scholarly journals Whisker Formation in Porosity in Al Alloys

2016 ◽  
Vol 47 (6) ◽  
pp. 3459-3468 ◽  
Author(s):  
William David Griffiths ◽  
Ahmed Elsayed ◽  
Mahmoud Ahmed El-Sayed
Keyword(s):  
Author(s):  
K. Kuroda ◽  
Y. Tomokiyo ◽  
T. Kumano ◽  
T. Eguchi

The contrast in electron microscopic images of planar faults in a crystal is characterized by a phase factor , where is the reciprocal lattice vector of the operating reflection, and the lattice displacement due to the fault under consideration. Within the two-beam theory a planar fault with an integer value of is invisible, but a detectable contrast is expected when the many-beam dynamical effect is not negligibly small. A weak fringe contrast is also expected when differs slightly from an integer owing to an additional small displacement of the lattice across the fault. These faint contrasts are termed as many-beam contrasts in the former case, and as ε fringe contrasts in the latter. In the present work stacking faults in Cu-Al alloys and antiphase boundaries (APB) in CuZn, FeCo and Fe-Al alloys were observed under such conditions as mentioned above, and the results were compared with the image profiles of the faults calculated in the systematic ten-beam approximation.


Author(s):  
W. T. Donlon ◽  
J. E. Allison ◽  
S. Shinozaki

Light weight materials which possess high strength and durability are being utilized by the automotive industry to increase fuel economy. Rapidly solidified (RS) Al alloys are currently being extensively studied for this purpose. In this investigation the microstructure of an extruded Al-8Fe-2Mo alloy, produced by Pratt & Whitney Aircraft, Goverment Products Div. was examined in a JE0L 2000FX AEM. Both electropolished thin sections, and extraction replicas were examined to characterize this material. The consolidation procedure for producing this material included a 9:1 extrusion at 340°C followed by a 16:1 extrusion at 400°C, utilizing RS powders which have also been characterized utilizing electron microscopy.


1977 ◽  
Vol 38 (C7) ◽  
pp. C7-364-C7-364 ◽  
Author(s):  
D. PARIS ◽  
P. LESBATS
Keyword(s):  

1979 ◽  
Vol 40 (C2) ◽  
pp. C2-611-C2-612 ◽  
Author(s):  
K. Oki ◽  
S. Towata ◽  
M. Tamiya ◽  
T. Eguchi

2008 ◽  
Vol 45 (5) ◽  
pp. 246-250 ◽  
Author(s):  
Fernando Lasagni ◽  
Andrés Lasagni ◽  
Christian Holzapfel ◽  
Frank Mücklich
Keyword(s):  

Author(s):  
Theresa Han ◽  
Eunin Cho ◽  
Jinwoo Heo ◽  
Seoung Jae Lee

Abstract In the manufacture of Printed Wiring Boards (PWB), unwelcome structures, such as nodules and whiskers can be formed during copper electroplating with copper sulfate. Copper (Cu) whiskers with lengths of up to a few hundred micrometers can lead to electrical shorts between layers or patterns. In this paper, we document factors that can affect the growth of Cu whiskers; decomposition of additives in the Cu electroplating solution, surface stress, acidic cleaner, and the ingredients of a dry film. Contaminants from outside of the electroplating bath and the ingredients of the dry film were shown as key components in the formation of Cu whiskers.


2005 ◽  
Vol 22 (3) ◽  
pp. 321-328 ◽  
Author(s):  
Shigenari Hayashi ◽  
Brian Gleeson

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