Precipitate transformation from NiAl-type to Ni2AlMn-type and its influence on the mechanical properties of high-strength steels

Abstract The precipitate transformation from NiAl-type to Ni 2 AlMn-type and its influence on the mechanical properties of the Fe–5Ni–1Al− x Mn ( x  = 0, 1, 3, and 5 wt.%) alloys were studied thoroughly through a combination of three-dimensional atom probe tomography (APT), first-principles calculations and mechanical tests. APT reveals the precipitation of NiAl-type nanoparticles in the 0-3Mn alloys and the co-precipitation of fine NiAl-type and coarse Ni 2 AlMn-type nanoparticles in the 5Mn alloy, in which the Ni 2 AlMn-type nanoparticles are formed as a result of the coarsening of the NiAl-type ones. The first-principles calculations indicate that the Ni 2 AlMn-type nanoparticles are energetically more favorable than the NiAl-type ones, but their nucleation and growth kinetics are relatively slow, resulting in the initial precipitation of the NiAl-type nanoparticles and the later precipitate transformation from NiAl-type to Ni 2 AlMn-type. A quantitative analysis of the strengthening mechanism reveals that although the Ni 2 AlMn-type nanoparticles have a higher strengthening efficiency than the NiAl-type ones, they make a minor contribution to the total strengthening effects due mainly to their small number density. In addition, the Ni 2 AlMn-type nanoparticles with a composition consistent with that of the Heusler phase are likely to promote the brittle cleavage and intergranular fracture of the 5Mn alloy, resulting in a significant decrease of the alloy ductility.

[1]  David C. Dunand,et al.  Creep properties and microstructure of a precipitation-strengthened ferritic Fe–Al–Ni–Cr alloy , 2014 .

[2]  R. Taillard,et al.  The precipitation of the intermetallic compound NiAl in Fe-19wt.%Cr alloys , 1982 .

[3]  Risto M. Nieminen,et al.  Structural properties of magnetic Heusler alloys , 1999 .

[4]  A. Sutton,et al.  The bcc-to-9R martensitic transformation of Cu precipitates and the relaxation process of elastic strains in an Fe-Cu alloy , 2000 .

[5]  D. Isheim,et al.  Effects of increased alloying element content on NiAl-type precipitate formation, loading rate sensitivity, and ductility of Cu- and NiAl-precipitation-strengthened ferritic steels , 2016 .

[6]  L. Brown,et al.  A dispersion strengthening model based on differing elastic moduli applied to the iron-copper system , 1972 .

[7]  D. Seidman,et al.  The temporal evolution of the decomposition of a concentrated multicomponent Fe-Cu-based steel , 2008 .

[8]  D. Isheim,et al.  Aging characteristics and mechanical properties of 1600 MPa body-centered cubic Cu and B2-NiAl precipitation-strengthened ferritic steel , 2014 .

[9]  D. F. Stein,et al.  A dislocation dynamics approach to prediction of cleavage planes in b.c.c. metals , 1971 .

[10]  E. Kozeschnik,et al.  Simulation of Precipitation Kinetics and Precipitation Strengthening of B2-precipitates in Martensitic PH 13–8 Mo Steel , 2012 .

[11]  D. Ponge,et al.  Nanoprecipitate-hardened 1.5 GPa steels with unexpected high ductility , 2009 .

[12]  S. R. Goodman,et al.  An FIM-atom probe study of the precipitation of copper from lron-1.4 at. pct copper. Part II: Atom probe analyses , 1973 .

[13]  M. Doi.  Elasticity effects on the microstructure of alloys containing coherent precipitates , 1996 .

[14]  David N. Seidman,et al.  Nanoscale co-precipitation and mechanical properties of a high-strength low-carbon steel , 2011 .

[15]  Wang,et al.  Correlation hole of the spin-polarized electron gas, with exact small-wave-vector and high-density scaling. , 1991, Physical review. B, Condensed matter.

[16]  Michael K Miller,et al.  High-strength steels hardened mainly by nanoscale NiAl precipitates , 2014 .

[17]  D. Ponge,et al.  Designing Heusler nanoprecipitates by elastic misfit stabilization in Fe–Mn maraging steels , 2014 .

[18]  A. Hirata,et al.  Microstructure characterization of Cu-rich nanoprecipitates in a Fe–2.5 Cu–1.5 Mn–4.0 Ni–1.0 Al multicomponent ferritic alloy , 2013 .

[19]  V. Radmilović,et al.  A hierarchical microstructure due to chemical ordering in the bcc lattice: Early stages of formation in a ferritic Fe–Al–Cr–Ni–Ti alloy , 2015 .

[20]  K. Furuya,et al.  Discontinuous coarsening behavior of Ni(2)MnAl intermetallic compound during isothermal aging treatment of Fe-Mn-Ni-Al alloys. , 2010, Journal of electron microscopy.

[21]  S. R. Goodman,et al.  An FIM-atom probe study of the precipitation of copper from lron-1.4 at. pct copper. Part I: Field-ion microscopy , 1973 .

[22]  G. Smith,et al.  High-resolution electron microscopy studies of the structure of Cu precipitates in α-Fe , 1994 .

[23]  A. Argon,et al.  Strengthening Mechanisms in Crystal Plasticity , 2007 .

[24]  Dieter Isheim,et al.  Analysis of Three-dimensional Atom-probe Data by the Proximity Histogram , 2000, Microscopy and Microanalysis.

[25]  M. K. Miller,et al.  Atom-Probe Tomography: The Local Electrode Atom Probe , 2014 .

[26]  Michael K Miller,et al.  Effects of Mn partitioning on nanoscale precipitation and mechanical properties of ferritic steels strengthened by NiAl nanoparticles , 2015 .

[27]  G. Rayner,et al.  Accelerated precipitation in the AFA stainless steel Fe–20Cr–30Ni–2Nb–5Al via cold working , 2014 .

[28]  M. Jenkins,et al.  Structural changes of 9R copper precipitates in an aged Fe-Cu alloy , 2000 .

[29]  D. Vanderbilt,et al.  Soft self-consistent pseudopotentials in a generalized eigenvalue formalism. , 1990, Physical review. B, Condensed matter.

[30]  C. Liu,et al.  Precipitation mechanism and mechanical properties of an ultra-high strength steel hardened by nanoscale NiAl and Cu particles , 2015 .

[31]  C. Liu,et al.  Microstructures and mechanical properties of NiAl–Ni_2AlHf alloys , 1990 .

[32]  T. Gladman,et al.  Precipitation hardening in metals , 1999 .

[33]  M. Mills,et al.  Creep response and deformation processes in nanocluster-strengthened ferritic steels , 2008 .

[34]  Po-Yu Chen,et al.  Interphase precipitation of nanometer-sized carbides in a titanium–molybdenum-bearing low-carbon steel , 2011 .

[35]  D. Isheim,et al.  A New Paradigm for Designing High-Fracture-Energy Steels , 2010 .

[36]  G. Smith,et al.  Transmission electron microscope investigations of the structure of copper precipitates in thermally-aged Fe—Cu and Fe—Cu—Ni , 1991 .

[37]  C. J. Smithells,et al.  Smithells metals reference book , 1949 .

[38]  C. Liu,et al.  Ordered intermetallic alloys, part I: Nickel and iron aluminides , 1993 .

[39]  Hong Wu,et al.  The microstructure of near-equiatomic B2/f.c.c. FeNiMnAl alloys , 2011 .

[40]  Yanfei Gao,et al.  Deformation mechanisms in a precipitation-strengthened ferritic superalloy revealed by in situ neutron diffraction studies at elevated temperatures , 2015 .

[41]  R. A. Johnson,et al.  Analytic embedded atom method model for bcc metals , 1989 .

[42]  Mark Asta,et al.  New design aspects of creep-resistant NiAl-strengthened ferritic alloys , 2013 .

[43]  C. Liu,et al.  Synergistic effects of Cu and Ni on nanoscale precipitation and mechanical properties of high-strength steels , 2013 .

[44]  A. Hirata,et al.  A nanoscale co-precipitation approach for property enhancement of Fe-base alloys , 2013, Scientific Reports.

[45]  D. Seidman,et al.  Interfacial segregation at Cu-rich precipitates in a high-strength low-carbon steel studied on a sub-nanometer scale , 2006 .

[46]  A. Kelly,et al.  Strengthening methods in crystals , 1971 .

[47]  K. F. Russell,et al.  Strategies for fabricating atom probe specimens with a dual beam FIB. , 2005, Ultramicroscopy.

[48]  I. Baker,et al.  Evolution of the microstructure and mechanical properties of eutectic Fe30Ni20Mn35Al15 , 2011 .

[49]  H. Lee,et al.  Precipitation and fracture behaviour of Fe–Mn–Ni–Al alloys , 2013 .