve [28][29][30][31][32][33][34].…”