Cracks are only active when they first form and have a critical gap
width. As they grow wider, they cease to become active and release D2
from the material, which reduces the activity of those gaps that
remain active. The paper your cite was written before the critical gap
size was understood and describes only the negative effect of cracks.
Pd turns out to be a very poor choice of material because it forms
gaps too easily and these gaps quickly grow too wide. This effect can
be reduced by introducing certain impurities and using special
treatments. However, because these treatments were not related to
their effect on producing gaps, the understanding has not developed.
Ed Storms
On May 15, 2013, at 8:11 PM, Axil Axil wrote:
Jed stated:
http://home.netcom.com/~storms2/review4.html
Formation of b-PdD Containing High Deuterium
Concentration Using Electrolysis of Heavy-Water
This paper will present evidence for a different model based on
almost complete hydrogen transport through the surface, diffusion
within the bulk material, and eventual loss through a crack structure.
A crack structure is produced within metals when they react with
hydrogen. This structure is caused by increased brittleness and by
physical expansion as the hydride is formed.
The limiting composition of b-PdD obtained during electrolytic
loading results from a complex competition between diffusion of D
atoms through any surface barrier, diffusion within the bulk sample,
and loss of deuterium gas from surface-penetrating cracks.
Reductions in surface-crack concentration and surface-barriers are
essential steps to achieve high compositions.
Axil replies:
The irony here is that cracks are the causative factor in the
reaction and not the limiting factor. The more cracks that are
generated by loading, the better things get.
The more that the palladium suffered from cracks, the better it
performed in the LENR experiments.
On Wed, May 15, 2013 at 8:07 PM, Jed Rothwell
<jedrothw...@gmail.com> wrote:
I wrote:
When a cathode fails in a properly equipped lab, they always know
why it failed. They can spot the defect.
Knowing why and how something fails does not mean you know how to
prevent the failure. Rockets often explode. The telemetry usually
tell investigators why it exploded. They try to fix that problem but
they do not always succeed, and there are an unknown number of
undiscovered problems left over.
Rockets are very complicated systems, which operate at the extreme
limits of temperature and pressure. A Pd metal lattice undergoing
electrolysis is also an immensely complicated system, and it is
operating at far higher pressures than any rocket or other
mechanical system, albeit in a microscopic domain. It would not
surprise me if it takes as much money and effort to tame the metal
lattice as it took to make rockets reliable enough for commercial
applications and ICBMs. A cold fusion cathode is small and
featureless but that has no bearing on how complicated it is. It may
turn out to be more complex than a silicon CPU chip.
- Jed
