M. V.Fedorischeva
,
V.E.Ovcharenko
,
O.B.Perevalova
,
E.V.Kozlov
材料科学技术（英文）
The Ni3B phase was formed when boron (0.5 at. pet B) was added to the intermetallic of stoichiometric and off-stoichiometric (Ni-24 at. pct Al) compounds. In the alloy of stoichiometric composition the particles of Ni3B phase has the size around 0.1 mu m and is located on the grain boundary of the main phase. The decreasing of concentrations of Al in the off-stoichiometric alloy leads to increase in the degree of the long-range order parameter, increasing the concentrations of boron in the solid solution and decreasing its localization on the grain boundary. Microalloying of boron leads to increasing in the fraction of grain monodomains with dislocations up to 0.7 in the alloy of the off-stoichiometric composition and up to 1 in the alloy of the stoichiometric composition. It was established the correlation between the degree of the concentration inhomogeneity, average density of the dislocations and the average long range-order parameter.
关键词:
O.B.Perevalova
,
E.V.Konovalova
,
N.A.Koneva
,
E.V.Kozlov
材料科学技术（英文）
The study of the triple junctions of the grain boundaries in some fcc solid solutions, ordered alloys and intermetallics with L12 has been carried out using the optical metallography and TEM methods. Two-types of the triple junctions were found in the alloys investigated (1), consisting of the boundaries of the random (RT), and (2), consisting of the RT boundary and the special boundaries (ST). The relative values of the RT and ST boundary energy were determined on the basis of the measurements of the angles between the grain boundary planes. It has been shown that the energy of ST boundaries increases with the increase of the stacking fault (SF) energy. The energy of the RT boundaries does not depend on the SF energy.
关键词:
Alloys
,
null
,
null
,
null
I.A.Bozhko
,
S.V.Fortuna
,
I.A.Kurzina
,
I.B.Stepanov
,
E.V.Kozlov
,
Yu.P.Sharkeev
材料科学技术（英文）
The results of experimental study of nanoscale intermetallic formation in surface layer of a metal target at ion implantation are presented. To increase the thickness of the ion implanted surface layer the high intensive ion implantation is used. Compared with the ordinary ion implantation, the high intensive ion implantation allows a much thicker modified surface layer. Pure polycrystalline nickel was chosen as a target. Nickel samples were irradiated with Al ions on the vacuum-arc ion beam and plasma flow source "Raduga-5". It was shown that at the high intensity ion implantation the fine dispersed particles of Ni3Al, NiAl intermetallic compounds and solid solution Al in Ni are formed in the nickel surface layer of 200 nm and thicker. The formation of phases takes place in complete correspondence with the Ni-Al phase diagram.
关键词:
High intensive ion implantation
,
null
,
null
