Abstract
Molybdenum-rhenium alloys containing 40 to 48% Re by weight are commonly used for many high-technology applications. Higher rhenium contents bring the alloys into a two-phase region with the presence of brittle o-phase, an intermetallic compound with the approximate composition of Mo 2Re3. Alloys with lower rhenium contents do not possess sufficient low-temperature ductility and high-temperature strength. Available phase diagrams for the molybdenum-rhenium system contain conflicting information about the single-phase/two-phase borderlines. Further, the formation of σ-phase and its influence on mechanical properties depends on forming process and heat treatment, diffusion rate, precipitation mechanism, and morphology. Very few data on these factors are available in the literature. Three alloys were selected for study of the formation of o-phase: Mo-41Re, Mo-44.5Re, and Mo-47.5Re. Applying different production parameters, especially heat treatments, the properties of the alloys were evaluated using microstructure examinations, electron probe microanalysis, and hardness testing. It was found that any harmful influence of o-phase can be largely eliminated by properly adjusting and controlling the processing parameters. Modification of the chemical composition allows the presence of o-phase to be avoided with no deterioration of low-temperature properties.
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B.D. Bryskin and F.C. Danek, Powder Processing and the Fabrication of Rhenium,JOM, Vol 43 (No. 7), 1991, p 24–26
B.D. Bryskin, Rhenium and Its Alloys,Adv. Mater. Process., Vol 142 (No. 3), 1992, p 22–27
J.-C. Carlen and B.D. Bryskin,“Rhenium—A Unique Rare Met- al,” presented at 122nd TMS Annual Meeting (Denver), 21–25 Feb, 1993
E.M. Savitskii, M.A. Tylkina, and K.B. Povarova, Rhenium Alloys,Izd. Nauk Moskva, 1965 (Israel Program for Scientific Translations, Jerusalem, 1970, p 135–142)
R.I. Jaffee, C.T. Sims, and J.J. Harwood, The Effect of Rhenium on the Fabricability and Ductility of Molybdenum and Tungsten,3rd Plansee Seminar Proc, Plansee Meta AG, Tirlo, Austria, 1958, p 380–411
D.J. Maykuth, F.C. Holden, and R.I. Jaffee, The Workability and Mechanical Properties of Tungsten-Molybdenum-Base Alloys Containing Rhenium,Electrochemical Society: Symposium on Rhenium, Elsevier, 1962, p 114–125
J.A. Shields, Jr., The Effect of Annealing Practice on the Structure and Mechanical Properties of P/M Mo-47.5%Re Alloy,Adv. Powder Metall. Partie. Mater., Vol 8, 1992, p 199–211
P. Falbriard, P. Rochette, and G. Nicolas, Refractory Materials Likely to Be Used in the Net Divertor Armour,Refract. Met. Hard Mater., Vol 10, 1991, p 37–43
B.D. Bryskin and D.J. Diaz, Metallography and Characterization of Rhenium and Rhenium Bearing Alloys,Adv. Powder Metall. Panic. Mater, Vol 8, 1992, p 183–197
J.A. Kish, Rhenium and Rhenium-Bearing Alloys,Metals Hand- book, 9th ed., Vol 9,Metallography and Microstructures, Ameri- can Society for Metals, 1985, p 447-448
B.D. Bryskin and J.-C. Carlen, unpublished data
G.A. Geach and J.E. Hughes, The Alloys of Rhenium with Molybdenum or with Tungsten and Having Good High-Temperature Properties,2nd Plansee Seminar Proc, Plansee Meta AG, Tirlo, Austria, 1958, 1955, p 245–253
R. Eck, Molybdenum-Rhenium Alloys as Weldable High Temperature Construction Materials,Int. J. Refract. Hard Met., Vol 5 (No. 1), 1986
A.J. Bryhan, Joining of Molybdenum Base Metals and Factors Which Influence Ductility,Weld. Res. Counc. Bull., Vol 312, Feb 1986, p 12–21
J. Wadsworth, T.G. Nieh, and J.J. Stephens, Recent Advances in Aerospace Refractory Metal Alloys,Int. Met. Rev., Vol 33 (No. 3), 1988,p 131–150
”High Temperature Materials Program,” Progress Report No. 39, Part A, GE-NMPO, GEMP-39A, 30 Sept, General Electric, 1964, p 42–44
D. McLean,Grain Boundaries in Metals, Monographs on the Physics and Chemistry of Materials, Oxford, 1957, p 34–106
S.Q. Xiao and P. Haasen, HREM Investigation of Homogeneous Decomposition in a Ni-12 at % Al Alloy,Ada Metall. Mater, Vol 39 (No. 4), 1991, p 651–659
M.-L. Jungfleish and J.J. Farby, Powder Metallurgy of Refractory Alloys Containing Rhenium,Electrochemical Society Symposium on Rhenium, Elsevier, 1962, p 111–113
J. A. Shields, Jr., Molybdenum and Its Alloys,Adv. Mater. Process., Vol 142 (No. 4), 1992, p 28–36
C.T. Sims and R.I. Jaffee,“Properties of Refractory Alloys Containing Rhenium,” ASM Reprint No. 164, 1959,p 1–14
F. Morito, Microstructures and Mechanical Behavior of Mo-Re Welds,13th Plansee Seminar Proc, Vol 1, Plansee Meta AG, Tirlo, Austria, 1958, 1993, p 585–598
CM. Sonsino and G. Schlieper, Improvement of Mechanical Properties of Diffusion- and Prealloyed Sintered Steels by Heat Treatments,Powder Metall. Int., Vol 6, Nov 1992, p 339–345
J.E. Peters, Recent Developments in Rhenium and Rhenium Alloy Powder Metallurgy,J. Met., April 1969
J.-C. Carlen,“Molybdenum-Rhenium Alloy,” Patent Application, Serial No. 08/010,389, 28 Jan, 1993
Micron Inc.,“Molybdenum/Rhenium Alloy,” Report 17739, 11 May, 1993
V.I. Trefilov and Yu.V. Milman, Physical Basis of Thermomechanical Treatment of Refractory Metals,12th Plansee Seminar Proc, Vol 1, Plansee Meta AG, Tirlo, Austria, 1958, 1989,p 107–131
J.-C. Carlen and B.D. Bryskin, Cold Forming Mechanisms and Work Hardening Rate for Rhenium,13th Plansee Seminar Proc, Vol 1, Plansee Meta AG, Tirlo, Austria, 1958, 1993, p 79–92
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Carlen, J.C., Bryskin, B.D. Concerning Sigma-Phase in Molybdenum-Rhenium Alloys. JMEP 3, 282–291 (1994). https://doi.org/10.1007/BF02645854
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DOI: https://doi.org/10.1007/BF02645854