Soft condensed matter physics

[Astronuc]

Soft matter or soft condensed matter is a type of matter that can be deformed or structurally altered by thermal or mechanical stress which is of similar magnitude to thermal fluctuations.

The science of soft matter is a subfield of condensed matter physics. Soft materials include liquids, colloids, polymers, foams, gels, granular materials, liquid crystals, flesh, and a number of biomaterials. These materials share an important common feature in that predominant physical behaviors occur at an energy scale comparable with room temperature thermal energy (of order of kT), and that entropy is considered the dominant factor. At these temperatures, quantum aspects are generally unimportant. When soft materials interact favorably with surfaces, they become squashed without an external compressive force.

https://en.wikipedia.org/wiki/Soft_matter

Pierre-Gilles de Gennes, who has been called the "founding father of soft matter," received the Nobel Prize in Physics in 1991 for discovering that methods developed for studying order phenomena in simple systems can be generalized to the more complex cases found in soft matter, in particular, to the behaviors of liquid crystals and polymers.

I'm wondering how this applies to metal, or more particularly, to alloys with a homologous temperature of 0.8 or greater.

I discovered the subject matter when it was called to my attention.

ESPResSo++: A modern multiscale simulation package for soft matter systems​

https://www.sciencedirect.com/science/article/abs/pii/S0010465512004006. (subscription/purchase required, or access through one's institution)

Code modernization strategies for short-range non-bonded molecular dynamics simulations
https://arxiv.org/abs/2109.10876

 

[pines-demon]

I'm wondering how this applies to metal, or more particularly, to alloys with a homologous temperature of 0.8 or greater.

How "what" applies to a metal? Soft matter physics? It does not.

Soft materials include liquids, colloids, polymers, foams, gels, granular materials, liquid crystals, flesh, and a number of biomaterials.

 

[renormalize]

How "what" applies to a metal? Soft matter physics? It does not.

So you assert that the metals mercury at room temperature and aluminum at 660°C are not soft materials?

 

[Astronuc]

How "what" applies to a metal? Soft matter physics? It does not.

I was thinking of the point at which soft matter physics principles would apply to metals, or more particularly alloys, as they approach their respective melting points. Before they achieve melting, they more or less flow, or are easily deformed, like a viscous fluid, as opposed to alloys at or above melting, which obviously flow and can be poured.

 

[pines-demon]

So you assert that the metals mercury at room temperature and aluminum at 660°C are not soft materials?

I was thinking of the point at which soft matter physics principles would apply to metals, or more particularly alloys, as they approach their respective melting points. Before they achieve melting, they more or less flow, or are easily deformed, like a viscous fluid, as opposed to alloys at or above melting, which obviously flow and can be poured.

I mean sure for liquid metals there is a whole field of research, if that is soft matter or not it is the same as asking if fluid mechanics is in or not. That said, phase transitions in simple metals are relatively straightforward to describe, it is not the kind of systems that people study in soft matter.
For metals near the melting point, there is probably a rigorous entropy argument to be made here to distinguish them from the rest of soft matter. Normal elasticity theory may do the work for metals in this case.

Now if you have a more complicated solid or a high-entropy alloy, you have all kind of glassy phases that are described by the same techniques developed in soft matter physics.