N.I. Grechanyuk, V.G. Grechanyuk, A. Manulyk
Synergy ANTECH Services Corp.,
Canada
Keywords: rapid evaporation-condensation, copper, molybdenum, vacuum, precipitation-strengthened materials, layered materials, bulk materials
Summary:
The phase composition and structuration of three types of copper and molybdenum composite materials, 0.8 to 5 mm thick, which were condensed from the vapor phase at substrate temperatures 700 0C and 900 0C, are considered: precipitation-strengthened composites, micro-layered composites with alternating copper and molybdenum layers 1 to 10 mm thick, and bulk nanocrystalline composites with alternating layers thinner than 0.5 mm. Standard precipitation-strengthened Cu- and Mo-based materials condensed from the vapor phase at substrate temperatures 700–900 C can be produced over a relatively narrow composition range of the strengthening phase (0.1–3 wt.% Mo). When Mo content is 3–5 wt.%, the molybdenum particles change their shape from round to acicular and become discontinuous chains oriented perpendicularly to the vapor flow. If there is more than 5 wt.% of the second phase, the condensed composite materials (CCMs) show a layered structure. The layered structure can be observed in other CCM types (Cu–W, Cu–Cr, NiCrAlTi– Al2O3). Layered copper and molybdenum CCMs, 6 mm thick, produced on a rotating substrate heated to 700 ± 30 °C have been experimentally confirmed to belong to bulk nanocrystalline materials.