Synthesis and characterization of hardened Cu-Fe-Ni-P alloy

In the manufacturing industry of electrical contacts, the prohibition of the use of toxic metals (Cd, Be), and desire to avoid the alloying with precious metals (Ag) has created a need for new alloys with good electrical conductivity and high mechanical properties at elevated temperatures. As a potentially useful material for this purpose, we have analyzed the continuously cast Cu-Fe-Ni-P alloy in various heat treatment conditions. Sequence of phase transformations during heat treatment was followed by 4 point D.C. electrical resistivity measuring method, and analyzed by scanning (SEM) and transmission (TEM) electron microscopy. Measurements of Vickers hardness and electrical conductivity after various heat treatment procedures indicate on high potential of Cu-Fe-Ni-P alloys as a material for electrical contacts

High dose ion irradiation effects on immiscible AlN/TiN nano-scaled multilayers

The effects of high dose Ar ion irradiation on immiscible AlN/TiN multilayered structures were studied. The structures with 30 alternate layers of a total thickness of ~ 260 nm were deposited by reactive sputtering on (100) Si wafers. Individual layer thickness was ~ 8 nm AlN and ~ 9.3 nm TiN. Irradiation was done with 180 keV Ar ions to 1 × 10-8 × 10 ions/cm, with the projected range around mid-depth of the structures. It was found that the highest applied dose induced a considerable intermixing, where the growing TiN grains consume the adjacent AlN layers, transforming partly to (TiAl)N phase. Intermixing occurs due to a high contribution of collision cascades, which was not compensated in demixing by chemical driving forces. However, a multilayered structure with relatively flat surface and interfaces is still preserved, with measured nano-hardness value above the level for the as-deposited sample. The results are compared to other systems and discussed in the light of the existing ion beam mixing models. They can be interesting towards better understanding of the processes involved and to development of radiation tolerant coatings. © 2012 Elsevier B.V. All rights reserved