COST 507 - Repositório Aberto da Universidade do Porto

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Introduction The project of our unit concerns the study of "Thermodynamics and phase equilibria in the system Al-Mg-Cu-Zn-R-(Ni. Mn) with R=rare earth. Effects of rare earth additions to Al-based or Mg-based alloys). Within the coordination group A, work is being carried out on phase equilibria determination and thermochemical measurements of specific rare earth containing subsystems. On the same systems work is also in progress in the framework of coordination group C (see the corresponding report). In the following a summary is reported of the results obtained in the investigation of Al and Mg alloys. Aluminium Alloys [96Borl] The standard molar enthalpies of formation for the different solid La-AJ and Yb-Al alloys have been measured by means of direct calorimetry. The composition and equilibrium state of samples were checked by micrographie and X-ray diffraction techniques. The following values have been obtained (kJ/mol of atoms): LaAl, Af orm H°= -46.0±2; LaAl 2 , A foral H°= -50.5.012; LaAl 3 , A form H°= -44.012; La 3 Al n , A f0rin H o = -41.012; YbAl 2 , A f0nn H o = -39.5.012; YbAl 3 , Af oral H°= -32.5.012. Experimental results are discussed and compared with literature data. [96Bor2] Several applications of selected R-Al-M (R=rare earth metals, M=transition metal) alloys for their typical characteristics such as magnetic properties have been discussed in order to gain information on stable and metastable phases of these systems. A systematic study on the reactivity of the R-Al and R-Al-Ni alloys has been started. To this end calorimetrie techniques, X-ray diffraction and microscopy analyses are used. The results so far obtained for selected Ce-Ni and Ce-Al-Ni alloy compositions have been illustrated and discussed. [96Bor3] The results obtained for Ce-Al-Ni system have been presented. The thermochemical investigation was performed with an isoperibol aneroid calorimeter. The ternary phases were synthetised directly in the calorimeter, starting from a mixture of the finely powdered components enclosed in a gas-tigth inox crucible sealed by electric welding. Metallographic analysis, electron probe microanalysis (ΕΡΜΑ), X-ray diffraction analysis (powder diffraction) were used to characterised all samples, to ascertain the absence of unreacted metals and to assess their equilibrium state. The data so far obtained for characteristics sections have been reported, discussed and compared with those relevant to the involved binary alloys. [96Gam] The R-rich regions of the [Rare Earth + Al] systems (with R=La, Ce, Pr, Nd) have been recently reinvestigated by using the differential thermal analysis techniques and the melting behaviour of the (R+Al) alloys with a particular attention to the thermodynamic properties has been undertaken. In this paper the first results of the measurements of the molar heat capacity (Cp°) of some [La+Al], [Ce+Al], [Pr+AJ] and [Nd+Al] alloys are presented and discussed. - 148 -
[96Sac] The Rrich regions of the RAl systems (R=La, Ce, Pr, Nd) have been studied by using thermal analysis (DTA), metallographic analysis, quantitative electron probe microanalysis (ΕΡΜΑ) and Xray examinations (XRD). The coordinates of the Rrich eutectics, the lowering of the allotropie transformation temperatures of the rare earth metals by additions of Al and melting behaviours of the Rrich compounds have been particularly investigated. The terminal aluminium solubilities in the different rare earth metals and the relative stabilities of the catatectic and eutectoid equilibria have been discussed. Magnesium Alloys [96Cac] A systematic study of the enthalpy of formation of binary RMg alloy considering, to begin with, the systems formed with La, Ce, Pr, Nd, Sm and Yb, have been started. These systems were investigated by high temperature direct reaction drop calorimetry by using an instrument built in our laboratory and previously described. Other experimental methods employed in this research were Xray diffractometry, optical and electron microscopy. Preliminary results concerning the enthalpy of formation of some alloys at the compositions RMg, RMg2 and RMg3 in the mentioned systems have been presented and discussed. [96Fla] The structural and magnetic properties of a series of novel compounds in the ternary CeMgY system have been studied by Xray diffraction, SQUID magnetometry and XAS spectroscopy. The crystal structures of the compounds Ceo.33Yo.67Mg 2 and Ceo.49Yo.5iMg4.7 have been refined by the Rietveld technique. Magnetic data are consistent with a tripositive ground state 2 F¡a for the cerium atom. The XAS measurements confirm this result. Crystal field effects are apparent in the magnetic data at temperatures below about 50 Κ in the compounds with higher Ce concentration. 149
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European Commission COST European c
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European Commission COST European c
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Preface The Final Workshop of the C
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COST 507 STRUCTURE Measurement and
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GRl: Mirtee S.A., Volos Mr.P.Polati
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D9 Dll Fl GR2 II NI S3 SF1 "Thermop
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A Summary of the COST 507 Action an
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Aluminium-based systems Titanium-ba
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An Example using the COST 507 Datab
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Appendix COST 507: Some Key Meeting
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Al - 0.5 Fe, 1 Mg, 0.8 Mn, 0.2 Si (
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Fig 4 Aluminium beverage cans. The
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Fig 6 High pressure compressor vane
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INTRODUCTION All of us are aware of
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In the interaction with materials a
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There was a first warning more than
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Some time ago, the well-known physi
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Today there is a whole range of ins
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The dimension of this reservoir inc
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REFERENCES [ 1 ] G. Petzow, "Man, M
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Trends in Application of Materials
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Raw Materials The Cycle of Material
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i LÌ i.'»Af·· iù^ VV.V.X. iTTa
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1600 OJ 1200 .« 1100 d 1000 900 Si
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Al Phase Relations in the Aluminium
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oundaries of the single phase regio
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Table 1 : Crystallographic Data of
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order to facilitate the evaluation
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(especially around 33 at% Mg) in or
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3.System Ti-Sn-Al-N. The investigat
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6) N.Durlu, U.Gruber, M.Pietzka, H.
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Summary of final report Directional
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calculate the thermodynamic mixing
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Introduction It is the aim of this
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Thermodynamic evaluations for high
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Figure 5 presents the calculated li
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There is a complete lack in the lit
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a.B5 ø.ia 0.15 0.20 0.25 0.30 0.35
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700 [53Phi] 800 +[90Kuz21 ]iquld a
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Thermodynamic Assessments, Experime
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AIN and TiNi_ x is also given. Vari
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satisfied the three requirements of
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84Bey R. Beyers, R. Sinclair, and M
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Material and Methods 2.1 Fabricatio
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3.4 Electronmicroscopy (SEM) and X-
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Tab. 3: Density of the Ti20Albase
Page 101 and 102: Tab.5. continued TÌ20A1 5CulONi Ti
Page 103 and 104: Fig. 3: ESMA and Xray diffraction
Page 105 and 106: Fig.7: Wetting angle of Ti 15A1 lOC
Page 107 and 108: Thermophysical Properties of Light
Page 109 and 110: Tab.2 Chemical composition of terna
Page 111 and 112: 700 (AI)+AIFeS¡«_600 KS1275.1 l
Page 113 and 114: 4.2 Thermal conductivity of industr
Page 115 and 116: 4.3 AlSiZn alloys Electrical re
Page 117 and 118: 94Jar/Bra G.Jaroma-Weiland, R.Brand
Page 119 and 120: MgZn9 (C 14) and Mg2Zn u in the Al
Page 121 and 122: The three Laves phases were describ
Page 123 and 124: References [13Ege] G. Eger, Z. Meta
Page 125 and 126: 0.30 0.35 0.40 0.45 0.50 mole fract
Page 127 and 128: □ [48Koe] 600 500 400 0 0.1 0
Page 129 and 130: MggZn,, this work □ Single phase,
Page 131 and 132: Temperatures in °C 0.05 0.10 mole
Page 133 and 134: Table 2 : Alloy compositions Alloy
Page 135 and 136: All. Dy 50 Cpexp °C Cpadd Table 5
Page 137 and 138: Zn ¿Kl Si Fig. 2 : Position of the
Page 139 and 140: 22.5 ■■ 7.5 Temperature ICI Tem
Page 141 and 142: .to 2.5 "lõõ soo iÍOõ dOõ rtõ
Page 143 and 144: GR2 Differential Scanning Calorimet
Page 145 and 146: Time (x10 3 sec) Fig. 1. DSC Thermo
Page 147 and 148: solidification. It can be seen that
Page 149 and 150: 4. Conclusions Differential scannin
Page 151: COST 507 - ROUND Π UNIT II SEZIONE
Page 155 and 156: List of publications in the framewo
Page 157 and 158: 2Contributions: oral or posters p
Page 159 and 160: 1996 REPORT 2 s ' PART: ACTIVITY CA
Page 161 and 162: [96Sei] Excess Gibbs energy coeffic
Page 163 and 164: List of publications in the framewo
Page 165 and 166: Proc. :7 th Meeting on "Syntheses a
Page 167 and 168: 2.1 Solid solubility measurements T
Page 169 and 170: eviews by Rivlin and Raynor [81 Riv
Page 171 and 172: inaires. Thesis, Universite Scienti
Page 173 and 174: Table 1. Review of the ternary phas
Page 175 and 176: L) Liq+bcc=FeSi+t_1 M) Liq+t 1=FeSi
Page 177 and 178: Extrapolations based on Ti-C-N S3 B
Page 179 and 180: value has been accepted in all thre
Page 181 and 182: with high precision whereas Jonsson
Page 183 and 184: only fit the hightemperature asym
Page 185 and 186: Jonsson combined his descriptions o
Page 187 and 188: Table II. Solubility product of TiC
Page 189 and 190: Ti-C, Z.Metallkd. 86 (1995) 5 319
Page 191 and 192: 1000 1500 2000 2500 3000 Τ (K) Fig
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Page 195 and 196: M^øD^ O Kelley(1944) • Kelley an
Page 197 and 198: — cale, with Dumitrescu (1997) -
Page 199 and 200: € gfc-π m-, .-π-, π-π .-saa J
Page 201 and 202: +graph 0 TiN 0.2 0.4 0.6 X TiC 0.8
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Binder et al (1992) TiN 1423 K ■
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0.08 600°C 700°C 800°C 900°C 10
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[59Sto]: Ä600°C □ 70D°C O8Q0°
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2000 Cale, with Saunders (1997) —
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An Experimental Investigation of th
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An Experimental Investigation of th
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211 -
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EXPERIMENTAL INVESTIGATION OF THE C
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Fig.1 SEM micrographs of CuMgZr
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■ 888 24 HSM^«" 16—19 3 À I
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Thermodynamic Evaluations of the Al
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Fcc_Al aves_C15 ONU ΔΝ12 αΝ13
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2.2 Assessment The optimisation of
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0.50 0.45 CulOZr7/ 0. 40 Or ^ 0.3
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References [71Kri] Kripyakevich, P.
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Kejun Zeng and Marko Hämäläinen,
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for detennining phase boundary and
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Table 2 Al-Fe-Mn results wt%Fe 0.5
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•00 Γ Ι I I I ~ LIQUID S^ 7iO
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the observed A2-B2 ordering. This p
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1473K Ahmed & Flower [94 Ahmi] 0.2
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900K Paruchuri & Massalski [91Par]
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BCC_B2#2 TI3RL TIPL BCC B2#2 TIRL
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0.2 0.3 0.4 0.5 X(LIQ,V) Figure 15
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1 Introduction and Overview of the
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at least 95% by Fe, possibly 99%, a
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8 References 43Phi H W L Phillips,
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1050 1000 Isopleth, Al - Si - 4 wt
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Al-Mn-Si 873 K 0.90 Liquid 0.80 0.7
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A Thermochemical Assessment of Data
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certainly due to the appearance of
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Materials Science Centre, November
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1400 Al-Mn Fig 2 Calculated partial
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1000 ι AlMn I Ι 950 Liquid E ω
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Al-Fe-Mn 843 K 0.90 0.80 0.70 0.60
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AlFeMn section at 2 wt% Mn co
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0.50 0.45 0.40-1 LU £ 0.35 LU 0.30
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European Commission EUR 18171 —CO
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NOTICE TO THE READER Information on
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