Low temperature formation of aluminide layers on nanocrystalline nickel

Formation of aluminide phases on electrodeposited nanocrystalline nickel

“…Therefore, based on XRD and EDS results, the single layer coating formed on MC specimens was composed of Al 3 Ni 2 phase. These observations were consistent with our previous work [14], as well as the results of Tamarin [17], and Goward and Boone [18] who produced the aluminide coating on coarse-grained nickel by high activity aluminizing process and reported the formation of a single layer of Al 3 Ni 2 phase.…”

“…It was also observed that the microstructure of the coating on NC samples aluminized at 500 C and 550 C depended on aluminizing time, that is a coating with single layer and double layers of aluminide phases were formed on NC samples aluminized at short and longtime aluminizing, respectively. The evidences were presented in our previous work (for 500 C) [14] and Fig. 2b of this work (for 550 C).…”

“…SEM and TEM micrographs of MC and electrodeposited NC samples were presented elsewhere [14] and therefore were not shown here. According to them, the average grain size of MC and NC samples were about 30 mm and 27 nm, respectively.…”

“…In our previous work [14], it was indicated that in contrast to the formation a single Al 3 Ni 2 layer on MC nickel in all aluminizing times, the formation of nickel aluminide phases on NC samples depends on aluminizing time such that a single layer of Al 3 Ni 2 and double layers of Al 3 Ni and Al 3 Ni 2 phases formed in short and longtime aluminizing at 500 C, respectively. In this paper, the effect of aluminizing temperature on the formation and growth of the aluminide phases during pack cementation of electrodeposited NC nickel have been investigated and compared with the results of MC samples.…”

“…The SEM micrographs of NC samples aluminized at 500 C have been presented in Ref. [14] and therefore were not shown here. Fig.…”