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Deformation Twinning in Metals and Ordered Intermetallics-Ti and Ti-Aluminides M

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Deformation Twinning in Metals and Ordered Intermetallics-Ti and Ti-Aluminides M Deformation twinning in metals and ordered intermetallics-Ti and Ti-aluminides M. Yoo, C. Fu, J. Lee To cite this version: M. Yoo, C. Fu, J. Lee. Deformation twinning in metals and ordered intermetallics-Ti and Ti- aluminides. Journal de Physique III, EDP Sciences, 1991, 1 (6), pp.1065-1084. 10.1051/jp3:1991172. jpa-00248626 HAL Id: jpa-00248626 https://hal.archives-ouvertes.fr/jpa-00248626 Submitted on 1 Jan 1991 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. (1991) Phys. 1065-1084 J. 1991, III1 1065 PAGE JuiN Classification Physics Abstracts 61.70N 62.20F 62.20D twinning intermetallics-Ti ordered Deformation metals and in Ti-aluminides and (1) C. Fu K. Yoo, H. and J. M. L. Lee (2) Ridge, 37831,6115, Ridge Laboratory, Division, Oak TN Oak National Metals Ceranlics and U-S-A- 1990) (Received19 accepted September 1990, 4 June cons6quences maclage ductilitd des la ddformation de fracture Rksumk.-Los la la et par sur cristallographie, intermdtalliques fonction alliages ordonnds dtudides de de mdtaux la et sont en systdmatique l'dnergie cindtique maclage. analyse ddformations dtd faite de des Une la et a par en comparaison systdmes Ti~Al, consid6rant Ti, TiAl moddles. En le A13Ti quatre et avec comme important maclages intrinsdque difficultd Ti, maclages dans observds T13Al des de nombre dans la dragging shuming interchange mdcanisme de de mdcanisme rationalisde d'« Un est tenure ». en l'origine physique faible mobilitd explique la des fault» bask l'interaction de «torque» sur (I Ii) qui macles 112. superdislocations dans TiAl conduire k nucldation des la vissdes peuvent glissement conjugude le alliages AJ3Ti, la made relation TiAl Dans les tels la et entre et compatibilitd la ddformation importante fagon contraintes (ordinaire) I lors des de contribue de la d'addition tempdrature. bdndfiques potentiels dldments plastique efiets lids k des haute £ Des sur dgalement discutds. maclage le de sont processus ductility and ordered twinning strength of metals of deformation in the and The role Abstract. kinetics crystallography, energetics and of the of alloys examined basis interrnetallic is on taking four TiAl, systematic analysis by and Ti, twinning. T13Al, A made A13Ti deformation is as difficulty twinning Ti, of comparison twinning in intrinsic in profuse with the model In systems. (SISF) dragging shuffling interchange fault A the mechanism. rationalized is of T13Al in terms mobility of physical for the explains the low mechanism interaction based the torque source on [1Ii] (1Ii) TiAI and nucleation. TiAI, twin In superdislocations in which lead to may screw twin-slip relationship important contribution conjugate (ordinary) makes alloys, A13Ti the to an Potentially alloying high,temperature plasticity. beneficial additions compatibility for the strain to twinning discussed. promote are Sciences, (I) Energy of Office Basic U-S- Sciences, sponsored Division of Materials by Research the Systems, Energy DE-ACo5-840R21400 with Martin Marietta Energy, under Department of contract Inc. Metallurgical Engineering, Michigan Department Materials of and address.- Permanent (2) Houghton, 49931, Technological University, U-S-A- MI PHYSIQUE M loss JOURNAL DE III 6 InUoducfion. 1. plastic of twinning principal deformation in Slip modes the low and temperature two are published monograph twinning deformation than crystalline solids. The last two on more was Mahajan [I], subject given and Williams general by and last the decades review ago on a was effectively twinning experimentally strengthen deformation observed that It is [2]. can a clarify under circumstances others. weaken it under To material and this apparent some twinning hexagonal dichotomy role of fracture of cubic metallic and the and in understand to objectives twinning symposium the deformation materials of [3]. the last More were on importance twinning recently, deformation of of and the behavior the in fracture of awareness alloys particularly tetragonal interrnetallic the in and Llo ordered has D0~~ type type grown, crystal [4]. structures twinning strength The of this deformation the role of in the is and to purpose paper survey ductility alloys, compounds point intermetallic metals, of ordered and from theoretical of a adopted develop intended, general approach overview here is While is the view. to a a analysis twinning plays alloys interrnetallic in of the model metal and selected systematic role approach specific binary this Ti-Al. motivation for establish The is from system, to e-g- a one unique physical properties analysis consisting electronic basis for the and of the common specific bonding binary Experimental characteristics of data mechanical the atomic system. on properties description and deformation first brief Inicrostructure section reviewed in 2. A are crystallography twinning given by energetic 3, the of section followed the in is of -and kinetic analyses growth Finally, twinning in of nucleation and section the role of twin 4. in toughness plastic generalized flow 5, and fracture is effect assessed in section and the of alloying twinning discussed section is in 6. on hexagonal close-packed (hcp) alloys metal, a-Ti, a~-Ti~Al, interrnetallic A and three of ~+ single-phase Al3Ti TiAl, Figure four models for the chosen the and overview. I present are as crystal (A3, four D019, Llo and shows the and axial ratios the D0~~) types structure (cla) model superlattice of four materials is The these temperature. D01~ structure at room a ~hcp) having long-range of only perpendicular derivative the order A3 direction in the type to consisting Llo tetragonal face-centered The is layers atomic the axis. of the type structure c perpendicular along is Ll~ axis. stacked the The related unit cells D0~~ type type two to to c antiphase (APB) 1/2[110](001) boundary (001) with of plane. the axis other type at every an c SUength ductility. 2. and yield strength TEMPERATURE 2.I material The of STRENGTH. DEPENDENCE YIELD oF a yielding parabolic behavior which shows the usually by defined the of is normal type stress, ~ corresponding strain, specific off-set of the four each For model 2 10~ to e-g- «~, a x e = yield dependence the of the by determined has been temperature stress, systems, «~, crystals. along single Figure schematically the axis of experimental compressing shows 2 the c Al3Ti reported [6], [7], Ti TiAl and applied [5], T13Al for where data the [8] strain rate was ~ ~positive) dependence noIninally anomalous An of 10~ in temperature all d s~ «~ occurs = plays twinning important and deformation Ti~Al. role in all Al~Ti, except except an peak the deformation K, mode a) below the 650 temperature, Ti-At temperatures T~ = (ll13) (l122) hand, twinning On (above entirely by the other [5]. 90 almost 9b) at was (c ) (10-30 fb) mode major slip the minor above the mode and temperatures was T~, + was a (10fl) (10f2) strength yield reported twinning Therefore, rise and fall of for Ti the the [5]. M DEFORMATION 6 TWINNING METALS IN lo67 (h.c.p.) A3 DO~~ =1.59) (cla O.80) cla Ti Ti~Ai = L'o .D°zz o o °o ~. ~ i o oh o ~ a-~ TiAi~(Cla=2.23) TiAi(Cib=1.02) phases Ti-Al Crystal Fig. model in of the four 1. system. structures slip involving displacement twinning transition be related from the apparent to to may an (c ) along directions. vector + a yield strength Ti~Al b) T13Al-The compressive higher is measured much in than that Ti in (Fig. 2). peak shear Ti, The about 9b of the 1130 is modulus which is of K 4 stress at T~ a = twinning strength. Ti~Al of theoretical observed has been in the [6, The No 9]. measure (1ill) yield (1122) mobility Ti~Al anomalous in behavior is attributed edge of the low (~) to superdislocations, higher originating glide increasing resistance with temperatures most probably pairs from climb superpartial difficulty dissociation the of for [6]. of The reason twinning Ti~Al later will be in in discussed section 3.3. c) figure TiAI-The dashed single from shown in crystals obtained 2 Ti4sAls4 [7]. curve was proposed physical number A positive source(s) rationalize the of theories have the been of to [10-14], dependence of but in TiAl dislocation which model for temperature accounts «~ no experimental observations, dependence of orientation the details such the the and strain- as ii sensitivity developed. Although twinning importance (111) ill been of of the has rate «~, twinning, plastic generally acknowledged so-called ordered [4], deformation is in (~), no specific twinning yield strength in anomaly been role of has elucidated. the The Miller indices fundamental referred h,c.p. the (3) lattice. to are The indices referred the f.c.c. lattice. (~) to are PHYSIQUE M JOURNAL DE 6 III lo68 z-o COMPRESSION ALONG THE C-AXIS ~ ' l.5 600 k ' ~ l.O ~ j ~~ ~"", ~, ' ~ 400 i ', ' Ti ', # ' ~ ' ', O.5 ~ ', ZOO . ', ~ ' j~ O O 400 ZOO 600 800 lOCO120044OO TEMPERATURE, T K strength yield single dependence compressive Ti Fig. 2.-Temperature of the of and Ti-a1ulninide crystals. yield Al~Ti-This compound strength d) shows weakest four the the systems among dependence major considered, it of The deformation normal and shows temperature. «~ a on ill along ( ii twinning slip ii augmented ii10] ordered the which 00] by mode is it is the and I [8, directions 15]. shows Figure of TEMPERATURE the 2.2 3 FRACTURE DEPENDENCE STRAIN.
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