TY - JOUR
T1 - Creep of (Mg, Fe)O single crystals
AU - Wolfenstine, J.
AU - Kohlstedt, D. L.
PY - 1988/10
Y1 - 1988/10
N2 - The creep behaviour of (Mg, Fe)O single crystals compressed along 〈1 0 0〉 has been investigated over the temperature range 1300 to 1500° C, at stresses between 20 and 70 MPa, for oxygen partial pressures between 10-4 and 102 Pa, and with iron concentrations between 70 and 11 900 p.p.m. Under these conditions, the dependence of the steady-state strain rate on stress, temperature, oxygen partial pressure, and iron concentration can be summarized by the flow law, {Mathematical expression}exp (-445 kJ mol-1/RT. These results suggest that the steadystate strain rate is controlled by dislocation climb with a jog velocity which is limited by lattice diffusion of oxygen by a vacancy pair mechanism. The activation energy for creep, 445 kJ mol-1 is larger than that reported for self-diffusion of oxygen, 330 kJ mol-1, because the formation energy for jogs is relatively large, 115 kJ mol-1.
AB - The creep behaviour of (Mg, Fe)O single crystals compressed along 〈1 0 0〉 has been investigated over the temperature range 1300 to 1500° C, at stresses between 20 and 70 MPa, for oxygen partial pressures between 10-4 and 102 Pa, and with iron concentrations between 70 and 11 900 p.p.m. Under these conditions, the dependence of the steady-state strain rate on stress, temperature, oxygen partial pressure, and iron concentration can be summarized by the flow law, {Mathematical expression}exp (-445 kJ mol-1/RT. These results suggest that the steadystate strain rate is controlled by dislocation climb with a jog velocity which is limited by lattice diffusion of oxygen by a vacancy pair mechanism. The activation energy for creep, 445 kJ mol-1 is larger than that reported for self-diffusion of oxygen, 330 kJ mol-1, because the formation energy for jogs is relatively large, 115 kJ mol-1.
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U2 - 10.1007/BF00540494
DO - 10.1007/BF00540494
M3 - Article
AN - SCOPUS:0024091029
SN - 0022-2461
VL - 23
SP - 3550
EP - 3557
JO - Journal of Materials Science
JF - Journal of Materials Science
IS - 10
ER -