An important discovery and it must apply to other elements as well. On a practical level it may be possible to melt metal and also remove it without actually heating the metal thus preserving structural crystallization itself.
Metal may then be properly annealed but then shaped with room temperature surface melting. Rather an important tool.
And who imagined this at all as potentially this (easy)?
.
Scientists find way to melt gold at room temperature
Melting
gold normally requires temperatures upwards of 1,064° C (1,947° F), but
physics is never quite that simple. A team of researchers has now found
a way to melt gold at room temperature using an electric field and an
electron microscope.
Although
we're all familiar with the phenomenon of melting, most of us don't
really think about the physics behind the process. Essentially, when
something melts all that's happening is that the bonds between its
molecules break down and they begin to move more freely. For instance,
they might transition from the well-ordered structure of an ice cube to
the less ordered state of a shapeless puddle of water.
Heat
is the usual trigger for the change, but it's not the only one –
pressure plays a part too. Experimenting with those conditions has let
scientists do all sorts of unexpected things recently, like making water freeze at temperatures well above its usual boiling point.
In
the new study, the researchers tested another trigger: an electric
field. The team placed a small piece of gold in an electron microscope,
and observed it at the highest level of magnification. Then, they slowly
ramped up the strength of an electric field to see how the gold atoms
reacted.
When
they looked back at the data afterwards, the researchers realized that
the electric field had excited the atoms in the top layers of the gold.
That made them break free of the bulk of the object, effectively melting
the material at room temperature. The change was also reversible, as
switching off the electric field can solidify the gold again.
"I
was really stunned by the discovery," says Ludvig de Knoop, first
author of the study. "This is an extraordinary phenomenon, and it gives
us new, foundational knowledge of gold."
The
team isn't entirely sure how the technique works to melt gold at
ambient temperatures, but it may be due to a phenomenon known as
low-dimensional phase transition. The researchers plan to investigate
that in the future, which may help unlock some applications for the
discovery.
"Because
we can control and change the properties of the surface atom layers, it
opens doors for different kinds of applications," says Eva Olsson, an
author of the study. "For example, the technology could be used in
different types of sensors, catalysts and transistors. There could also
be opportunities for new concepts for contactless components."
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