Thanks for this detail Jed, but no where do I see mentioned that this
material is a Pd-Ag alloy. The emphasis is on the production method, a
method that is normally applied to pure Pd. Consequently, the
confusion remains.
Ed
On Mar 13, 2009, at 3:27 PM, Jed Rothwell wrote:
Edmund Storms wrote:
A problem exists with respect to Type A Pd, which is claimed to be
used for gas purification. However, only the Pd075Ag25 alloy is
used for this purpose because this alloy, unlike pure Pd, does not
crack upon reacting with H2. Nevertheless, Fleischmann claimed the
Type A is pure Pd.
I do not recall him saying it was pure palladium. He mentioned pure
palladium in another context, quoted below. As far as I remember he
told me Type A is a palladium-silver alloy. Perhaps I am mistaken.
Anyway, here are some notes I made on this subject in 2000:
For many years Martin Fleischman has been recommending a particular
type of palladium made by Johnson Matthey for cold fusion
experiments. . . . He handed out several of these ideal cathodes to
experienced researchers, and as far as he knows in every case the
samples produced excess heat. The material was designated "Type A"
palladium by Fleischmann and Pons. It was developed decades ago for
use in hydrogen diffusion tubes: filters that allow hydrogen to pass
while holding back other gasses. This alloy was designed to have
great structural integrity under high loading. It lasts for years,
withstanding cracking and deformation that would quickly destroy
other alloys and allow other gasses to seep through the filters.
This robustness happens to be the quality we need for cold fusion.
The main reason cold fusion is difficult to reproduce is because
when bulk palladium loads with deuterium, it cracks, bends, distorts
and it will not load above a certain level . . .
Fleischmann wrote:
. . . We note that whereas "blank experiments" are always entirely
normal (e.g. See Figs 1-5) it is frequently impossible to find any
measurement cycle for the Pd-D2O system which shows such normal
behaviour. Of course, in the absence of adequate "blank experiments"
such abnormalities have been attributed to malfunctions of the
calorimetry, e.g. see (10). [Ikegami et al.] However, the correct
functioning of "blank experiments" shows that the abnormalities must
be due to fluctuating sources of excess enthalpy. The statements
made in this paragraph are naturally subject to the restriction that
a "satisfactory electrode material" be used i.e. a material
intrinsically capable of producing excess enthalpy generation and
which maintains its structural integrity throughout the experiment.
Most of our own investigations have been carried out with a material
which we have described as Johnson Matthey Material Type A. This
material is prepared by melting under a blanket gas of cracked
ammonia (or else its synthetic equivalent) the concentrations of
five key classes of impurities being controlled. Electrodes are then
produced by a succession of steps of square rolling, round rolling
and, finally, drawing with appropriate annealing steps in the
production cycle. [M. Fleischmann, Proc. ICCF-7, p. 121]
Fleischman recently gave me some additional information. The ammonia
atmosphere leaves hydrogen in the palladium which controls
recrystallization.
Unfortunately, this material is very difficult to acquire and there
is practically none left in the world, because Johnson Matthey
stopped making it several years ago. Palladium for diffusion tubes
is now made using a different process in which the palladium is
melted under argon. Material made with the newer technique might
also work satisfactorily in cold fusion experiments, but Fleischman
never had an opportunity to test it so he does not know. There
should be plenty of the new material available, so perhaps someone
should buy a sample and try it. Johnson Matthey has offered to make
more of the older style Type A for use in cold fusion experiments.
They will charge ~$20,000 per ingot, which is a reasonable price.
[As I noted here earlier, the price later went up because the price
of palladium rose. I think it was $50,000.]
Fortunately, the precise methodology for making the older material
is well-documented and an expert who helped fabricate previous
batches has offered to supervise production. So, if anyone out there
has deep pockets and once a batch of the ideal material to perform
bulk palladium cold fusion experiments, we can arrange it. I do not
know any cold fusion research scientists or institutions who can
afford $20,000 worth of material, but perhaps several people could
get together and pool their resources.
. . . When Ed Storms read this description, he immediately thought
of a number of important questions about fabrication techniques:
"What is the crucible made of in which it is melted? Pick-up of
crucible material can not be avoided. How is oxygen removed? Is
calcium boride used, which is the usual method? What is the boron
content?" Unfortunately, such details are trade secrets which
Johnson Matthey will not reveal. Fleischman does not know the
answers. Anyone who has a sample can quickly find out what elements
are present in the alloy, in what proportions. But questions such as
"How is the oxygen removed?" may not be as easy to ascertain. The
trade secrets are not what is in the metal, but how it got there and
why it stays.
I asked Fleischman how confident he is that this material is
effective, and how much batch-to-batch variability he observed. He
said that since 1980 he has used samples from eight or nine batches.
Only one batch failed to work, and was returned for credit.
In general, any material from Johnson Matthey works better than
palladium from other sources. The most dramatic proof of this can be
seen in M. Miles, "Anomalous Effects in Deuterated Systems." See
especially Table 10, p. 42, summarizing the effectiveness of
palladium from various different sources. The success ratio with
Johnson Matthey material was 17 out of 28 (17/28) compared to 2/5,
0/19, and 2/35 with other sources. Only the alloys fabricated in-
house by the NRL worked better, with a 7/8 success ratio. Miles
tested two samples of Type A palladium supplied to him by Fleischman
and Pons. Both produced excess heat at much higher power density
than samples from other suppliers (3 - 14 W/cm^3 compared to 0.3 -
2.1 W/cm3). Fleischman reported success with pure palladium, as well
as silver and cerium alloys. So did Miles, and he also had good
results with boron alloys. The NRL in Washington reported no heat
with samples from the same batches Miles tested, but their
calorimeter was an order of magnitude less sensitive than his (with
200 mW precision compared to 20 mW), so even if their samples had
produced the same level of heat Miles observed, they could not have
detected it.
In their Final Report, the NHE claimed that they used "the type of
palladium recommended by Fleischman and Pons" in a series of
experiments in the final stage of the project, after all else had
failed. This is incorrect, according to Fleischmann. They did not
have any of the Type A palladium. Perhaps they used some other
Johnson Matthey material instead. They have refused to reveal the
batch number or say when or where they acquired the material, but as
far as Fleischman knows, there was no Type A material available at
that time. When the NHE program began, Fleischman supplied them with
three Type A cathodes. Two of them produced excess heat, and one
failed because of a prosaic problem with the equipment. The NHE
disagrees with Fleischman's conclusion. Based on what Fleischmann
considers a nonstandard method of evaluating calorimetric data, they
say all three samples failed to produce heat. . . . Fleischman,
McKubre and Miles have criticized their methodology, in which a
single calibration pulse made a few days after the experiment
begins, when low-level excess heat is probably already present. (See
the Fleischmann quote above, and M. Miles, "Report on Calorimetric
Studies at the NHE Laboratory in Sapporo, Japan.")
. . .
I once asked Fleischmann how he learned about Type A palladium. He
said: "It is very simple. When we began this work I went to Johnson
Matthey, I told them what I needed, and they recommended this
material." . . . He often goes about doing things in indirect,
complex ways, but in this case he used the direct approach.
- Jed
