Nr 1 - ITME
Nr 1 - ITME
Nr 1 - ITME
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
SUMMARY<br />
Rola dyfuzji kationów w odkształcaniu nadplastycznym ceramik tlenkowych...<br />
THE ROLE OF CATION DIFFUSION IN SUPERPLASTIC<br />
DEFORMATION OF OXIDE CERAMICS, PART 1. ME-<br />
ASUREMENTS OF DIFFUSION COEFFICIENTS<br />
The diffusion coefficient of Hf 4+ in 3 mol % Y 2<br />
O 3<br />
stabilized tetragonal zirconia<br />
at temperatures from 1556 to 1783 K using SIMS and at temperatures 1628-1783 K<br />
using electron microprobe analyzer (EPMA) (Zr-Hf interdiffusion) in the joint<br />
between ZrO 2<br />
and ZrO 2<br />
-HfO 2<br />
composite. The Arrhenius equations obtained from<br />
SIMS measurements are<br />
⎛ − 591(<br />
following: D l = 0.50exp⎜<br />
⎝ RT<br />
⎛ 442( kJ / mol ) ⎞<br />
D gb = 0.13exp⎜<br />
−<br />
⎟<br />
⎝ RT ⎠<br />
D e Mg<br />
⎛ 445( kJ / mol ) ⎞<br />
= 0.39exp⎜<br />
−<br />
⎟<br />
⎝ RT ⎠<br />
kJ / mol )<br />
⎞<br />
⎟ (m 2 /s) for lattice diffusion and<br />
⎠<br />
(m 2 /s) for grain boundary diffusion. In the case<br />
of EPMA<br />
⎛ ⎞<br />
= ×<br />
−10<br />
360( kJ / mol )<br />
D 7.1 10 exp⎜<br />
−<br />
⎟ (m 2 /s) and ⎛ 480( kJ / mol ) ⎞<br />
l<br />
D gb = 0.37 exp⎜<br />
−<br />
⎟<br />
⎝ RT ⎠ ⎝ RT ⎠<br />
(m 2 /s). The effective diffusion coefficient of Mg 2+ for Al 2<br />
O 3<br />
and MgAl 2<br />
O 4<br />
ceramics<br />
was also determined (using EPMA):<br />
26