[NewCandle] New prospective matrix material for high temp LENR
Horace Heffner
hheffner at mtaonline.net
Sat Dec 27 20:14:32 EST 2008
Here is a whole new twist on dendrites (for me anyway) - dendrites
*in* glass.
http://www.sciencedaily.com/releases/2008/12/081219172129.htm
http://tinyurl.com/9a648r
Excess energy might be available from various hydrogen-to-lattice
reactions, including Ti + p and Ti+ D. Given Be can be a major
ingredient, this stuff is a prime candidate for LENR excess heat. It
would be interesting to test this material in powdered and thin film
form, though high tunneling rates probably have to be maintained via
thermal gradients and pressure gradients, which are easier to
maintain in bulk volumes.
Related PhD thesis:
"Designing Bulk Metallic Glass Matrix Composites with High Toughness
and Tensile Ductility"
by Douglas Clayton Hofmann
http://etd.caltech.edu/etd/available/etd-09102008-101837/unrestricted/
Hofmann_PhD.pdf
http://tinyurl.com/9m5nw5
From abstract at:
http://etd.caltech.edu/etd/available/etd-09102008-101837/
"Metallic glasses have been the subject of intense scientific study
since the 1960s, owing to their unique properties such as high
strength, large elastic limit, high hardness, and amorphous
microstructure. However, bulk metallic glasses have not been used in
the high strength structural applications for which they have so much
potential, owing to a highly localized failure mechanism that results
in catastrophic failure during unconfined loading. In this thesis,
bulk metallic glass matrix composites are designed with the combined
benefits of high yield strengths and tensile ductility. This
milestone is achieved by first investigating the length scale of the
highly localized deformation, known as shear bands, that governs
fracture in all metallic glasses. Under unconfined loading, a shear
band grows to a certain length that is dependent on the fracture
toughness of the glass before a crack nucleates and fracture occurs.
Increasing the fracture toughness and ductility involves adding
microstructural stabilization techniques that prevent shear bands
from lengthening and promotes formation of multiple shear bands. To
accomplish this, we develop in-situ formed bulk metallic glass matrix-
composites with soft crystalline dendrites whose size and
distribution are controlled through a novel semi-solid processing
technique. The new alloys have a dramatically increased room-
temperature ductility and a fracture toughness that appears to be
similar to the toughest steels. Owing to their low modulus, the
composites are therefore among the toughest known materials, a claim
that has recently been confirmed independently by a fracture
mechanics group. We extend our toughening strategy to a titanium-
vanadium-based glass-dendrite composite system with density as low as
4.97 g/cm[...]. The new low-density composites rival the mechanical
properties of the best structural crystalline Ti alloys. We
demonstrate new processing techniques available in the highly
toughened composites: room temperature cold rolling, work hardening,
and thermoplastic forming. This thesis is a proven road map for
developing metallic glass composites into real structural engineering
materials."
Best regards,
Horace Heffner
http://www.mtaonline.net/~hheffner/
More information about the NewCandle
mailing list