Questions tagged [material-science]
The study of how the properties of matter arise from its structure at all scales and of how processing can be used to modify those properties (often in pursuit of a specific application).
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Force problem related to adhesive and bonding
I have two PCBs (printed circuit board), and they are glued by adhesives, as show in the pictures. And the location of the adhesives are indicated on the picture (please notice that NO adhesive is ...
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Why does the overhand knot jam but the figure-8 knot doesn't?
After tensioning a rope with an overhand knot in it, it is often very hard if not impossible to untie it; a figure-8 knot, on the other hand, still releases easily.
Why is that so? Most "knot and ...
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Why don t tiny cracks heal in metal via cold welding?
Or in other words: how do cracks inside metal survive given the phenomenon of cold welding?
If metal is overstretched, one or more fine cracks result along imperfections in the metal lattice. Why don'...
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Reference guide for standard descriptions of materials
Is there any reference that has a coherent list of materials and what type of approximate Hamiltonian to best describe them with (where it is known). Particularily I am looking for the following bits ...
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Can a bulk crystal have a spontaneous quadrupole moment?
Crystals of polar space groups e.g. ferroelectrics can have a spontaneous electric dipole moment. Is it possible for a crystal to have a spontaneous electric quadrupole moment (and higher order terms ...
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Is there a material with non-monotone density dependence on pressure?
Is there a material with such non-linear effects (including chemical reactions, phase transitions etc ...) so that there would be range where pressure increase would yield density decrease?
What ...
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How small can velcro be?
Note: "fiber" refers to individual hooks and/or loops.
Imagine two flawless graphene sheets, one with atomic diameter hydrocarbon loops attached to one face, one with atomic diameter ...
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Sound conduction in a stethoscope
i am trying to build a stethoscope and since i have no idea about physics and acoustics i wanted to ask some questions, hoping Somebody can help me.
I mainly have some questions regarding the tubing ...
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Is there a material that allows light to pass perpendicular to the surface, but reflects at an angle?
This is inspired by Michael Steven's new video about optics.
He shows off Selenite, which has the property that light entering on one side travels perpendicularly down the crystal until it exits the ...
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Why aren't all insulators transparent, since they have a large band gap?
According to Floris' answer in this link, diamonds are transparent as they have large band gaps while graphite is black as it is a conductor.
As electrical insulators generally have a large band gap, ...
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What is the physical reason behind the negative differential resistance (NDR)?
As you know, there is an effect called negative differential resistance in some electric devices and materials, but I could not find any article or book or any other reference to talk about the ...
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How to know chern number of Massive Dirac Hamiltonian
I need your help.
I consider this Hamiltonian
$H=v(\xi k_y \sigma_x+k_x\sigma_y)+m\sigma_z $
$\xi$ is valley index. It is +1 (at K' valley) or -1 (at K valley ).
I want to know Chern number of ...
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What does a sheet of graphene look like?
What does a sheet of graphene look like?
At one atom thick, is it visible to the naked eye?
Can it be handled (by hand) with being torn?
Can it be felt at all?
[Assuming a large enough sheet ...
user56903
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What makes Obsidian edges sharper than other glass?
Obsidian is a volcanic glass with a reputation for being extremely sharp. Some surgeons use obsidian scalpels rather than high-quality steel surgical scalpels.
At the same time, glass blades are used ...
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A physicists perspective on a material science/engineering problem
I am looking into some research that involves engineering and material science. As a physicists I wondered what other physicists would think of this problem and how they would approach it. Much of the ...
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