ISSN:
1432-0630
Keywords:
66.30.Jt
;
61.70.Tm
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Abstract The time evolution of the aluminium concentration profiles in ion-implanted nickel-aluminium alloys during annealing has been studied in the temperature range 550–800°C using the (p, γ) resonance broadening method. The surface enrichment of aluminium has been found to be balanced by a corresponding uniform decrease in the bulk concentration and hence the bulk concentration profiles can be described by the modified solution of the second diffusion equation, when the implanted concentration does not exceed the solubility limit. When the solubility limit is exceeded the time evolution follows the solubility controlled flow of the solutes. The dependence of the degree of surface enrichment on the extra irradiation of58Ni+ before and after the aluminium implantation is demonstrated and is found to be significant only in the post-irradiation cases. This is taken as evidence of the importance of interstitials in the development of the bulk concentration profiles. The linear Arrhenius plot extracted from the measurements indicates that the diffusion of A 1 in Ni can be described by the activation energyE=2.69 eV and the pre-exponential factorD 0=0.6 cm2/s. Solid solubilities of aluminium in nickel from the implanted distribution are found to agree with those obtained using conventional metallographical methods.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00903214
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