on G TiC-Ni

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on G TiC-Ni

₃

Al Cermet

Ji Heon Kim and Wan Jae Lee

Department of Metallurgy and Materials Science Engineering Hanyang University Ansan, 425-791, Korea (Received 24 September 2002 ; Accepted form 16 October 2002)

Abstract The effects of boron or manganese added as B₄C, Mn, TiB₂, B on TiC-30vol.%Ni₃Al cermet sintered at 1380 and 1400^oC for 1 hour, were examined in relation with shrinkage, relative density, microstructure, lattice parameter, hardness and fracture toughness (K_IC). The results are summarized as follows: 1) The highest shrinkage showed about 30.5% in the specimen added B₄C and the maximum relative density was about 99% in the specimen added TiB₂; 2) The grains of TiC were grown during sintering and made the surrounding structure by adding boron and manganese. The largest grain size showed about 2.8µm in the specimen with boron sintered at 1400^oC; 3) The lattice parameter of TiC was about 4.325Å and Ni₃Al about 3.592Å by adding other elements; 4) The highest hardness was about 1100 kgf/mm² in the specimen with B4C; 5) The fracture toughness (K_IC) showed about 15 MNm^-3/2 in the specimen added TiB₂.

Keywords : Cermet, Ni₃Al, TiB₂, Microstructure, Hardness.

1. B

TiCê WCê .ã.ö j~ .ÓW"

ÚÖzWf Ö>~æò .K" W ÔjB "

.Ó Ïb ;>Ú ÒÏ> ®j ö, Ú îÎÒò ~ æ ª¢ö ÒÏ>æ á~º 6j B F~¶ Öç Ni 6º Ni-Co¢ &Ú bî

B NÒò Ni3Al .³*zb &Ë ©b

6>î. &¶ f TiC-Ni3Al ~ Öç ï,

²Ö Nêf *, Ò ê² 5 Mo2C Î& ö

& ¢ >¯~, Ûç~ ç ²Ö ~&

²ÖÚ¢ B > ®b, ßWê V~ TiC- Niêf FÒ Ö"¢ áî^1,2).

Ni₃Al .³*zbf L12 Ö; ;ê&

800^oCræ Nê ~Wb Ã&~, NöB Ú ÖzW, ÚãW, ÚÏÏW Ö>~, Wf

«; ö² Bj, ~~; ö² Mnj ²ï Î&

~ BFB rJ^ ®^3,4).

öBº TiC-Ni3Al ~ W" Wj BF Ï'b »²(B)¢ '' ; TiB2, B₄C, Bf *(Mn)j ²ï Î&~ .~ ^

ç" Vê' ßWö ~º 'Ëj Ò~&.

2. þ O»

öòªöº TiC(Herman Stark Co., «ê £ 1.4 µm), Ni₃Al(X-form Co., 44µm ~), B4C(Herman Stark Co., 1.5µm), TiB2(Herman Stark Co., 1.5~

2.5µm), B(Herman Stark Co., 4~8µm), Mn(Kanto Chem. Co. £ 2µm) ªöj ÒÏ~, TiC-30vol.%- Ni₃Al~ ¢; Wb ~ Ni3Al ïö &~

0.3 wt%~ B4C, TiB₂, B 5 7.5wt%Mnj Î&~

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V~&. Fig. 1f *Ú þ";j BÛ'b

~&.

' W~ ªöj FW"&V(Planetary Mill)öB 10* ÿn Û"&j ê ê J6öB

~&. B ªöj 100 MPa~ {Kb W;~

, £ 5Ü10^-2Torr~ ê 7öB 1380^oCf 1400

oCöB 1* ÿn ²Ö~&. ' W~ ²Ö Úö &~ ' >»" &ê(ASTM B 328)¢

G;~&. ' ²ÖÚ~ ^çf jÒ F

" ¾ÊÞ î ê FE-SEM(JEOL Co. JSM- 6330F)j ÒÏ~ &V~&. Ò TiC «¶V º Image Analyzer¢ ÒÏ~ ~&. 6, XRD(Philips Co. PW1730) ç 7ö îÚ ç

~ Â*¦f TiCf Ni3Al~ Ï¶;>¢ G;~&

. Vê' Wîº jÊãê¢ ~7 50 kgb

G;~&b, Wf Palmqvist Toughness Test O

»⁵⁾b ãê {z F~ crack ^¢ G;~

2ZW(KIC)j ~&.

3. þÖ" 5 V

ÖF Fig. 2ö TiC-30vol.%Ni3Alö æWª(B4C, Mn, TiB₂, B)j Î& ²ÖÚ >»" ç&&êf

~ &ê¢ ¾æÚî. Fig. 2öº jv¢ *~ æ Wªj Î&~æ pf Þ~ Ö"ê ÷V~&. ¢

>'b >»f æWª Î&>æ pf Þö Bº 1380^oCöB £ 27.6%, 1400^oCöB 29.6%

²ÖNê& ¸b çß~&. ¾ B4C, Mn, TiB₂, Bj ²ï Î& ãÖöº ²ÖNê~ Nö

~ >»~ Nº Ö 'îb, '' £ 31,

29.8, 29.3, 27% 7öB B4C¢ Î& ãÖ

&Ë ¸² ¾æÒ. ²ÖÚ~ ç&&êº Mnj Î

& ãÖö jv' Ô² ¾æÒb, TiB2¢ Î&

ãÖö &Ë ¸² ¾æÒ. &Ë ¸f ç&&ê¢

¾æÚº ©f TiB2¢ Î&~ 1380^oCöB ²Ö

ãÖö £ 99% ¾æÒ. TiB2¢ Î&~&j r Î&~æ pf Þ ç&&ê& ¸jæº ©j r > ®î.

rb æWª Î&ö V .~ SEMö ~

^çj Fig. 3ö ²ÖNêf~ &ê ¾æÚî . æWª Î&>Úê TiC «¶º ;ç ';b

·f «¶f «¶ b>Ú ®b, «

¶~ ãÖº ²Ö 7ö WË~ «¶ 7¦f

¦öB «z~ N ¾æÒ. *çf Mn j Î& ãÖö z× F«~² ¾æÒ. ÿ¢ W~ .öBº ²ÖNê~ Nö ~ ^ç ç~ æzº «{® ª>æ p~.

Fig. 3~ ^çöB Image Analyzerf Fullman

~ ⁶⁾j ÒÏ~ TiC «¶~ ï V¢ G;

Ö"¢ Fig. 4ö ~&. TiC «¶~ ï V º æWªj Î&~æ pf .(â 7 Free)"

B₄C, Mn, TiB₂, B¢ Î& .~ ãÖö 1380^oC

²ÖöB '' £ 1.2, 1.65, 1.9, 1.85, 1.6µmb

MnÎ& .öB & ¾æÒ, 1400^oC ²Öö Bº '' £ 1.58, 2.1, 2.4, 2.5, 2.8µmb BÎ

& .öB & ¾æÒ. ÿ¢ ²ÖNêöB æ Wª Î&>æ pf .ö j~ æWª Î&

Fig. 1. Flow chart of experimental procedure.

Fig. 2. Relative density and shrinkage of TiC-30vol.%- Ni₃Al cermets in relation with other components and sin- tering temperature.

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Fig. 3. SEM microstructures of TiC-30vol.%Ni₃Al cermets in relation with other components and sintering temperature.

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> TiC «¶~ ï V& Ã&~&. 6 ÿ

¢ . WöBº ²ÖNê& ¸b «¶WË

¢Ú¾ ï TiC «¶~ Vº Ã&~&. ¢>' b TiC-Mo2C-Ni öB~ «¶WËf ²Ö 7 ö TiC«¶ "*ö "æç(surrounding structure) j ;W~B ¢ÚÂ. TiC-Ni3Al öBê æW ª Î&öB "æç &V> ®bæ «¶W Ë Vº TiC-Mo2C-Ni ~ ãÖf ÿ¢ © b ÒòB. ¯, æWª Î&ö ~~ ç Â*

Nê~ æz, ç" TiC «¶ êöB~ CÂ V

f çöB~ {Ö ³ê TiC «¶~ Ï- CÂö ~ Ostwald WËö 'Ëj V r^

¢ 'B. »²& FB B4C, TiB₂, B& Î&

B .~ ãÖöº ²Ö ç Â* Nê& Ô~

V r^¢ ºGB. º ²Ö ßN ";öB Î& bî 7ö Bö¶& {Öö ~~ Ni3Al

«¶ öB Ni" B ö¶& Ö> Ni-B ç ê⁷⁾öB r > ®º :f ? ç jv' Ôf NêöB W>B Ni3Al «¶~ Ï& Ô f NêöB ¢ÚÒV r^¢ 'B. 6

Mn Î&~ ãÖê çVf FÒ~² Ni-Mn çê⁷⁾ öB Ni 7ö Mn Ã&> [6 Ôjææ, Mn ê Ni3Al~ ÏNê¢ ÔºV r^¢ ' B. Ò Î& Wª ç 7ö Ï>Ú

®b TiC «¶~ Ostwald WËö ÚÊ ;

&®j ©b Òò> ;ï' ï&º Ö Ú [. 1400^oCöB TiB2f B Î&ö ~~ TiC «

¶ WË 1380^oCö j~ *&~² Ã& ©f

ç" TiC «¶ êöB ç 7ö Ï>Ú ®º Ti, C, B ö¶~ zK" ç 7~ {Ö ³ê&

Ã&®V r^¢ 'B.

rb æWª Î& ²Ö 7ö B2ç~ Â*

¦¢ Ò~V *~ Cu Kαö ~ X-F ².

þ Ö"¢ Fig. 5ö ~&. ' ²ÖNêöB

².NZf æWªj Î& .¾ Î&~æ p f .(â 7 Free)öB ÿ¢~² ¾æÒ. V¢

B .ö Î& æWªf ²Ö 7ö TiC¾ Ni3Al 7ö *¦ Ï>î 6B.

Fig. 6ö æWª Î&ö ~ TiCf Ni3Al~ Ï¶

;>¢ ~ ~&. Fig. 6(a)öB TiC~ Ï Fig. 4. TiC particle size of TiC-30vol.%Ni₃Al cermets in

relation with other components and sintering tempera- ture.

Fig. 5. X-ray diffraction patterns of TiC-30vol.%Ni₃Al cermets in relation with other components and sintering temperature. (a) sintering at 1380^oC and (b) sintering at 1400^oC.

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¶;>º 1380^oC ²Ö~ ãÖ æWª Î&~æ pf

.~ ãÖ £ 4.334ÅöB æWª B4C, Mn, TiB₂, B Î&> £ 4.327çb Ôjr. ¾ 1400^oC ²Ö~ ãÖº Î&~æ pf .~ ãÖ

£ 4.318çöB B4C Î&~ ãÖº £ 4.320çb

£* Ã&>, Mn, TiB2, B Î&~ ãÖº £ 4.325çb ~ FÒ~&. VB æWª Î&

>æ pf .öB TiC~ Ï¶;>& ²ÖNê æ zö ~~ N¢ ¾æÚ ®. ¢>'b

TiC~ Ï¶;>º Ï¶ 7~ ê²ö¶~ ê" î êö ~~ æz. 1380^oC ²Ö~ ãÖº TiC

«¶ 7~ ê²ö¶& Ni3Al Öçb {Ö ' îV r^, 1400^oC ²Ö~ ãÖº {Ö ¢Ú

¾ îê >ÚB Ï¶;>~ æz& ¢ÚÒ 'B. æWª Î& ãÖö TiC~ Ï¶;>& ² ÖNêf ç&ì ~ ¢;~² ¾æÂ ©f, Î&

ËçÎ ~ ®³⁾. V¢B B& FB Wªf Ni3Al~ Ï¶;> æzö ² V~æ á

~&V r^ö ~ ¢;~² ¾æÒ 'B.

¾ Mn Î&~ ãÖº ²ÖNê 1380^oCöB £ 3.597ç, 1400^oCöB £ 3.578çb N¢

®. Mn Ni3Al Öçö ~~;b Ï

>æ, L12 Ö; Ni3Alf ö Niö¶&, Sæ6ö Alö¶& *~~ ®ÚB, Mnö¶& ÚÊ ö¶f~ ~~ &ËWf ö¶ Vf &ê ®j ©

. ö¶>ãf Mn, Ni, Al '' 1.37, 1.25, 1.43çæ, Ni3Al~ Ï¶;>º Mn Ni" ~~

> Ã&~ Al" ~~~ 6² ©b 6B . V¢B Ni3Al~ Ï¶;>& 1380^oC ²ÖöB Ã

& ©f Mn Ni" ~~>, 1400^oC ²ÖöB 6² ©f Mn Al" ~~~&V r^¢

'B. ¾ 1380^oCöB Mn Ni" ~~ ¦º 6~V ÚJÖ .êö Ò¦Æ¢ º.

rö Vê' Wî TiC-30vol.%Ni3Al ~

ãêö ~º æWª Î& 5 ²ÖNêf~ &ê

Fig. 7ö ~&. .~ ãêº 1400^oC ²Ö~

ãÖ æWª Î&~æ pf ., B4C, Mn, TiB₂, B Î&.öB '' £ 985, 1103, 1080, 1070, 1095 kgf/mm²b æWª Î&~ ãÖö ¸² ¾æ Òb, ß® B4C Î&~ ãÖ& 8j ¾æî . 1380^oC ²Ö~ ãÖº ãËf FÒ~¾ £* Ô

² ¾æÒ, Mn" TiB2 Î&¢ B~ ²ÖNê Nö V ãê~ Nº ~ ìî. Mn"

TiB₂~ ãÖº Mn" Ti Ni3Al 7~ Al" ~~~

Ï>Ú ;z>îV r^ö ²ÖNê& ¸j>

Ïï Ã&~ ãê& ¸jr 'B.

. ãê& B4Cf B¢ Î& ãÖö jv' ¸²

relation with other components and sintering tempera- ture. (a) TiC lattice parameter and (b) Ni₃Al lattice para- meter.

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B.

TiC-30vol.%Ni₃Al ~ 2ZW(KIC)j Palmqvist Toughness Test O»⁵⁾b ãêG; ê {z F~

crack ^¢ G;~ r b 2ZWj ~

&.

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VB, Aº ç>(0.0028), Hº ãê(N/mm²), P º ~7(N), Σlf ãê {z F~ ¿^~ (mm).

Fig. 8ö TiC-30vol.%Ni3Al ö æWª Î&f

2ZW(KIC)"~ &ê¢ ¾æÚî. ¢>'b

î. ~ W8f TiB2¢ Î& ãÖö ²ÖN êö ç&ì KIC 8 14~15 MNm^-3/2& áÚr.

Bf Ni3Al~ Wj ËçÊæ B FB TiB2

º TiCf Ni3Al~ ê~ Öj ;z~ ~

*2¢ ÛB~&V r^ö 2ZW ¸² ¾æÒ 'B.

4. Ö

TiC-30vol.%Ni₃Alö æWªb B4C, Mn, TiB₂, Bj ²ï Î&~ 'Ëj ²ÖNêf~ &ê

Ò~ r" ?f Ö"¢ áî.

1. ²ÖÚ~ ' >»f B4C¢ Î&~

1380^oCöB ²Ö®j r £ 30.5% &Ë ¸~b, ç&&êº TiB2¢ Î&~ 1380^oC ²Ö~&j r £ 99% &Ë ¸² ¾æÒ.

2. ^çöB TiC «¶º ';, ²Ö 7ö

«¶WË ¢Ú¾B «¶"*f 7¦º «z~ N

& ¾æÒ. «¶WËf ²ÖNê& ¸b z×

«{® &V>îb, TiC~ ï«êº 1400^oC ² Ö~ ãÖ æWªj Î&~æ pf ãÖ,

B₄C, Mn, TiB₂, B Î&BB '' £ 1.58, 2.1, 2.4, 2.5, 2.8µmb B Î&~ ãÖ& &Ë

&~&.

3. æWª Î&ö ~ ççö B2ç~ Âf

&V>æ p~b, XRD ².NZöBê TiCf Ni₃Al ç~ ².bò ¾æÒ. æWª Î&ö ~

TiC~ Ï¶;>º 1400^oCöB £ 4.325çb

FÒ~&b, Ni3Al~ Ï¶;>ê Mn Î&~ ãÖ

¢ B~ £ 3.592ç FÒ~&.

4. ãêº B4C¢ Î&~ 1400^oCöB ²Ö~&j ãÖö & £ 1100 kgf/mm²& áÚr.

5. 2ZW(KIC)f Mnj B æWª Î&

Ëç>îb, ~ Wf TiB2¢ Î& ãÖö

²ÖNêö ç&ì £ 14~15 MNm^-3/2& áÚr.

^^ò

1.¶^", jÒ: ªö¢.²æ, 5 (1998) 286.

K_pj A H P Σl ---

=

Fig. 7. Vickers hardness of TiC-30vol.%Ni₃Al cermets in relation with other components and sintering tempera- ture.

Fig. 8. Toughness values of TiC-30vol.%Ni₃Al cermets in relation with other components and sintering temperature.

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