use of metal templates for microcavity formation in alumina

Figure 3.4. Pressed samples: (a) before sintering for furnace, (b) after sintering
for furnace, (c) before sintering for dilatometer and (d) after sintering
for dilatometer ............................................................................................. 26
Figure 4.1. Relative shrinkage curves for powder compacts (UP150 MPa)
of alumina CR6, CR15, CR30F, CT3000SG and AKP50 during
sintering at a heating rate of 5 o C/min ........................................................... 28
Figure 4.2. Temperature versus time schedules of sintering tests .................................. 30
Figure 4.3. Relative density curve for powder compacts (UP 150MPa) of alumina
CR6, CR15 , CR30F, CT3000SG and AKP50 during sintering at a
heating rate of 5 o C/min ................................................................................. 30
Figure 4.4. Densification rate curve for powder compacts (UP 150MPa) of alumina
CR6, CR15 , CR30F, CT3000SG and AKP50 during sintering at a
heating rate of 5 o C/min ................................................................................. 31
Figure 4.5. Relative shrinkage curves for powder compact (UP150 MPa) of alumina
CR6 during sintering at a heating rate of 5 o C/min at 1500 o C ....................... 32
Figure 4.6. Relative density curve for powder compact (UP 150MPa) of alumina
CR6 during sintering at a heating rate of 5 o C/min at 1500 o C ....................... 32
Figure 4.7. Densification rate curve for powder compact (UP 150MPa) of alumina
CR6 during sintering at a heating rate of 5 o C/min at 1500 o C ....................... 33
Figure 4.8. SEM images of alumina powders (a) alumina CR6 (b) alumina CR15
(c) alumina CR30F (d) alumina CT3000SG (e) alumina AKP50 ................ 35
Figure 4.9. SEM micrographs of metal templates (a) Ti wire (b) Ti plate
(c) Copper wire (d) Stainless steel wire ........................................................ 36
Figure 4.10. EDS analysis of the Ti wire ........................................................................ 37
Figure 4.11. EDS analysis of the Ti plate ....................................................................... 37
Figure 4.12. EDS analysis of the stainless steel wire ..................................................... 37
Figure 4.13. EDS analysis of the copper wire ................................................................ 38
Figure 4.14. Picture of the sample after sintering. (a) Top view and (b) cross
sectional view. Notice the dark spots on the cross section that
correspond to the location of Ti wire .......................................................... 39
Figure 4.15. SEM micrographs of alumina that used Ti wire (a) alumina CR6
(b) alumina CR15 (c) alumina CR30F (d) alumina AKP50
(e) alumina CT3000SG ............................................................................... 40
Figure 4.16. Phase equilibrium diagram of Al2O3 – TiO2 system .................................. 41
ix