IIB 2010
在c语言中
Grain boundary engineering:historical perspective and future prospects
Tadao Watanabe
Received:10September 2010/Accepted:12February 2011/Published online:1March 2011ÓSpringer Science+Business Media,LLC 2011
Abstract A brief introduction of the historical background of grain boundary engineering for structural and functional polycrystalline materials is prented herewith.It has been emphasized that the accumulation of fundamental knowl-edge about the structure and properties of grain boundaries and interfaces has been extensively done by many rearchers during the past one century.A new approach in terms of the concept of grain boundary and interface engi-neering is discusd for the design and development of high performance materials with desirable bulk properties.Recent advancements bad on the concepts clearly demonstrate the high potential and general applicability of grain boundary engineering for various kinds of structural and functional materials.Future prospects of the grain boundary and interface engineering have been outlined,hoping that a new dimension will emerge pertaining to the discovery of new materials and the generation of a
new property originating from the prence of grain boundaries and interfaces in advanced polycrystalline materials.
Introduction
During the past century,our knowledge of ,grain boundaries and interpha boundaries in crystalline solids has enormously developed from a tiny ed to a huge tree with many branches.Since 1880s,when Sorby first showed the optical micrographs of a blister steel to
demonstrate the prence of large number of grains with various shapes and sizes and the boundaries between the adjoining grains [1],grain boundaries and interpha boundaries have drawn an increasing attention of materials scientists and engineers who are deeply involved in materials design and development.It has now been well established that the microstructure is cloly related to bulk properties of materials.Accordingly,the control of microstructures has become one of the key issues of the discipline of Physical Metallurgy (earlier)and Materials Science and Engineering (modern).Till date,a large variety of approaches for microstructural control in polycrystalline materials have been attempted by using the available processing methods.The methods include different metallurgical process such as solidification,alloying and thermo-mechani
cal pro-cessing.Much effort has been made to develop a more pow-erful and efficient processing method than the conventional ones.There is always a quest to produce such well engi-neered microstructures that can confer desirable bulk prop-erties,mostly in polycrystalline materials,except the ca of miconductors like silicon which are generally single crystalline,as required by the technological applications.Amongst the past achievements pertaining to the devel-opment of newer processing methods,rapid-solidification,directional solidification,and zone-melting have been developed in the ca of solidification processing.The techniques as well as some other recently developed ones are widely utilized as powerful processing methods of micro-structure control [2–4].In the past three decades,a number of new techniques for materials processing have been devel-oped and some of them have been successfully applied to the production of advanced metallic,miconductor,and cera-mic materials by tailoring desirable and stable microstruc-tures [5].Amongst the the processing methods,processing under magnetic [6,7]and electric fields [8]are noteworthy.
T.Watanabe (&)
Key Laboratory of Anisotropy and Texture of Materials,Northeastern University,Shenyang,China
e-mail:tywata@jp;u.edu T.Watanabe
Tohoku University,Sendai,Japan
J Mater Sci (2011)46:4095–4115DOI 10.1007/s10853-011-5393-z
On the occasion of the iib2010,it may be uful to briefly summarize the previous studies which played important roles in the historical development of interface science,and to re-affirm the established concepts.It is also imperative to mention what needs to be studied further in order to strengthen the new discipline of Interface Engineering for polycrystalline materials with desirable bulk properties and high performance.In the past three decades,the grain boundary and interface engineering has been extensively attempted with basic knowledge of grain boundaries and interfaces,to improve bulk properties and performance of conventional materials.Moreover,grain boundary and interface engineering may have potential to impact a new property and hence,new functions for future advanced materials.The prent author believes that a brief review of important studies of grain boundary-related properties may be uful for the new comers to know the background as well as the recent achievements,and also to specify the milestones leading to the future of Interface Engineering.
As discusd by Swalin almost40years ago[9],the development of science is generally considered to
pass four phas following an S-curve:(i)thefirst‘‘Conceptual pha’’,is the era when nothing is really known about the subject.General philosophical principles,that are involved to explain obrvations,grow very slowly in this pha.(ii) Then comes the‘‘Discovery pha’’,which is a period of rapid acceleration.Discoveries are unexpected and thought provoking.In this pha,numerous but conflicting theories are propod.The rearchfield ems to be full of puzzles. Many highly motivated scientists enter thefield with a hope to achieve notable accomplishments.(iii)The third pha is known as‘‘Breakthrough pha’’.In this pha,the field makes a rapid progress and becomes fashionable in the leading laboratories.The general pattern of scientific events is understood.Thefield is exciting and rewarding. (iv)Ultimately,‘‘Classical pha’’ts in,where the remaining pieces of the jigsaw are put in place.The thought patterns generalized in the breakthrough pha become orthodox and become the conventional wisdom which must be broken through in the next major advance ultimately leveling off until a new breakthrough occurs.In my personal opinion,thefield of grain boundary and interfaces is now passing through the‘‘Breakthrough pha’’experiencing a rapid advancement.Accordingly, the time is ripe for a number of new challenging tasks with adequate theoretical and experimental tools. Development of physical metallurgy to interface science in the twentieth century
Since1880s,when metallographic obrvation of iron and steels wasfirst made by Sorby[1],microstructural aspects have become key to Physical Metallurgy which trans-formed to Materials Science and Engineering(MSE)after 1960s,as reviewed by R.F.Mehl[10]and R.W.Cahn [11].A systematic study of the evolution of microstructure in polycrystalline materials compod of a large variety of grain structures was carefully performed by C.S.Smith in 1940s,tofind the key factors controlling grain growth, paying particular attention to grain boundaries in single pha materials and also inter-pha boundaries in multi-pha alloys[12].Bad on his elaborate effort pertaining to experimental obrvations,it has been revealed that the interface energy plays a key role in the evolution of microstructure in polycrystalline materials.In1950s, probably K.T.Aust and B.Chalmers were amongst thefirst who riously discusd the relation between energy and structure of grain boundaries[13].The structure of grain boundaries wasfirst investigated theoretically by Read and Shockley on the basis of dislocation theory[14,15].On the other hand,optical microscopy of grain boundaries was attempted by Amelinckx through the obrvation of parti-cle decorating boundaries in transparent crystals such as NaCl for low-angle dislocation boundaries[16].Hirsch et al.[17]applied transmission electron microscopy(TEM) for the obrvations of dislocation boundaries in deformed aluminum for thefirst time.
Thefirst book on the topic of the structure and properties of grain boundaries and boundary-related phenomena in polycrystalline materials was written by Donald Mclean in 1957[18].Almost30years later,in1995,Sutton and Balluffipublished their excellent book entitled‘‘Interfaces in Crystalline Materials’’[19].The period between1960s and1980s can be recognized as thefirst half of the breakthrough pha in the history of rearch on grain boundaries and interfaces.During this period,a number of new concepts on grain boundary structure have been pro-pod on the basis of computer simulation and systematic experimental studies with orientation-controlled bicrystal samples,exploring grain boundary structure–property relationship.After1990s,experimental study of the struc-ture–property relationship of grain boundaries have become possible for polycrystalline samples,becau a computer-assisted and fully automated technique for ori-entation determination and boundary characterization Scanning Electron Microscopy bad Electron Back Scat-ter Diffraction(SEM-EBSD)/Orientation-Imaging Micros-copy(OIM)was developed by Adams et al.in the early 1990s[20,21].Subquently,the characterization of grain boundary microstructure by SEM-EBSD/OIM has become a standard method for preci and quantitative analysis of the microstructure in polycrystalline samples of metallic, miconductor,and ceramic materials with different crystal structures and a wide range of grain sizes(from a few 100l m to nanocrystalline range).It is now possible to
characterize samples with grain size down to a few10nm with the u of a Field Emission Gun-Scanning Electron Microscope with orientation imaging microscopy facility (FEG-SEM/OIM)[22].
Table1is a tentative list of important achievements in the rearchfield of grain boundaries and interfaces in crystalline solids during the past almost one century.From this table,one can recognize that the period of1900s–1950s may correspond to‘‘Conceptual Pha’’of scientific development of Interface Science.The next period from 1960s to1980s may correspond to‘‘Discovery Pha’’in which a number of new experimental techniques for the obrvation of structure of grain boundaries and interfaces were developed.The relation between structure and prop-erties of grain boundaries were systematically and carefully studied by using orientation-controlled bicrystals of metals and alloys.In particular,the advent of electron microscopy and its further development to high resolution transmission microscopy(HREM)greatly contributed to experimental verification of the basic concepts of the atomic structures of grain and pha boundaries,both previously stated and newly propod.During this period,the scope of rearch on polycrystalline materials greatly widened from the simplest ca of bicrystal with a single boundary to the extreme ca of nanocrystalline materials which are char-acterized by extremely high volume fraction of grain boundaries,sometimes more than50%of that of the material,as discovered by Gleiter et al.[23].The advent of nanostructured mate
rials opened a new domain in which structure and properties of crystalline interface need to be studied more fundamentally in the light of atomic bonding at crystalline interfaces.The development and usage of a high performance computer greatly enhanced the progress in Interface Science of crystalline solids.
The possibility of a new approach to‘‘Grain Boundary Engineering(GBE)’’,initially called‘‘Grain Boundary Design and Control’’was propod by the prent author in the early1980s[24]to confer desirable bulk properties and high performance to polycrystalline materials.Aust and Palumbo[25]havefirst applied this concept to improve bulk mechanical and fracture properties in structural materials,such as materials for nuclear applications that require high-resistance to stress corrosion cracking.More recently the grain boundary engineering has been applied
Table1A brief history of rearchfield of structure and properties of grain boundaries,interfaces and relatedfields during the past one century
1900s–1940s
如何消灭老鼠Amorphous Cement Theory(Ronhain-Ewen,1912)
Coincidence-Site-Lattice(CSL)Model(G.Friedel1920,Kronberg-Wilson1949)
Transition-Lattice Theory(Hargreaves-Hill,1929)
Geometrical and Topological Approach to GB microstructure(C.S.Smith,1948)
1950s–1960s
Dislocation Theory of Low-angle GBs(Read-Shockley,1952,Amelincks.1957)
Boundary Structure and Properties in Bicrystals(Chalmers-Aust,R.W.Cahn)
Thermodynamics of GBs(J.W.Cahn.1956),First Book on GBs(D.McLean,1957)
Geometrical and Mathematical Approach to CSL(Brandon,Ranganathan.1966)
FIM,TEM Obrvations(Brandon,Ryan-Suiter,Smith,Ralph-Jones,Gleiter)
O-Lattice Theory(Bollmann,1968)
1970s–1980s
HREM of GB Structure(Schober-Balluffi-Bristowe,Sass-Carter,Smith-Pond-King,Ishida-Ichino,Bourret-Bacman,Ru¨hle)
Bicrystal Work in Metals(extensively in France,Russia,Japan)
Extension del to HCP.Non-cubic crystals(Bruggemen-Bishop,Grimmer-Warrington)
Computer Calculations(Biscondi,Vitek-Sutton.Wolf,Doyama-Kohyama)
中山码头Nanocrystalline Materials(Gleiter)心情歌词
Interface in Pha Transformation(Hillert,Aaronson-Enomoto-Purdy,Maki-Furuhara)
1990s–2000s
Microscale Texture Analysis(Lu¨cke-Gottstein,Bunge-Esling)
SEM-EBSD/OIM(Dingley-Adams-Wright-Kunze,1991–1993)
白酒开盖2年后还能喝吗GB Microstructure&Properties in Polycrystalline Materials(Aust-Palumbo-Erb,Ralph-Howell-Jones-Randle,Grabski,
Priester,Watanabe-Kokawa-Tsurekawa)
Bicrystal Berhaviour(Metals:Gottstein-Shvindllerman-Straumal-Molodov-Winning,Paidar-Lejcek,Miura-Hashimoto-Mimaki,
Mori-Monzen-Kato-Miura,Ceramics:Sakuma-Ikuhara-Yoshida-Yamamoto-Shibata)
Triple-Junction Behavior(Gottstein-Shvindlerman,King,Aust-Palumbo)
Nanocrystalline Materials by ECAP Processing(Valiev-Langdon-Nemoto-Horita)
to functional materials.Probably,past1990s,Interface Science and Engineering is passing through the‘‘Break-through pha’’.A number of new experimental techniques are available for the obrvation and characterization of interfacial structure and properties.Theoretical basis has now been reasonably established for complete under-standing of the obrvations pertaining to the structure and properties of crystalline interfaces.However,there is a strong demand for experimental and theoretical basis for future study of statistical and topological features of interfacial microstructure and related properties in single-and multi-pha polycrystalline materials,with the grain sizes ranging over three orders of magnitude from con-ventional micrometer size to nanometer size.A rapid progress in‘‘Interface Science and Engineering’’can be expected,particularly in the area of advanced functional materials such as miconductors and electroceramics where there is a stron
g need for the control of interfaces and also there is a high potential for creation of a new function associated with interfaces,as predicted by Inter-face Engineering.
The origin of the heterogeneity of grain boundary phenomena
As a fundamental understanding,it is a common recogni-tion that grain boundary phenomena can occur very dif-ferently from boundary to boundary in a polycrystalline material.From Fig.1,it is evident that most of the grain boundary phenomena occur very heterogeneously.Some examples are the intergranular fracture in Bi-doped copper (Fig.1a,b)[24],the intergranular corrosion in iron–chro-mium alloy(Fig.1c),and the dynamic grain boundary migration in aluminum under cyclic loading at high tem-perature(Fig.1d)[26].The activity of individual grain boundaries varies greatly amongst themlves,for example,some boundaries tend to break,corrode,and migrate easily,while some others show only a little or no activity.In fact,such heterogeneity and different local behavior of grain boundary phenomena can be appreciated by careful microscopic obrvations in polycrystalline materials.Of cour,we know that the prence of grain boundaries is the primary origin of microstructural differ-ence between a single crystal and a polycrystal.Accord-ingly,the microstructure in polycrystal can greatly vary depending on grain shape,grain size,the dimension of specimen(1D—wire,2D—thinfilm,3D—bulk),and geo-metrical configurations of grain boundaries.
Moreover,there is another important origin of the het-erogeneous occurrence of grain boundary phenomena that is the effect of grain boundary structure and character.In the lastfive decades,much effort has been made to establish the relation between grain boundary structure and properties,particularly by using bicrystal samples of metals and alloys.It is now well established that grain boundary properties strongly depend on the grain boundary structure and character defined at least by the misorientation rela-tionship between adjacent grains:crystallographic orien-tation of the rotation axis,the misorientation angle and the boundary inclination,usingfive geometrical parameters [19].It is our current understanding that the activity of grain boundary phenomena can vary,depending on grain boundary structure and character,as much as one order of magnitude.Furthermore,the grain boundary microstructure which is defined by the grain boundary character distri-bution(GBCD),geometrical configurations of boundaries and other factors[24],can be modified and controlled by the processing method and conditions in polycrystalline materials.Thus,structure-dependent boundary properties are the possible origin of the heterogeneity of grain boundary phenomena decisively controlling bulk properties and performance of polycrystalline materials.Recent studies of grain boundary microstructures in
polycrystalline
Fig.1The heterogeneity of grain boundary phenomena obrved in metallic polycrystalline materials:a,b structure-dependent grain boundary fracture in Bi-doped copper[24].Note that twin boundaries are a strong barrier to the propagation of intergranular crack,c different propensities to intergranular corrosion for the three boundaries meeting at a triple junction in Fe–16%Cr alloy,d struc-ture-dependent dynamic migration during cyclic deformation in aluminum at high temperature[26]小狗作文300字
materials(mostly metallic)have revealed to what extent the processing method and condition can affect the grain boundary microstructures in real engineering materials. Grain Boundary and Interfac
e Engineering has just reached the stage of contributing to the practical applications in order to develop advanced materials with desirable bulk properties and high performance,after the‘‘Breakthrough pha’’,bad on the basic knowledge of structure-depen-dent boundary properties in bicrystals,as shown in the next ction.
Importance of basic knowledge of structure-dependent properties in bicrystals
It was realized since1950s that in order to understand and effectively utilize the influence of grain boundaries on bulk properties in polycrystalline materials,a basic study of the relationship between structure and properties was inevita-bly required[27].A considerable effort has been made toward the study of structure-dependent grain boundary properties by using orientation-controlled bicrystals of metals and alloys,as documented in the classical reviews by Weinberg[28],Goux[29],Gleiter and Chalmers[30], Pande and Chou[31].More recently,systematic and quantitative experimental studies on bicrystals have been performed for refractory metals such as niobium[32], molybdenum[33],non-oxide ceramics[34],oxide ceram-ics[35],and the intermetallics Ni3Al[36].In the past,there were difficulties in the preparation for bicrystals of the materials.However,with the advent of new crystal grow-ing techniques,it is now possible to prepare bicrystals of a variety of materials.In addition to a number of previous studies,the techniques have greatly contributed to the recent progress and est幼儿游泳
经典伴我成长ablishment of the discipline of Materials Interface Science,as reported in the conference proceedings ries,particularly of the iib-conferences [37–39].A more detailed account of the relationship between structure and properties of crystalline interfaces can be obtained from excellent books on this topic[30,40–42].
Figure2a shows the HREM micrographs of the atomic structures of grain boundaries.The misorientation depen-dence of the grain boundary energy for the h110i sym-metric tilt boundaries in zirconia ZrO2bicrystals as experimentally determined by Shibata et al.[43]is pre-nted in Fig.2b.It is evident that the5°low-angle dis-location boundary and low-R(3,9,11)coincidence boundaries posss periodic structures and lower values of the grain boundary energy.On the other hand,high-angle random boundaries without any special misorientation tend to posss higher grain boundary energies.The obrva-tions provide a direct evidence for structure-dependent grain boundary property without any ambiguity.Further-more,the application of Electron Energy Loss Spectros-copy(EELS)and Energy Loss Near Edge Structures (ELNES)with far better energy resolution provide very detailed information on the nature of inter-atomic bonds across grain boundaries in ceramics[43].Such data on structure-dependent boundary properties have been exten-sively accumulated in the past half century and time is
ripe Fig.2a HRTEM images of symmetric tilt grain boundaries in zirconia bicrystals,b the misoreintation dependence of the grain boundary energy (top)and the misorientation dependence of Y gregation at symmetric tilt grain boundaries in Y-stabilized zirconia bicrystals[43]
