Views
5 years ago

2 µm - eTheses Repository - University of Birmingham

2 µm - eTheses Repository - University of Birmingham

2 µm - eTheses Repository - University of

Pressure Infiltration Behaviour and Properties of Aluminium Alloy - Oxide Ceramic Preform Composites University of Birmingham Birmingham B15 2TT United Kingdom July 2009 by Bernd Arthur Huchler A thesis submitted to the School of Metallurgy and Materials College of Engineering and Physical Sciences of The University of Birmingham for the degree of Doctor of Philosophy

  • Page 2 and 3: University of Birmingham Research A
  • Page 4 and 5: ACKNOWLEDGEMENTS I express my deepe
  • Page 6 and 7: 3.3.10. Microstructural investigati
  • Page 8 and 9: NOMENCLATURE Symbol Meaning α shap
  • Page 10 and 11: Symbol Meaning θ0 initial contact
  • Page 12 and 13: 1. INTRODUCTION To make a lightweig
  • Page 14 and 15: The present work concentrates on pr
  • Page 16 and 17: material (6) . The oxide film is fo
  • Page 18 and 19: Mg alloys, Mg oxidizes preferential
  • Page 20 and 21: with T, the actual temperature and
  • Page 22 and 23: Figure 2.4 Binary phase diagram of
  • Page 24 and 25: The size and morphology of the meta
  • Page 26 and 27: The strengthening in MMCs is divide
  • Page 28 and 29: Long et al. (49) proposed a model t
  • Page 30 and 31: appropriate specimen preparation me
  • Page 32 and 33: The main factors controlling the el
  • Page 34 and 35: and contributes to premature fatigu
  • Page 36 and 37: 2.2. Static wetting in metal-cerami
  • Page 38 and 39: The wetting behaviour of Al2O3 by l
  • Page 40 and 41: an intimate aluminium oxide film. I
  • Page 42 and 43: time dependence of dynamic angles.
  • Page 44 and 45: monolayer of the most stable reacti
  • Page 46 and 47: Standard free energy of formation
  • Page 48 and 49: In the case of a), the diffusion ra
  • Page 50 and 51: Thus the wettability of a liquid wi
  • Page 52 and 53:

    where γHg is the surface tension o

  • Page 54 and 55:

    (ii) for non-isothermal infiltratio

  • Page 56 and 57:

    non-wetting fluid, as a function of

  • Page 58 and 59:

    Figure 2.13 shows an Al-Saffil MMC

  • Page 60 and 61:

    Apart from permeability, the specif

  • Page 62 and 63:

    Figure 2.15 Microstructure of ceram

  • Page 64 and 65:

    has to be applied. In general, infi

  • Page 66 and 67:

    2.5.2. Squeeze casting infiltration

  • Page 68 and 69:

    On the other hand, if the outlet of

  • Page 70 and 71:

    measurable compression in the resul

  • Page 72 and 73:

    2.6. Aims and Objectives Particulat

  • Page 74 and 75:

    where νi is the stoichiometric coe

  • Page 76 and 77:

    Si alloy of the type EN AC-AlSi12Fe

  • Page 78 and 79:

    a) contact heating Al-alloy b) heat

  • Page 80 and 81:

    3.3.1. Preform ceramics The seleced

  • Page 82 and 83:

    Table 3.5 Specified properties of t

  • Page 84 and 85:

    3.3.4. Sintering Sintering of the g

  • Page 86 and 87:

    3.3.6. Pore structure The pore size

  • Page 88 and 89:

    of 0.05 to 0.25 MPa to determine th

  • Page 90 and 91:

    preform compression. The relative v

  • Page 92 and 93:

    die casting methods, a constant flo

  • Page 94 and 95:

    After solidification under pressure

  • Page 96 and 97:

    The plunger velocity of the die cas

  • Page 98 and 99:

    temperature difference between a re

  • Page 100 and 101:

    account the compliance of the test

  • Page 102 and 103:

    4. RESULTS 4.1. Thermodynamic calcu

  • Page 104 and 105:

    calcium and aluminium in the stoich

  • Page 106 and 107:

    4.2. Contact angle 4.2.1 Influence

  • Page 108 and 109:

    account the error in contact angle

  • Page 110 and 111:

    emoving the droplet of the IM-AF co

  • Page 112 and 113:

    shoulder between 60 and 70% cumulat

  • Page 114 and 115:

    4.3.3 Microstructure Figure 4.13 a)

  • Page 116 and 117:

    fraction to be calculated as shown

  • Page 118 and 119:

    place which was attributed to the c

  • Page 120 and 121:

    compromise had to be found, where t

  • Page 122 and 123:

    fabricated in the target porosity r

  • Page 124 and 125:

    (AGPC15). That of MOPC20 could not

  • Page 126 and 127:

    As shown in Figure 4.21 a), the cav

  • Page 128 and 129:

    4.23 b). The immediate border of th

  • Page 130 and 131:

    Compared to the incremental diagram

  • Page 132 and 133:

    fraction of coarse pores. The alter

  • Page 134 and 135:

    Specific surface area S (m²/g) s S

  • Page 136 and 137:

    is attributed to the relatively lar

  • Page 138 and 139:

    As shown in Figure 4.33, the uniaxi

  • Page 140 and 141:

    Relative volumetric compression c i

  • Page 142 and 143:

    Specific permeability KK(m²) s / m

  • Page 144 and 145:

    4.7. Constant pressure infiltration

  • Page 146 and 147:

    a) b) Figure 4.40 Cross sectional m

  • Page 148 and 149:

    The mean saturation along the x-axi

  • Page 150 and 151:

    grey areas consisted of an intermet

  • Page 152 and 153:

    estarted when the pressure dropped

  • Page 154 and 155:

    gradient of the curve changed was o

  • Page 156 and 157:

    4.8.5 Advancing infiltration with a

  • Page 158 and 159:

    organic additive in the preform pro

  • Page 160 and 161:

    The low magnification micrographs o

  • Page 162 and 163:

    The bimodal porosity in the preform

  • Page 164 and 165:

    The sintering temperatures of the M

  • Page 166 and 167:

    Compared to the micrographs of the

  • Page 168 and 169:

    shear stresses in this brittle phas

  • Page 170 and 171:

    eactions in the MMC samples are ind

  • Page 172 and 173:

    The microstructure after heat treat

  • Page 174 and 175:

    4.8.11 Homogeneity of MMC infiltrat

  • Page 176 and 177:

    IM I 165 G B 2 10 2 10 µm µm Figu

  • Page 178 and 179:

    Figure 4.68 Optical micrograph take

  • Page 180 and 181:

    Y-Z Z Y X 10mm X-Y X-Z Figure 4.70

  • Page 182 and 183:

    In order to determine the effects o

  • Page 184 and 185:

    deviations were 0.01 whereas larger

  • Page 186 and 187:

    There were minor differences in the

  • Page 188 and 189:

    esulting MMCs were checked using no

  • Page 190 and 191:

    AODY30IS showed the lowest σ0 valu

  • Page 192 and 193:

    With a KIC of 9.5 MPa·m 1/2 , AOPC

  • Page 194 and 195:

    ww values of all MMCs were less tha

  • Page 196 and 197:

    a) b) Wear path x 2 200 2 200 µm

  • Page 198 and 199:

    (DSQC) (135) which was applied in t

  • Page 200 and 201:

    cast A356 (178) (12 MPa·m 1/2 ). T

  • Page 202 and 203:

    literature (149) . The moduli of th

  • Page 204 and 205:

    Even though air is forced out of th

  • Page 206 and 207:

    In summary, the large surface area

  • Page 208 and 209:

    fulfilled when the total porosity

  • Page 210 and 211:

    attributed to the finer reinforceme

  • Page 212 and 213:

    material, similar to that resulting

  • Page 214 and 215:

    the 10% uncertainty of the model (1

  • Page 216 and 217:

    indicating stronger bonds to crack

  • Page 218 and 219:

    coarsening of the fine MgO, as indi

  • Page 220 and 221:

    characteristic DSQC infiltration cu

  • Page 222 and 223:

    Equation 20, reduces P0. However, B

  • Page 224 and 225:

    composites comprising a Ti3Al matri

  • Page 226 and 227:

    The macroscopic wetting angle data

  • Page 228 and 229:

    in all preforms during infiltration

  • Page 230 and 231:

    The reactive preforms TOPC20 and MO

  • Page 232 and 233:

    As a summary, P0 is shown as a func

  • Page 234 and 235:

    eactive preforms in order to determ

  • Page 236 and 237:

    In order to achieve low infiltratio

  • Page 238 and 239:

    Equation 27 leads to Equation 50, w

  • Page 240 and 241:

    −1 Δ j t j Δt p j−1 i−1 j p

  • Page 242 and 243:

    of 0.023 m and nil saturation behin

  • Page 244 and 245:

    The calculations at a Pappl of 1.2

  • Page 246 and 247:

    esulted. This was the case for the

  • Page 248 and 249:

    7. The interpenetration fineness, w

  • Page 250 and 251:

    7. FUTURE WORK The preform processi

  • Page 252 and 253:

    22. Li, J.G., Coudurier, L. and Eus

  • Page 254 and 255:

    64. Hoffmann, M., Skirl, S., Pompe,

  • Page 256 and 257:

    107. Travitzky, N.A. and Shlayen, A

  • Page 258 and 259:

    147. Eriksson, G. and Hack, K. :

PDF File 2 - University of Alabama at Birmingham
no· l'2-'1t1 - Repository - Texas A&M University
eTheses Repository - University of Birmingham
chapter 1 - eTheses Repository - University of Birmingham
MODULE 2 - eTheses Repository - University of Birmingham
eA - eTheses Repository - University of Birmingham
eTheses Repository - University of Birmingham
eTheses Repository - University of Birmingham
Caroline Winstanley - eTheses Repository - University of Birmingham
epinician precepts - eTheses Repository - University of Birmingham
Witch Shoes - eTheses Repository - University of Birmingham
pains of sin - eTheses Repository - University of Birmingham
B - eTheses Repository - University of Birmingham
Cymbeline - eTheses Repository - University of Birmingham
here - eTheses Repository - University of Birmingham
View - eTheses Repository - University of Birmingham
J - eTheses Repository - University of Birmingham
B - eTheses Repository - University of Birmingham
1 - eTheses Repository - University of Birmingham
5% - eTheses Repository - University of Birmingham
Table of Contents - eTheses Repository - University of Birmingham
Anne Bevins 606082 - eTheses Repository - University of Birmingham
attending to others - eTheses Repository - University of Birmingham
ford madox brown - eTheses Repository - University of Birmingham
chapter 1 - eTheses Repository - University of Birmingham
THE GOD–MAN - eTheses Repository - University of Birmingham
Engineering texts - eTheses Repository - University of Birmingham
Life on Wings - eTheses Repository - University of Birmingham
ford madox brown - eTheses Repository - University of Birmingham
Intrinsic Naturalism - eTheses Repository - University of Birmingham