Structure of the Intermetallic Compound Ni_3Al Synthesized under Compression of the Powder Mixture of Pure Elements Part II: Influence of Alloying by Boron on the phase Composition And the Microstructure of Grains of the Main Phase

摘要

Thi Ni_3B phase was formed when boron (0.5 at. Pct B) was added to the intermetallic of sto- ichiometric and off-stoichiometric (Ni-24 at. Pct Al) compounds. In the alloy of stoichiometric composition the particles of Ni_3B phase has the size around 0.1 μM 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, increasingtheconcen- trations of boron in the solid solution and decreasing its localization on the grain bundary.