TY - JOUR
T1 - Effect of intermetallic diffusion between Pd and Ti-Al alloy on the performance of Pd/Ti-Al alloy composite membranes
AU - Zhang, Dongqiang
AU - Fan, Yiqun
AU - Xu, Nanping
AU - He, Yuehui
PY - 2011/7/15
Y1 - 2011/7/15
N2 - The Ti-Al alloy possesses very desirable properties such as having a low density, high specific strength, good oxidation resistance at high temperatures, good acid or alkali resistance, and easy to process. Therefore, the use of porous Ti-Al alloys for the support of palladium composite membranes is an attractive alternative compared to stainless steel and ceramics. However, information on the intermetallic diffusion between Pd and the Ti-Al alloy at high temperatures is not yet available. In this work, the intermetallic diffusion between Pd and the Ti-Al alloy at high temperatures was studied using backscattered electron microscopy (BSE), EDX cross-sectional line scans, and electron probe microanalysis (EPMA). The results showed that neither diffusion of palladium nor diffusion of titanium and aluminum was observed after 40. h of treatment at 500 °C in hydrogen, which proved that the Ti-Al alloy effectively avoided the diffusion of metals compared to stainless steel. However, extensive intermetallic diffusion occurred between the Pd and the Ti-Al alloy after 40. h of treatment at 700 °C in hydrogen. Ti and Al atoms diffused from the metal-support interface into the Pd membrane layer. Pd also diffused into the Ti-Al alloy support. Significantly, the flux decline and the formation of pinholes on membrane surface correlated to the degree of intermetallic diffusion, and intermetallic diffusion would intensify leak formation.
AB - The Ti-Al alloy possesses very desirable properties such as having a low density, high specific strength, good oxidation resistance at high temperatures, good acid or alkali resistance, and easy to process. Therefore, the use of porous Ti-Al alloys for the support of palladium composite membranes is an attractive alternative compared to stainless steel and ceramics. However, information on the intermetallic diffusion between Pd and the Ti-Al alloy at high temperatures is not yet available. In this work, the intermetallic diffusion between Pd and the Ti-Al alloy at high temperatures was studied using backscattered electron microscopy (BSE), EDX cross-sectional line scans, and electron probe microanalysis (EPMA). The results showed that neither diffusion of palladium nor diffusion of titanium and aluminum was observed after 40. h of treatment at 500 °C in hydrogen, which proved that the Ti-Al alloy effectively avoided the diffusion of metals compared to stainless steel. However, extensive intermetallic diffusion occurred between the Pd and the Ti-Al alloy after 40. h of treatment at 700 °C in hydrogen. Ti and Al atoms diffused from the metal-support interface into the Pd membrane layer. Pd also diffused into the Ti-Al alloy support. Significantly, the flux decline and the formation of pinholes on membrane surface correlated to the degree of intermetallic diffusion, and intermetallic diffusion would intensify leak formation.
KW - Intermetallic diffusion
KW - Leaks
KW - Palladium membrane
KW - Ti-Al alloys
UR - http://www.scopus.com/inward/record.url?scp=79958044625&partnerID=8YFLogxK
U2 - 10.1016/j.memsci.2011.04.052
DO - 10.1016/j.memsci.2011.04.052
M3 - 文章
AN - SCOPUS:79958044625
SN - 0376-7388
VL - 377
SP - 221
EP - 230
JO - Journal of Membrane Science
JF - Journal of Membrane Science
IS - 1-2
ER -