CaH2-TiO2

㄀ 38 ो
2009 ᑈ
㄀ 12 ᳳ
12 ᳜
⿔᳝䞥ሲᴤ᭭ϢᎹ⿟
Vol.38, No.12
December 2009
RARE METAL MATERIALS AND ENGINEERING
CaH2-TiO2-Al ԧ㋏ࠊ໛ TiAl ড়䞥ডᑨᴎࠊⱘ᥶䅼
‫ڜڲ‬഑ 1ēܑ
ཧ 1ēюစࢌ 2ēܑ໌਩ 1
(1. ≜䰇⧚Ꮉ໻ᄺˈ䖑ᅕ ≜䰇 110168)
(2. ≜䰇㟾໽ϝ㧅≑䔺থࡼᴎࠊ䗴᳝䰤݀ৌˈ䖑ᅕ ≜䰇 110179)
ᨬ
㽕˖䗮䖛⛁࡯ᄺ䅵ㅫৃⶹˈ೼ CaH2-TiO2-Al ԧ㋏Ё⫼䖬ॳᠽᬷ⊩ࠊ໛ TiAl ড়䞥ᰃৃ㛑ⱘDŽ䆹ডᑨЎϔ㑻ডᑨˈ䞛
⫼⎆-೎᳾ডᑨḌ῵ൟ᥶䅼݊ডᑨᴎࠊDŽ㒧ᵰ㸼ᯢˈTiO2 䖬ॳ៤㒃䞥ሲ Ti 䴲ᐌ䖙䗳ˈϡᰃডᑨⱘ᥻ࠊℹ偸ˈ⬠䴶࣪ᄺড
ᑨЎডᑨⱘ᥻ࠊ⦃㡖DŽডᑨⱘ㸼㾖⌏࣪㛑Ў 76.84 kJ·mol-1DŽᔧ CaH2 ⱘ䞣Ў⧚䆎䅵ㅫ䞣ⱘ 1.5 ‫ס‬ᯊডᑨ‫˗ߚܙ‬Al ㉝ⱘ㉦
ᑺᇍডᑨ≵᳝ᕅડ˗ডᑨ⏽ᑺЎ 1423 Kǃডᑨᯊ䯈Ў 8 h ᯊˈTiAl ড়䞥ⱘ䕀࣪⥛᥹䖥 100%DŽ
݇䬂䆡˖CaH2-TiO2-Al ԧ㋏˗TiAl ড়䞥˗ডᑨᴎࠊ
Ё೒⊩ߚ㉏ো˖TF123.1+21
᭛⤂ᷛ䆚ⷕ˖A
‫݋‬᳝ γ Ⳍ㒧ᵘⱘ TiAl ড়䞥ˈ⬅Ѣ݊ᆚᑺᇣǃᔎᑺ
᭛ゴ㓪ো˖1002-185X(2009)12-2151-04
佪‫ߚܜ‬㾷៤ Ca Ϣ H2ˈCa ੠ Al Ў⎆ᗕˈϨ Ca 㪌⇨य़
催ǃᡫ㷩ব㛑࡯ᔎǃ催⏽࡯ᄺᗻ㛑੠ᡫ⇻࣪ᗻӬᓖ
䕗催ˈTiǃTiO2ǃCaOǃTi3AlǃTiAl ੠ TiAl3 ഛЎ೎ᗕDŽ
ㄝ⡍⚍ˈᏆ䍞ᴹ䍞ᓩ䍋৘೑⾥ᄺ⬠੠ᎹϮ⬠Ҏ຿ⱘ݇
ৃ㛑থ⫳ⱘডᑨঞ݊ডᑨঢ়Ꮧᮃ㞾⬅㛑䅵ㅫབϟ˖
⊼
[1,2]
DŽᴀᅲ偠䞛⫼䖬ॳᠽᬷ⊩ࠊ໛ TiAl ড়䞥DŽᅗᰃ
ᇚ䖬ॳ TiO2 Ϣ⫳៤ TiAl ড়䞥㒧ড়೼ৠϔ䖛⿟ЁˈⳈ
᥹ࠊ໛ߎ TiAl ড়䞥ⱘϔℹ⊩DŽ䆹ᮍ⊩䆒໛ᡩ䌘ᇥǃॳ
ᴤ᭭៤ᴀԢǃ⫳ѻ਼ᳳⷁˈᑊϨᇍ⦃๗≵᳝∵ᶧDŽ
ᅲ
偠
ҹ TiO2 ㉝ǃCaH2 ㉝੠ Al ㉝Ўॳ᭭DŽᇚ TiO2 ੠
Al ҹ 1:1˄䋼䞣↨ˈϟৠ˅ⱘ䜡↨ˈϢ䗖䞣ⱘ CaH2
CaH2=Ca+H2↑
TiO2(s)+2Ca(1)+1/3Al(1)=2CaO(s)+1/3Ti3Al(s)
˄1˅
-1
∆G1=–370 530+39.205T (J·mol )
TiO2(s)+2Ca(1)+Al(1)=2CaO(s)+TiAl(s)
˄2˅
-1
∆G2=–416 496+49.82T (J·mol )
TiO2(s)+2Ca(1)+3Al(1)=2CaO(s)+TiAl3(s)
˄3˅
-1
∆G3=–506 014+87.95T (J·mol )
೒ 1 Ўডᑨ˄1˅ǃ˄2˅੠˄3˅ⱘঢ়Ꮧᮃ㞾⬅㛑
⏋ড়ഛࣔˈ೼ϔᅮय़࡯ϟࠊ៤ሎᇌЎ 10 mm×10 mm×
᳆㒓ˈ∆G1>∆G2>∆G3DŽৃⶹ˖೼ CaH2-TiO2-Al ԧ㋏Ёˈ
50 mm ⱘḋഫDŽᇚ㺙᳝䆹ḋഫⱘഽථᬒܹⳳぎডᑨ఼
೼ 1112~1600 K ϟ䖬ॳᠽᬷডᑨ佪‫⫳ܜ‬៤ TiAl3DŽ⬅Ѣ
‫ˈݙ‬೼⇽⇨ֱᡸϟˈࡴ⛁㟇ϔᅮⱘ⏽ᑺ˄1112~1600 K˅ˈ
TiO2 Ϣ Al ⱘ䜡↨Ў 1:1ˈTiAl3 Ϣ Ti ᇚ䖯ϔℹডᑨ⫳
ᑊֱ⏽ϔᅮⱘᯊ䯈ˈՓ݊থ⫳䖬ॳᠽᬷডᑨˈ⫳៤ TiAl
៤ TiAlDŽ
ড়䞥DŽ
TiAl3(s)+2Ti(s)=3TiAl(s)
ᇚডᑨৢⱘ䆩ḋ䱣♝‫ैދ‬㟇ᅸ⏽ˈ⋫এ CaO ঞ໮
–300
–320
ডᑨ⫳៤ TiAlড়䞥㉝ⱘ䋼䞣
α =
× 100%
⧚䆎⫳៤ TiAlড়䞥㉝ⱘ䋼䞣
–340
–380
∆G3
–400
–420
1100
1300
1500
T/K
೼ CaH2-TiO2-Al ԧ㋏Ёˈ೼ 1112~1600 K ϟˈ䖬
ḍ᥂᭛⤂[4]ৃⶹ˖೼ 1112~1600 K ডᑨ⏽ᑺϟˈCaH2
∆G2
–360
⛁࡯ᄺߚᵤ
ॳᠽᬷডᑨ㛑⫳៤ TiǃCaOǃTi3AlǃTiAl ੠ TiAl3 [3]DŽ
∆G1
∆G/kJ·mol-1
ԭⱘ Caˈ㦋ᕫ TiAl ড়䞥DŽ
ḍ᥂ϟᓣ䅵ㅫ TiAl ড়䞥㉝ⱘ䕀࣪⥛ α˖
˄4˅
೒1
ডᑨ(1)ǃ(2)ǃ(3)ⱘঢ়Ꮧᮃ㞾⬅㛑
Fig.1
∆G of reaction (1), (2), (3)
ᬊࠄ߱〓᮹ᳳ˖2008-11-20˗ᬊࠄׂᬍ〓᮹ᳳ˖2009-06-02
԰㗙ㅔҟ˖䛁ᑓᗱˈཇˈ1963 ᑈ⫳ˈम຿ˈᬭᥜˈ≜䰇⧚Ꮉ໻ᄺᴤ᭭⾥ᄺϢᎹ⿟ᄺ䰶ˈ䖑ᅕ ≜䰇 110168ˈ⬉䆱˖024-24680841ˈE-mail:
[email protected]
g2152g
⿔᳝䞥ሲᴤ᭭ϢᎹ⿟
㄀ 38 ो
∆G4=–77 794–0.75T (J·mol-1)
100
90
K ⏽ᑺ㣗ೈ‫∆ˈݙ‬G4<0ˈ಴ℸ TiAl3 Ϣ Ti ডᑨ⫳៤ TiAl
80
α/%
೒ 2 Ўডᑨ˄4˅ⱘঢ়Ꮧᮃ㞾⬅㛑DŽ೼ 1112~1600
ᰃৃ㛑ⱘDŽ
70
೒ 3 Ў 1:1 ⱘ TiO2 ੠ Al Ϣ䗖䞣ⱘ CaH2 ೼ 1423 K
60
ϟֱ⏽ 8 h ⱘ䖬ॳᠽᬷѻ⠽ⱘ XRD ೒䈅DŽ䆹⫳៤⠽ᰃ
50
1.0 1.2 1.4 1.6 1.8 2.0
TiAl ড়䞥DŽ䇈ᯢ೼ CaH2-TiO2-Al ԧ㋏Ёˈ೼ 1112~
x
1600 K ϟˈ䞛⫼䖬ॳᠽᬷডᑨৃҹࠊ໛ TiAl ড়䞥㉝DŽ
೒4
⧚䆎࣪ᄺ䅵䞣↨ᇍ䕀࣪⥛ⱘᕅડ
ডᑨᴎࠊⱘ᥶䅼
Fig.4
TiO2 㹿䖬ॳ៤ Ti
೼䖬ॳডᑨ䖛⿟ЁˈCaH2 ೼ 1053 K ᯊߚ㾷៤ Ca
੠ H2ˈCa ᇚ TiO2 䖬ॳ៤㒃䞥ሲ TiDŽ䆹ডᑨ䖯㸠ᕫ䴲
ᐌ䖙䗳ˈϡᰃᭈϾডᑨⱘ᥻ࠊ⦃㡖DŽ
䖬ॳᠽᬷ⊩ࠊ໛ TiAl ড়䞥Ўϔ㑻ডᑨ
䖬ॳࠖ CaH2 ᖙ乏䖛䞣DŽḍ᥂ডᑨ˄1˅ˈ䖬ॳ 1 mol
ⱘ TiO2 䳔㽕 2 mol ⱘ CaH2DŽnTiO2:n2Ca=1:xDŽ݊Ё x=1
ᰃ⧚䆎࣪ᄺ䅵䞣↨ˈߚ߿প x=1.0ˈ1.5ˈ1.7 ੠ 2.0ˈ
೼ 1423 Kˈֱ⏽ᯊ䯈 8 h 䖯㸠ᅲ偠DŽTiAl ড়䞥䕀࣪⥛
Ϣ CaH2 ࡴܹ䞣ⱘ݇㋏བ೒ 4 ᠔⼎DŽ⬅೒ 4 ৃⶹˈ䱣ⴔ
CaH2 䞣ⱘ๲ࡴˈTiAl ড়䞥ⱘ䕀࣪⥛๲໻DŽᔧ CaH2 ⱘ
ࡴܹ䞣Ў⧚䆎䅵ㅫ䞣ⱘ 1.5 ‫ס‬ᯊˈTiAl ড়䞥ⱘ䕀࣪⥛
䖒ࠄ 95% ҹϞDŽПৢ‫ݡ‬๲ࡴ CaH2 ⱘ䞣ˈTiAl ড়䞥ⱘ
䕀࣪⥛᮴ᯢᰒ๲໻DŽ೼ডᑨ䖛⿟Ё CaH2 ⱘࡴܹ䞣Ў⧚
䆎䅵ㅫ䞣ⱘ 1.5 ‫↨ס‬䕗䗖ᅰDŽℸᯊ TiAl ড়䞥ⱘ䕀࣪⥛
Ϣডᑨ⠽⌧ᑺ᮴݇ˈ䇈ᯢ䖬ॳᠽᬷ⊩ࠊ໛ TiAl ড়䞥ড
ᑨᰃϔ㑻ডᑨ [5]DŽ
Al ㉝ⱘᠽᬷ
ҹϡৠ㉦ᑺⱘ Al ㉝Ўॳ᭭ˈᡞ 1:1 ⱘ TiO2 ੠ Al
Ϣ 1.5 ‫⧚ס‬䆎䅵ㅫ䞣ⱘ CaH2 ೼ϡৠⱘ⏽ᑺϟǃֱ⏽ϡ
ৠⱘᯊ䯈䖯㸠䖬ॳᠽᬷডᑨDŽ㒧ᵰབ೒ 5 ᠔⼎DŽৃҹ
ⳟࠄ˖೼ডᑨ⏽ᑺঞֱ⏽ᯊ䯈ⳌৠⱘᴵӊϟˈAl ㉝ⱘ
㉦ᑺᇍ TiAl ড়䞥ⱘ䕀࣪⥛≵᳝ᕅડDŽ಴Ўডᑨ⏽ᑺ催
Ѣ Al ⱘ❨⚍ˈAl ҹ䴲೎ᗕⱘᔶᓣখϢডᑨˈᬙ Al ㉝
ⱘ㉦ᑺᇍডᑨ≵᳝ᕅડDŽ
⹂ᅮЏ㽕ᠽᬷ‫ܗ‬㋴ᰃⷨおᭈϾডᑨⱘ෎⸔DŽTi Ϣ
Al ϸ㗙᳝ⴔⳌѦᠽᬷⱘ԰⫼ [6]ˈᔧ⏽ᑺԢѢ Al ⱘ❨⚍
ᯊˈTi Ϣ Al ⱘⳌѦᠽᬷ԰⫼ⳌᔧˈԚᰃ Ti ೼ Al Ёⱘ
೎⒊ᑺ䖰䖰ᇣѢ Al ೼ Ti Ёⱘ೎⒊ᑺˈ಴㗠 Al ᰃЏ㽕
ⱘᠽᬷऩ‫[ ܗ‬3]DŽᔧ⏽ᑺ催Ѣ Al ⱘ❨⚍㗠ԢѢ Ti ⱘ❨
⚍ᯊˈḍ᥂ߚᄤ䖤ࡼᄺৃⶹˈ⎆ᗕ Al ⱘߚᄤࡼ㛑ᇚᯢ
–-78.6
∆G/(kJ·mol)
-1
–-78.5
ᰒᦤ催ˈAl ᰃЏ㽕ᠽᬷ‫ܗ‬㋴DŽ೼ CaH2-TiO2-Al ԧ㋏Ёˈ
–-78.7
䖬ॳᠽᬷ⊩ࠊ໛ TiAl ড়䞥㉝ˈᰃ೼ 1112~1600 K ϟ䖯
–-78.8
㸠ⱘˈℸ⏽ᑺҟѢ Alǃ Ti ❨⚍П䯈ˈᬙ Al ᰃЏ㽕ᠽ
–-78.9
–-79.0
ᬷ‫ܗ‬㋴DŽ1423 K ⏽ᑺϟˈֱ⏽ 6 hˈAl ৥ Ti ᠽᬷⱘᔶ
–-79.1
1100 1200 1300 1400 1500 1600
T/K
䴶᳝ϔ㭘ሖ Al 㝰ˈᎺջЎ㒃䩯ˈЁ䯈Ў Ti-Al ড়䞥ऎDŽ
೒2
ডᑨ˄4˅ⱘঢ়Ꮧᮃ㞾⬅㛑
Fig.2
∆G of reaction (4)
30000
25000
䉠བ೒ 6 ᠔⼎DŽ೼䆹ডᑨ⏽ᑺϟˈAl Ў⎆ᗕDŽেջ㸼
䇈ᯢ೼䆹ডᑨ⏽ᑺϟ Al ᰃЏ㽕ᠽᬷ‫ܗ‬㋴DŽ
TiAl ড়䞥ⱘ⫳៤
⬅⛁࡯ᄺ䅵ㅫৃⶹˈTi ੠ Al ডᑨ‫⫳ܜ‬៤ TiAl3DŽ
100
Intensity/cps
TiAl
20000
0
20
α/%
15000
10000
5000
೒3
1373 K
21.6 ks
80
1373 K
14.4 ks
60
1273 K
14.4 ks
40
20
30
40
50 60
70
80
0
0
2θ/(°)
Fig.3
Effect of x on α
೼ 1423 K ᘦ⏽ 8 h ḋકⱘ XRD ೒䈅
XRD pattern of the sample heated at 1423 K for 8 h
1000
2000
3000
Al Powdery Granularity/µm
೒5
Fig.5
Al ㉝㉦ᑺᇍ TiAl ড়䞥䕀࣪⥛ⱘᕅડ
Effect of Al powder granularity on α
㄀ 12 ᳳ
䛁ᑓᗱㄝ˖CaH2-TiO2-Al ԧ㋏ࠊ໛ TiAl ড়䞥ডᑨᴎࠊⱘ᥶䅼
g2153g
㉝᳿ˈᬒ೼ഽථЁ˗೼ 1473 K ϟˈֱ⏽ 4 hDŽডᑨৢ
⺼এ㸼䴶 20 µm 㸼ሖࠊ៤ 1#䆩ḋˈ䖯㸠 X ᇘ㒓㸡ᇘẔ
⌟ˈ㒧ᵰབ೒ 9 ᠔⼎DŽৃҹⳟࠄˈ䆹䆩ḋࣙ৿ⱘ៤ߚ
᳝˖෎ԧ Tiˈডᑨѻ⠽ TiAl3ǃTiAl ঞᠽᬷࠄ Ti ‫ݙ‬䚼
᳾ডᑨⱘ AlDŽAl ⱘᄬ೼䇈ᯢ Al ᠽᬷࠄ Ti ‫ݙ‬䚼ৢᑊ≵
᳝ेࠏϢ Ti ডᑨˈ‫ݙ‬ǃ໪ᠽᬷⱘ䗳ᑺ໻Ѣ⬠䴶ডᑨⱘ
500 µm
೒6
Fig.6
䗳ᑺˈ‫ߚܙ‬䆕ᅲ⬠䴶ডᑨᰃ䖬ॳᠽᬷ⊩ࠊ໛ TiAl ড়䞥
ডᑨⱘ᥻ࠊ⦃㡖DŽ
Al ৥ Ti ᠽᬷⱘ SEM ✻⠛
ᇍѢ⬠䴶࣪ᄺডᑨЎ᥻ࠊ⦃㡖ᯊˈডᑨ䗳⥛ফ⏽
SEM image of Al diffusion to Ti
ᑺᕅડ䕗໻ˈ⏽ᑺ䍞催ˈডᑨ䗳⥛䍞໻˗ডᑨᯊ䯈䍞
⬅Ѣ Al ᰃЏ㽕ⱘᠽᬷऩ‫ˈܗ‬ডᑨሖ໪䴶ⱘ Al ঞ TiAl3
䭓ˈTiAl ড়䞥䕀࣪⥛䍞催DŽ䖭Ϣᅲ偠㒧ᵰⳌਏড়DŽҢ
Ёⱘ Alˈ䗮䖛ѻ⠽ሖᠽᬷࠄডᑨ⬠䴶Ϣ Ti 㒻㓁ডᑨ
೒ 7 Ёৃҹⳟࠄ˖ᔧডᑨ⏽ᑺЎ 1423 Kˈডᑨᯊ䯈Ў
⫳៤ TiAl ড়䞥DŽ
8 h ᯊˈTiAl ড়䞥ⱘ䕀࣪⥛᥹䖥 100%DŽ
ডᑨ᥻䗳⦃㡖ⱘ⹂ᅮ
㸼㾖⌏࣪㛑ⱘ䅵ㅫ
䞛⫼⎆-೎᳾ডᑨḌ῵ൟᴹߚᵤ䖬ॳᠽᬷ⊩ࠊ໛
TiAl ড় 䞥 ড ᑨ DŽ ϔ 㑻 ⎆ -೎ ᳾ ড ᑨ Ḍ ῵ ൟ ᭄ ᄺ 㸼 䖒
[7]
᳾ডᑨḌ῵ൟডᑨ䗳⥛ᮍ⿟ৃҹ㸼⼎Ў˖
k′t=1–(1–α)1/3
˄9˅
[7]
ᓣ Ў˖
ḍ᥂䰓㌃ሐРᮃ݀ᓣ 㸼㾖⌏࣪㛑䅵ㅫᓣЎ˖
1/3
2/3
t=A1α+A2[1–(1–α) ]+ A3[1–(1–α) –2/3α]
˄5˅
ᓣЁ˖A1ǃA2ǃA3 Ўᕙᅮ㋏᭄DŽ
Ea
1 1
×( − )
RT T2 T1
ln ( k '2 / k '1 ) = −
ᓣЁ˖ k' ——ডᑨ䗳⥛ᐌ᭄˗
ᭈϾডᑨ⬅໪ᠽᬷ԰⫼᥻ࠊᯊ˖
t = A1α
˄6˅
1/ 3
t = A2 [1 − (1 − α ) ]
Ea ——⌏࣪㛑˗
-1
R ——⇨ԧᐌ᭄ˈR=8.314 J·(K·mol) ˗
ᭈϾডᑨ⬅⎆-೎⬠䴶࣪ᄺডᑨ᥻ࠊᯊ˖
˄7˅
ᭈϾডᑨ⬅‫ݙ‬ᠽᬷ᥻ࠊᯊ˖
T——ডᑨ⏽ᑺDŽ
ḍ᥂೒ 8 ∖ߎϡৠডᑨ⏽ᑺϟˈࡼ࡯ᄺߑ᭄
t = A3 [1 − (1 − α )2 / 3 − 2 / 3α ]
˄8˅
f(α)=1–(1–α)1/3 ᇍডᑨᯊ䯈 t ⱘ᭰⥛ˈेডᑨ䗳⥛ᐌ᭄
ᡞ 1:1 ⱘ TiO2 ੠ Al Ϣ 1.5 ‫⧚ס‬䆎䞣ⱘ CaH2ˈ೼
2ǃ4ǃ6 ੠ 8 hˈTiAl ড়䞥䕀࣪⥛Ϣডᑨ⏽ᑺঞֱ⏽ᯊ
䯈݇㋏བ೒ 7 ᠔⼎DŽ
ᇚ೒ 7 Ё TiAl ড়䞥䕀࣪⥛ߚ߿ҷܹࡼ࡯ᄺᮍ⿟
1.0
f(α)=1–(1–α)1/3
1223ˈ1273ˈ1323ˈ1373 ঞ 1423 K ⏽ᑺϟˈֱ⏽ 0ǃ
˄6˅ǃ˄7˅ǃ˄8˅Ёˈডᑨᯊ䯈 t াϢᮍ⿟˄7˅
1423
1373
1323
1273
1223
0.8
0.6
K
K
K
K
K
0.4
0.2
0.0
᳔᥹䖥Ⳉ㒓݇㋏ˈབ೒ 8 ᠔⼎DŽ䇈ᯢ⎆-೎⬠䴶࣪ᄺড
0
2
ᇚϔഫ㒃䩯ಯ਼य़Ϟ䪱㉝ˈ໪䴶‫ݡ‬य़Ϟϔሖ CaH2
8
ডᑨᯊ䯈 t Ϣ f(α)=1–(1–α)1/3 ݇㋏
೒8
60
40
1423
1373
1323
1273
1223
20
0
2
4
K
K
K
K
K
6
1200
1000
800
600
400
200
0
10
8
Time/h
Relationship between α, reaction temperature T and
30
50
70
90
2θ/(°)
䕀࣪⥛Ϣডᑨ⏽ᑺঞֱ⏽ᯊ䯈ⱘ݇㋏
heat preservation time t
Ti
Al
TiAl 3
TiAl
Intensity/cps
α/%
80
Fig.7
6
Fig.8 Relationship between the reaction time t and f(α)=1–(1–α)1/3
100
೒7
4
t/h
ᑨᰃᭈϾডᑨⱘ᥻ࠊ⦃㡖DŽ
0
˄10˅
೒9
Fig.9
1#䆩ḋⱘ XRD ೒䈅
XRD pattern for sample 1#
g2154g
⿔᳝䞥ሲᴤ᭭ϢᎹ⿟
k′ˈҷܹᓣ˄10˅Ёˈ԰ lnk′Ϣ 1/T ⱘ݇㋏᳆㒓བ೒ 10
᠔⼎DŽ
㄀ 38 ो
4) 䞛⫼ϔ㑻⎆-೎᳾ডᑨḌ῵ൟ᥶䅼䖬ॳᠽᬷ⊩
ࠊ໛ TiAl ড়䞥㉝ˈ⎆-೎⬠䴶࣪ᄺডᑨᰃᭈϾডᑨⱘ
⬅೒ 10 ∖ߎ ln k′ᇍ 1/T ⱘⳈ㒓᭰⥛
᥻ࠊ⦃㡖DŽ㸼㾖⌏࣪㛑Ў 76.84 kJ·mol-1
l = –9.24118ˈ
㸼㾖⌏࣪㛑Ў˖
খ㗗᭛⤂
-1
ln(k′/s-1)
Ea= –1000×l×R=76.84 kJ·mol DŽ
[1] Qu H P, Wang H M. Materials Science and Engineering[J],
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–10.6
–10.8
–11.0
–11.2
–11.4
–11.6
–11.8
[2] Liu Xiaofeng (߬ᰧዄ), He Yuehui(䌎䎗䕝), Liu Yong(߬ ੣)
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0.70
0.78
0.74
0.82
h103·(T/K)-1
al. Journal of Jinan University (Natural Edition)(⌢फ໻ᄺᄺ
᡹)[], 2005. 19(2): 106
[4] Liang Yingjiao(ṕ㣅ᬭ), Che Yinchang(䔺㤿ᯠ). Handbook of
lnk′Ϣ 1/T ⱘ݇㋏᳆㒓
Thermodynamical Data for Inorganic Substance(᮴ᴎ⠽⛁࡯
The relationship between lnk′ and 1/T
ᄺ᭄᥂᠟‫[)ݠ‬M]. Shenyang: Northeastern University Press,
೒ 10
Fig.10
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㒧䆎
Chemistry(⠽⧚ ࣪ᄺ)[M]. Shanghai: Shanghai Scientific &
1) TiO2 Ϣ Al ᣝ 1:1˄䋼䞣↨˅⏋ড়ˈ‫ܹࡴݡ‬䗖䞣
ⱘ CaH2ˈ೼ 1112~1600 K ⏽ᑺϟ㛑໳ࠊᕫ TiAl ড়䞥DŽ
Technical Press, 1998
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and γ-TiAl Alloys by Reactive Diffusion Routes(Ti/TiAl3ሖ⢊
ড়䞥ᰃϔ㑻ডᑨˈCaH2 ߚ㾷៤ Ca Ϣ H2ˈCa 䖬ॳ TiO2
໡ ড় ᴤ ᭭ Ϣ TiAl 䞥 ሲ 䯈 ࣪ ড় ⠽ ⱘ ড ᑨ ᠽ ᬷ ࠊ ໛ ᡔ ᴃ )[D].
ডᑨ䴲ᐌ䖙䗳ˈ⫳៤ TiDŽCaH2 ⱘࡴܹ䞣Ў⧚䆎䅵ㅫ䞣
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᳝ᕅડDŽ
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࡯ᄺᇐ䆎)[M]. Beijing: Metallurgy Industry Press, 2004
Discussion on Reaction Mechanism of TiAl Alloy Prepared in CaH2-TiO2-Al System
Guo Guangsi1, Hu Yan1, Cheng Yongjun2, Hu Xiaomei1
(1. Shenyang Ligong University, Shenyang 110168, China)
(2. Shenyang Aerospace Mitsubishi Motors Engine Manufacturing CO., LTD, Shenyang 110179, China)
Abstract: It is possible on thermodynamics to prepare TiAl alloy in CaH2-TiO2-Al system by Reduction-Diffusion method. It is a
first-class reaction, whose mechanism was discussed by liquid-solid contracting core model. Results show that TiO2 is reduced to Ti
rapidly, which is not the rate-controlling step of the reaction. The interfacial chemical reaction is the rate-controlling step of the reaction.
The apparent activation energy of the reduction-diffusion reaction is 76.84 kJ/mol. There is sufficient reaction when the entering quantity
of CaH2 is 1.5 times of theoretic quantity. Al powder granularity doesn’t influence the reaction. The transformation efficiency of TiAl
alloy is about 100% when the reaction temperature is 1423 K and the reaction time is 8 h.
Key words: CaH2-TiO2-Al system; TiAl alloy; reaction mechanism
Biography: Guo Guangsi, Ph. D., Professor, College of Material Science and Engineering, Shenyang Ligong University, Shenyang 110168,
P. R. China, Tel: 0086-24-24680841, E-mail: [email protected]