Vd836-2011S002009180.pdf

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Nshien cuu. Phdt triin vd Ung duns Cons nshe Vdt lieu (KC.02/06-10)- Hd Ndi 27/11/2009

NGHIEN CUtJ ANH HUONG CUA Ti02 DEN TINH CHAT

C U A G O M A 1203 S I E U M I N Ta Van Khoa \ Tran The Phirong \ Nguyln Khai Hoan², Vu Le Hoang¹

1 Vien Cong Nghe, Tong cue Cong nghiep Quoc phong. Email: [email protected]

2 Cue Khoa hoc, Cong nghe va M o i trudng, Bo Quoc phong Tom tit. Nhirng nghien cuu ve dnh hudng ciia ham luong Ti02 tdi mot sd tinh chdt cua gom Al20}

duac de cap trong bai bdo nay. Cdc thi nghiem da duac tien hanh vdi cdc mdu gdm he Al2OyCaO- Si02-MgO cd ham luong a-Al203 tic 96 - 98%, Ti02 duoc dua vao vdi ham luong tir 1 - 3% vdi vai tro phu gia ha thap nhiet do thieu ket. Ket qua cho thay cd the ha thap nhiet do thieu ket xudng 1500, 1550°C ddi vdi gdm Al203 cd 1 - 2% Ti02 ma van dam bdo ca tinh theo yeu cau sir dung.

I. Gl6l THIEU

Trong mot cong bo trudc clay, chiing toi da de cap den kha nang ha thap nhiet clo thieu kit

ciia gom A 1203 xudng dudi 1600°C khi dung phu gia T i 02 [1]. Gdm A 1203 va 1% phu gia T i 02 sau khi thieu ket d 1550°C cd cac thdng sd ve mat dd, dd xdp, dd hap thu nude vugt troi so v d i gdm khdng cd T i 02 thieu ket d cung nhiet do. D d cd the la sir k i t hop ciia ca viec tao dung dich ran ciia T i 02 v d i A 1203 lam tang he sd k h u l c h tan lan viec T i 02 lam b i l n dang mang, tang dd ldn tinh the A 1203 va dd linh ddng ciia chiing khi nung [2], [3].

De m d rdng pham v i ung dung ciia phu gia T i 02 ddi v d i gdm tien tien co sd A 1203, can nghien cuu t i m hieu nhung tuong tac giua A 1203 va T i 02 tai nhiet dd gan v d i nhiet dd thieu ket va nhung anh hudng ciia ham luong T i 02 tdi mot sd tinh chat co ly ciia vat lieu. Nhirng ket qua nghien cuu thu dugc se m d ra trien vong ve kha nang che tao trong nude vat lieu gdm tien tien nen oxit nhdm sir dung trong cac linh vuc dac biet nhu lam vat lieu chdng dan.

II. THUC NGHIEM

Nguyen lieu dugc sir dung de nghien cuu la bdt oxit nhdm a-Al203 mac B2M-07D ciia

hang Keifeng Special Refractories v d i cac thdng sd: dang thu hinh a (corudum), do sach A 1203 = 99,98%, kich thudc hat trung binh 0,15 pm, ty trong 3,94 g/cm³. Hon hop bdt gdm A 1203, cac phu gia S i 02, M g O , CaO va T i 02 v d i cac phuong an thanh phan nhu trong bang 1.

Bdt dugc nghien trdn trong may l i tam hanh tinh trong 4h v d i t i le bi/bdt la 2/1. Sau dd bdt dugc tam chat ket dinh P V A , ep thanh cac mau dudi ap suat l T / c m², thieu ket 0 cac nhiet do 1500, 1550°C trong vong l h .

Bang 1. Thanh phan phdi lieu.

T T K i hieu mau

Nguyen lieu chinh a - A l203, %

Ham luong phu gia, % T T K i hieu mau

Nguyen lieu chinh a - A l203, %

T i 02 HH3 ( S i 02+ C a O + M g O )

1 A T I 98,0 1,0 1,0

2 A T 1.5 97,5 1,5 1,0

3 A T 2 97,0 2,0 1,0

4 AT2.5 96,5 2,5 1,0

5 A T 3 96,0 3,0 1,0

Cac mau gdm sau khi che tao da dugc kiem tra dd cirng Vicker H v i0 theo tieu chuan A S T M C 1327 - 03, do b i n udn dugc do bang phuong phap 4 d i l m theo tieu chuan A S T M C 1 1 6 1 - 02c, he sd chdng nirt K iC dugc xac dinh theo phuong phap v i t dam Vicker. Do hap thu

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Nshien ciru. Phdt men vd Cns dims Cons nshe Vdt lieu (KC.02/06-10>- Ha \'ni ?7/l 1/2009

nuac. mat do khoi. khoi lugng rieng va do xdp ciia cac mau duoc xac dinh theo tieu chuan A S T M C 373 - 88 (Reapproved 1999).

DT. K E T Q U A V A T H A O L U A N

Kha nang kit khdi cua gdm AI2O3 khi thieu ket the hien qua cac thong so ly tinh nhu: khoi

lugns riens. mat do kh6i. do xdp va do hap thu nuac. T u cac ket qua do dugc dua ra trong bans":, co the t h l y d 1550°C, cac mau A T I ket khoi tot nhat v d i khdi lugng rieng va mat dp khdi cao nhat Cac gia tri nay giam d i n khi tang ham lugng T i O ; . Cung v d i su giam dan m | t do la su tang do xdp va do h i p thu nude, t h i p n h i t la A T I den A T 2 t i n g nhe. tir A T 2 den AT3 cac sia'tri nay g i n nhu khdng thay ddi. K h i ha nhiet do thieu ket xudng 1500°C. cac gia tri nay cd su thay'ddi khac biet theo ham lugng T i O ; . Luc nay cac m l u ket khdi tdt nhat la A T 2 vdi khdi luong rieng va mat do khdi cao nhit. do xdp va dd h i p thu nude thap nhat. con cac mau ket khdi kem nhat lai la A T I .

Mat do tuong ddi y ciia cac m i u cung b i i n thien theo khdi lugng rieng va mat dd k h d i . 0 nhiet do thieu k i t 1550°C cac mau A T I ( 1 % T i 02) cd y cao nhit, con d nhiet do 1500°C cac mau A T 2 (2% T i O:) cd y cue dai. N d i chung, cac m i u thieu ket deu dat mat do tuong ddi tren 0.955 (95.5%) va cac mau cd 1% T i 02 dat y cao n h i t la 0.9743 k h i thieu k i t d 1550°C.

K h i thieu k i t d 1550°C cac mau cd mat dd tuong ddi cao han k h i thieu ket d 1500°C. M d i quan he giua cac tinh chit tren ciia gdm v d i ham lugng phu gia T i O: d cac nhiet do thieu ket dugc the hien tren hinh 1.

Ca tfnh ciia gdm k i t c i u ca sd oxit nhdm dugc dac trung bdi 3 dai lugng chinh la dd ben udn^(CTU). do cung Vicker (Hv) va he sd chdng nut Kic (gdm oxit nhdm cd ca tinh tdng hpp tot phai dam bao dugc cac yeu td tren theo yeu cau sir dung lam vat lieu chdng dan). Cd the thay su tuong ddng giua ly tinh va co tinh ciia vat lieu. Cac thdng sd ve mat do. dd xdp, dd hap thu nude t h i hien kha nang k i t khdi va cd anh hudng den ca dnh. Ket qua do ca tinh cac mau gdm dugc neu trong bang 3 va hinh 2 cd the thay ca tinh tdng hap tdt tuang ung v d i kha nang k i t khdi cao ciia cac m i u sau k h i thieu ket. Do ben udn. dd cirng va he sd Kic deu tang khi tang ham lugng T i 02 tir 1 den 2% d nhiet do thieu ket 1500°C.

Bdng 2 Khdi lucmg rieng. mat dp khdi, dp xop vd dp hdp thu nude ciia cdc mdu gdm AI2O3 v&i phu gia TiO:.

TT M a u va che dd thieu ket

Mat dd khdi.

s'em"'

K h d i lugng riens. s/cm"

D d xdp bieu kien. %

Dd hap thu nude. % TX: 1 5 0 0 ° C : x±: l h

1 A T I ( 1 % T i C V 3.7656 3.77:4 0.1813 0.0482

2 A T I . 5 ( 1 . 5 % TiO:> 3.7764 3.7861 0.1667 0.0436

A T 2 (2% T i O;) 3.7990 3.8045 0.1454 0.0383

4 A T I 5 ( 1 5 % T i O . i 3.7845 3 . 7 9 1 : 0.1534 0.0405

5 AT3 (3% T i 02) 3,7764 3.78:5 0.16:3 0.0430

T,k:1550^oC;t*: l h

6 A T I ( 1 % T i O i ) 3.8:50 3.8:96 0 . i : o : 0.0314

7 A T I . 5 ( 1 , 5 % T i 02) 3.8190 3.8:44 0.13:6 0.0323

8 A T : (.:% T i 02) 3.8163 3.8:14 0.1338 0.0351

9 AT2.5(2.5% T i O:i 3,8026 3.8083 0,1337 0 . 0 3 5 :

10 A T 3 (3% TiO-) 3.794: 3,7993 0.1338 0.0353

Cac mau cd ca tinh tdt nhat la A T : v d i 2% T i O ; . O nhiet dd thieu ket cao hon la 1550^CC dd cirng va he sd Kic van tang theo ham luong T i O: tir 1 den 2% . dd ben udn cao n h i t vdi ham lugng 1 % T i O :^va giam nhe den 2% T i 02.

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Nshien cim. Phdt trien vdCns dung Cnne nshe Vdt lieu (KC.02/06-10)- Hd Ndi 27/11/2009

K h i ham lugng T i 02 Ion hon 2% lugng pha tialite A l2T i 05 sinh ra n h i l u hon. Pha nay co tac dung thuc day ket khdi nhung can han che so lugng do lam no hat manh va co anh huong xau d i n co tinh [5], [6], [7]. Co le vay ma cac mau AT2.5 va A T 3 co co tfnh kem hon cac m l u A T I va A T 2 . N o i chung, cac mau gom v o i 1 - 2% T i 02 co co tinh dam bao yeu cau lam giap chong dan (Hv > lOGPa, Kic ^ 3 MPa.m ' ya ou > 250 MPa) [4]. Dieu nay cho thay co t h i su dung t6i da 2% T i 02 lam phu gia thieu ket va co the ha thap nhiet do thieu ket gom A 1203 xudng den 1500°C.

Bang 3. Cdc ddc trung ca tinh ciia cdc mdu gom AI2O3 vai phu gia Ti02. T T Mau va che do thieu ket Do ben uon

tfu, MPa

Do cung H v1 0, GPa

He sd chong nut Kic, M P a . m^{1 7 2} Tthieukit" 1500°C; Tthieukat" l h

1 A T I ( l % T i 02) 247 10,60 3,32

2 A T I . 5 ( l , 5 % T i 02) 252 11,11 3,49

3 A T 2 (2% T i 02) 255 12,02 3,65

4 AT2.5 (2,5% T i 02) 237 12,02 2,94

5 A T 3 (3% T i 02) 231 12,03 2,43

Tthieuk^: 1550°C; tthieukit: l h

6 A T I ( l % T i 02) 253 11,16 3,46

7 A T I . 5 ( l , 5 % T i 02) 250 11,50 3,55

8 A T 2 (2% T i 02) 249 12,10 3,67

9 AT2.5 (2,5% T i 02) 228 12,14 3,08

10 A T 3 (3% T i 02) 215 12,19 2,89

3.84

= 3.82 M :i 3.80

Im DO

= - 3.78 US

3.76

• Mat do khoi | j^{3 M}

• Khiil luong rieng

3.78 3.76 1.0 1.5 2.0 2.5

Hain luong TiO,, % 3.0 Hinh 1. Mdi quan he giua khdi lucmg

rieng, mat dp khdi, dp xdp, dp hdp thu nuac vd mat dp tuong ddi cua

gdm vai ham luong T1O2.

0.20 0.16 3.82 - £

s .

= 0.12 - a :S 3.80 '^:o -

-z 'C -fi '2

~ 0.08

* a 0.04

0.00

0.380 0.975 0.970

§ 0.965

•o-

=. 0.960 0.955 0.950

•1500"

•1550°

Dp bap thu nuoc

1.0 1.5 2.0 2.5 Haui luong TiO, % 3.0

1.0 1.5 20 2J Ham luong TiO , % 3.0

0.20 0.16 0.12 0.08 0.04 0.00

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Vd:hi.. KC.C: 05-

Cdc mau thieu kit a 15Q(r C:

Trer. hiri- 5 l i arm FeSEM cua cac mau A T I va A T 2 sau khi thieu ket a 1500°C. Co the khc>£ ; : su k h i ; ri-.au r ± i i u '• e lech ± u v c va hiruh cung ha; o ;a 2 m i u P h i n icr. cu;

hat co kich thudc khoani: 3 - 5 urn. xen lan mot so it cac hat cd kich thudc ldn hem khoang - 10 urn va mot so hat nhd cd l u m . Hinh dang hat da dang gom ca nhung hat tuong doi ddng d l u 3 kich thudc lan nhuns hat co 1 kich thudc ldn hem nhieu so v d i 2 kich thudc con lai (hat i i : co do: i i ma: cua rmi-. nghuen rdr. ;c hoc r : : ; do. C i ; mau A T 2 ;c xu hudng keo diu ca; ha: hem so vdi ; i ; mau A T I d nhiet do thieu ket nay.

' 12-5

U 1.5 ZJB ax Hhm Itro-ns TiO.. °*

Hinh 3. Anh FeSEM cdc mau ATI s, \ JAT2 r J= :h:iu ki: ? IflC'C.

Cdc mdu rhieu ket a 155& C:

6 urue: do thieu ket cao hon t l 5 5 0^:C da may su k h i ; nhau ve kich t h u d ; hat ciia cac mau A T I hmh - u v i : i o m l u A T 2 hmh -b Su r.d ha: d m l u A T 2 men ra r.har.h huu i i ;

% di m l u A T I i d h i m lucmg T : 0: ;ao horn. Kau he: ; i ; hai ;ua A T 2 ;o kich thudc khoar.£ 10

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Nshien cim. Phdt trien va tins duns Cons nshe Vdt lieu (KC.02/06-10)- Ha Noi 27/11/2009

- 12 p.m, trong khi ATI chi co mot so hat co kich thuoc nay con lai chu yeu la cac hat co kich

thuoc co 5—7 p m va cac hat nhd hon co 2 - 3 p m . V i vay nen thieu ket cac mau co 2% T i O : d nhiet do thap hon 1550°C.

Hinh 4. Anh FeSEM cdc mdu ATI (a) va ATI (h) da thieu kk d 155CCC.

I V . K E T L U A N

- Dung phu^gia Ti02 da ha thip duoc nhiet do thieu kit g6m A1203 xudng 1550°C va

1500°C. Cac mau su dung tu 1 - 2% T i 02 d l u dap ung yeu c i u co tinh cua g6m lam giap chdng dan (Hv = 10,60 - 12,19GPa, Kr c = 3,32 - 3,67 M P a . m^{1 7 2} va Gu = 247 - 255MPa), do x6p va do h i p thu nude t h i p (P = 0,12 - 0,18%; A = 0,031 - 0,048%), mat do tuong ddi dat 9 5 , 9 - 9 7 , 4 % .

- Ham luong phu gia T i 02 cd t h i su dung tdi da cho gdm A 1203 la 2% v i k h i dung ham luong T i 02 t d i 3% thi dd ben udn va he sd chdng nut cua gdm giam dang k l . Neu dung 1%

T i 02 nen thieu k i t d 1550°C d l dam bao mat do va co tfnh, n l u diing 2% T i 02 nen thieu k i t d 1500°C d l hat khdng nd qua ldn. K h i sir dung phu gia T i 02 thi khdng nen thieu k i t gdm d tren 1550°C v i d nhiet do cao hon T i 02 lam giam manh co tinh vat lieu.

Loi cam on

Cong trinh nay duoc sir tai tro ciia dl tai cip nha nude ma sd KC.02.26/06-10 Tai lieu tham khao

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Poluboiarinov, R. Popilskyi. Keramika iz vysokoognheipornyx okislov. Moskva

"Metallurgia"(1977).

2. Nguyln Dang Hiing. Cong nghe san xuit vat lieu chiu lua. Nha xuit ban Bach Khoa - Ha N d i , (2006).

3. V u Le Hoang, Tran The Phuong. Tap chi Khoa hoc Cong nghe K i m loai, Sd 2 1 , thang 12/(2008).

4. Eugene Mevedovski. Alumina Ceramics for Ballistic Protection, Part 1 - 2. American Ceramic Society Bulletin, V o l 8 1 , N² 3 - 4, March (2002).

5. S. M . Lang, C. L . Fillmore and L . H . M a x w e l l . Journal of Research of the National Bureau o f Standards, V o l 48, N² 4, A p r i l (1952).

6. M . Mann, G. E. Shter, G. S. Grader. J. Mater. Res., V o l 17, N² 4, A p r i l (2002).

7. M . Mann, G. E. Shter, G. S. Grader. Journal of Materials Science 37 4049-4055 (2002).

8. Wenming Zeng, Lian Gao, L i n h u a G u i , Jinkun Guo. Ceramics International 25 723-726 (1999).