Properties and Application of Two-Phase Intermetallic Alloys Composed of Geometrically Close Packed Ni3X(X:Al and V) Structures

2008 ◽  
Author(s):  
Takayuki Takasugi ◽  
Yasuyuki Kaneno
Keyword(s):  
Intermetallic Alloys ◽  
Two Phase ◽  
Phase Intermetallic

Microstructure Analysis of The Channel Regions in Dual Two-phase Intermetallic Alloy Based on The Ni3Al-Ni3V Pseudo-binary Alloy System

2011 ◽  
Vol 1295 ◽  
Author(s):  
T. Moronaga ◽  
Y. Kaneno ◽  
H. Tsuda ◽  
T. Takasugi
Keyword(s):  
High Temperature ◽  
Binary Alloy ◽  
Lattice Misfit ◽  
Alloy System ◽  
Dark Field ◽  
Intermetallic Alloys ◽  
Two Phase ◽  
Transmission Electron ◽  
Phase Intermetallic ◽  
Binary Alloy System

ABSTRACTDual two-phase intermetallic alloys based on the Ni3Al-Ni3V pseudo-binary alloy system have been reported to display high phase and microstructure stabilities and good mechanical properties at high temperature and are therefore considered to be used as a next generation type of high temperature structural materials. The microstructure of the dual two-phase intermetallic alloys is composed of primary Ni3Al and the channel (eutectoid) regions consisting of Ni3Al+Ni3V. In this study, the microstructure of the channel regions was investigated by a transmission electron microscope (TEM). The contrasts of the channel regions showed a complicated microstructure in bright-field images. However, the electron beam diffraction consisted of a single set of patterns and the spots did not accompany streaks, indicating that crystallographic coherency among the constituent phases or the domains is very high. It was also shown that the lattice misfit between the a-axis of Ni3Al and the c-axis of Ni3V is larger than that between the a-axis of Ni3Al and the a-axis of Ni3V. From the dark-field observation, it was found that the c-axis of Ni3V domains in the channel regions is oriented perpendicular to the interface between primary Ni3Al and Ni3V. Therefore, it is suggested that the crystallographic orientation of Ni3V in the channel regions is aligned in the manner of lowering an internal stress caused by the lattice misfit between primary Ni3Al precipitates and Ni3V domains.

Effect of Si Addition on Microstructure and Mechanical Properties of Dual Two-Phase Intermetallic Alloys Based on the Ni3Al-Ni3V Pseudo-Binary Alloy System

2015 ◽  
Vol 1760 ◽  
Author(s):  
Yuki Hamada ◽  
Yasuyuki Kaneno ◽  
Hiroshi Numakura ◽  
Takayuki Takasugi
Keyword(s):  
Mechanical Properties ◽  
Oxidation Resistance ◽  
Base Alloy ◽  
Tensile Elongation ◽  
Alloy System ◽  
Intermetallic Alloys ◽  
Two Phase ◽  
Microstructure And Mechanical Properties ◽  
Phase Intermetallic ◽  
Si Addition

ABSTRACTThe effect of Si addition on microstructure and mechanical properties of dual two-phase intermetallic alloys was investigated. Si was added to the base alloy composition Ni75Al9V13Nb3 + 50 wt. ppm B by three substitution ways in which Si was substituted either for Ni, for Al and for V, respectively. The alloys added with 1 at.% Si showed a dual two-phase microstructure composed of Ni3Al (L12) and Ni3V (D022) phases, while the alloys added with over 2 at.% Si exhibited the same dual two-phase microstructure but contained third phases. The third phases were G phase (Ni16Si7Nb6) and A2 phase (the bcc solid solution consisting of Nb and V). Yield and tensile strength of the 1 at.% Si-added alloys were high in the alloy in which Si was substituted for Al but low in the alloys in which Si was substituted for Ni or for V, in comparison with those of the base alloy. Tensile elongation was lower than that of the base alloy irrespective of substitution ways. The density of the Si added alloys was close to or slightly lower than that of the base alloy. Oxidation resistance of the Si added alloy was increased. Si addition to the dual two-phase intermetallic alloys is beneficial for reducing the density and enhancing the oxidation resistance without a harmful reduction of strength properties.

The Effect of Alloying Elements on Microstructure and Strength Property of Dual Two-Phase Intermetallic Alloys Based on Ni3Al-Ni3V Pseudo-Binary Alloy System

2010 ◽  
Vol 654-656 ◽  
pp. 452-455
Author(s):  
K. Kawahara ◽  
T. Moronaga ◽  
Yasuyuki Kaneno ◽  
A. Kakitsuji ◽  
Takayuki Takasugi
Keyword(s):  
Alloy System ◽  
Interfacial Area ◽  
Intermetallic Alloys ◽  
Two Phase ◽  
Hardness Property ◽  
Phase Intermetallic ◽  
Binary Alloy System ◽  
Ti Addition ◽  
Solute Hardening ◽  
Additional Hardening

The microstructures and hardness property of dual two-phase intermetallic alloys that arecomposed of various kind of volume fractions of geometrically closed packed (GCP) Ni3Al(L12) and Ni3V(D022) phases were studied. The hardness of dual two-phase intermetallic alloys basically was explained by mixture rule in hardness between primary Ni3Al precipitates and eutectoid region.Nb and Ti addition raised the hardness of dual two-phase intermetallic alloys by solid solute hardening in the constituent phases.The additional hardening arising from interfacial area between primary Ni3Al precipitates and eutectoid region was also found. As temperature increases, theadditional hardening decreased for the base and Nb added alloys but decreased little for the Ti added alloys.

Microstructure and Mechanical Properties of Dual Two-Phase Intermetallic Alloys Composed of GCP Ni3Al and Ni3V Phases containing Nb

2006 ◽  
Vol 980 ◽  
Author(s):  
Wataru Soga ◽  
Yasuyuki Kaneno ◽  
Takayuki Takasugi
Keyword(s):  
High Temperature ◽  
Creep Test ◽  
Alloy System ◽  
High Yield ◽  
Intermetallic Alloys ◽  
Two Phase ◽  
Electron Microscopies ◽  
Compression Creep ◽  
Phase Intermetallic ◽  
Multi Phase

AbstractDual multi-phase intermetallic alloys composed of Ni3X (X: Al and V) containing Nb were developed, on the basis of the Ni3Al-Ni3Nb-Ni3V pseudo-ternary alloy system. The dual multi-phase intermetallic alloys were characterized by scanning electron and transmission electron microscopies. High-temperature compression and tension tests, and compression creep test were conducted. It was found that the dual multi-phase intermetallic alloys show high yield and tensile strength with good temperature retention, accompanied with reasonable tensile ductility. The compression creep test conducted at high temperature showed lower creep rate in the dual multi-phase intermetallic alloys than in conventional Ni-base superalloys. The obtained results are superior to the dual multi-phase intermetallic alloys containing Ti.

Alloy design for reducing V content of dual two-phase Ni3Al-Ni3V intermetallic alloys

2012 ◽  
Vol 1516 ◽  
pp. 127-132
Author(s):  
Takahiro Hashimoto ◽  
Yasuyuki Kaneno ◽  
Takayuki Takasugi
Keyword(s):  
Electron Concentration ◽  
Valence Electron ◽  
Base Alloy ◽  
Intermetallic Alloy ◽  
Alloy Design ◽  
Valence Electron Concentration ◽  
Intermetallic Alloys ◽  
Two Phase ◽  
Phase Intermetallic

ABSTRACTThe objective of this study is to establish alloy designing which can reduce the amount of V for a Ni-base dual two-phase intermetallic alloy, without degenerating the dual two-phase microstructure. It was demonstrated that the favorable dual two-phase microstructure will be maintained as far as the valence electron concentration (e/a) of the alloys added by Cr is not so much different from that of the base alloy (i.e. the alloy without additive elements). Consequently, it was found that the dual two-phase microstructure was maintained even though the amounts of V were reduced by 7 at.%, 7 at.%, and 10at.% by substituting of Cr for V, Cr for both of Ni and V, and Cr for Ni, respectively. The hardness of the alloys with reduced V content was higher than that of the base alloy.

Microstructure and Mechanical Properties of Dual Multi-Phase Intermetallic Alloys Composed of Geometrically Close Packed Ni3X Structures

2007 ◽  
Vol 561-565 ◽  
pp. 375-378
Author(s):  
Takayuki Takasugi ◽  
Yasuyuki Kaneno
Keyword(s):  
Mechanical Properties ◽  
Solid Solution ◽  
Tensile Ductility ◽  
High Yield ◽  
Intermetallic Alloys ◽  
Two Phase ◽  
Low Temperature Annealing ◽  
Wide Range ◽  
Phase Intermetallic ◽  
Multi Phase

Dual two-phase intermetallic alloys composed of geometrically close packed (GCP) structures of Ni3Al(L12) and Ni3V(D022) containing Nb were investigated in terms of the microstructural evolution during low temperature annealing (aging) and the related mechanical properties. The eutectoid region, i.e. the prior Al phase (Ni solid solution) is composed of the lamellar-like structure consisting of Ni3Al(L12) and Ni3V(D022) phases. The lamellar-like structure tended to align along <001> direction and on {001} plane in the prior A1 phase (or the L12 phase). In a wide range of temperature, the dual two-phase intermetallic alloys showed high yield and tensile strength, and also reasonable tensile ductility, accompanied with ductile fracture mode.

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