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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Does glass undergo internal damage in a similar way to wood?
Does glass undergo internal damage in a similar way to wood when struck hard, even if it doesn't visibly break, and is this damage accumulated gradually over time, or does it occur as a binary ...
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In solid state physics and Density Functional Theory, how are Van Der Waals forces modelled?
Given a material, I'd like to know how to treat VdW interactions among layers. Specifically I'm using Quantum Espresso, an open-source suite based on Density Functional Theory, and I'd like to know ...
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How strength of RF coupling depend on the antenna material?
If we place different materials in the microwave owen, they will get hot at different speeds. For instance meals get hot really fast. What material property decides on the strength of the coupling? ...
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Are there any material coatings that would currently be effective to counter the rise of directed energy weapons?
I've been reading into directed energy weapons recently, and they seem like they're going to be a gamechanger. I'm just curious as to material countermeasures. I've learnt that some dielectric mirrors ...
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Mechanical wave traveling time in a medium
This stems out of my personal curiosity and it's not related to any homework of sort.
Suppose I have a table made of some uniform substance (like plastic), and then I strike some point of the table ...
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Structural notation for multi-element FCC crystal structures
I was wondering if different compound FCC structures share any kind of indicator or structural notation which I could use to find and categorise them.
To clarify my problem: the FCC L12 structure, ...
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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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Materials known to have higher density than Osmium at at high pressure and/or low temperature
This question is basically a modification of this.
It's well known that Osmium is the densest material you can find at room temperature and pressure. I am curious at higher pressures (and lower ...
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Does the compressive strength of materials increase if they are placed under hydrostatic pressure?
Normal measurements of compressive strength work by compressing a sample with an hydraulic press and see when the sample deforms plastically or cracks.
Now if pressure is applied on the surfaces of ...
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Why are new compounds in materials science investigated and categorized under low-temperature thermodynamic properties? [closed]
Is it solely because these materials are usually not as interesting in ambient temperatures?
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Question about the elasticity matrix in metals
The most general anisotropic linear elastic material has 21 elastic constants. I am working with an HCP material and I found that it has 5 independent elastic constants. I am programming a subroutine ...
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LK-99 a total waste? [closed]
It looks like LK-99 is not what it was purported to be. Disappointing but not surprising.
However did anything of substance or new ways or approaching the problem brought to light in the way it was ...
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Question about k.p Method
I am reading David Miller's quantum mechanics, and I do not understand the derivation for k.p method:
We are particularly interested in the behavior of semiconductors near to maxima and minima.
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Difference in magnetic permeability of High tensile strength steel and Mild steel
Mild steel has a relative magnetic permeability of 2000. High tensile steel is a type of mild steel with elements other than carbon. I need to know whether this would impact the relative permeability ...
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Why isn't the tensile/compressive strength of a material dependent on its atomic bond strength? [closed]
The melting or sublimation point of a material indicates the strength of the bonds between its molecules being high, as the material remains solid despite the amount of heat energy present. Carbon, at ...
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Why do physicists primarily study TMDCs when researching 2D materials, and not focus as much on many other 2D materials? [closed]
Why do physicists primarily study transition metal dichalcogenide (TMDC) monolayers when researching 2D materials, and not focus as much on many other 2D materials?
Other 2D materials also have ...
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Ductility of LK-99
I’ve heard about the new proposed superconductor known as LK-99, one thing I’m wondering that I haven’t yet gotten an answer to is how ductile is it? I.E. how easy would it be to make wires out of it?
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Question about the general Schmid’s law expression to calculate the critically resolved shear stress
I have a question about Schmid’s law for an arbitrary stress state. I found conflicting expressions and I would like to know which one is correct.
$\boldsymbol{s}$: slip direction
$\boldsymbol{n}$: ...
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How to calculate the expansion of metal on heating? [closed]
Is there any possible way to calculate the temperature required for a metal to expand or bend, with provided dimensions?
For example, take Mild steel with a length of 100mm, width of 150mm, and ...
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Material strength against kinetic energy instead of force [closed]
Knowing the strength of concrete you can get the mass of an object put on a concrete block is able to withstand on given area. As for a falling object, kinetic energy itself doesn't translate to force,...
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Fourier Transform of Dielectric Function in 2D
According to "Dielectric screening in two-dimensional insulators: Implications for excitonic and impurity states in graphane", https://doi.org/10.1103/PhysRevB.84.085406, the Fourier ...
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How would I understand Hysteresis from scratch? [closed]
I wanted to learn about Hysteresis and I know the basic undergraduate level of 'Mechanical properties of matter".
Can anyone please help?
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Drift current and diffusion current in depletion region of diode at equilibrium
The diffusion current for a diode at the edge of the depletion region is $I_D=I_S(e^{qV_A/VT}-1)$. Under an unbiased condition$(V_A=0)$ at equilibrium, $I_D$ will be $0$. The drift current should be ...
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Equations of motion for two masses connected by the Kelvin-Voigt Model
I have a system where two particles $x_1$ and $x_2$ in one dimension are connected by a spring and a dash in parallel. This is analogous to the Kelvin-Voigt model for viscoelastic materials. The two ...
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Why do good materials operate in non-equilibirium conditions?
If we look at the majority of useful or industrial materials surrounding us, like metallic alloys, glasses, ceramics, or plastics, it is often the case that these materials went through really hard ...
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How does restoring shear forces arise (in elastic conditions)? Do they arise from central forces or not?
When you apply a shear force onto a solid piece of material (say a block on a surface or a cantilever
beam with a load) that creates shear stress in the elastic regime, there is a restoring force that ...
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Effective ionic conductivity of composite
Suppose I have two ionic conductors, such as two ionic solids, each with a well defined specific conductivity.
If I take a piece of length $L$ from each conductor and put the two pieces in contact, ...
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Why are systems operating far from equilibrium more efficient?
In many (biological and living systems) physics courses I encountered the notion that systems operating far from equilibrium are related with more efficiency with regard to their specific tasks.
One ...
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Is compressive strength closely related to Mohs hardness?
Compressive strength is how much inward force a given area of material can withstand before failure. The force tries to compress the atoms closer together.
Mohs hardness is the difficulty of a ...
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Modes of vibration
I've been thinking that 'modes of vibration' refers to the frequencies which produce standing waves in a system. But now I'm confused, because ChatGPT gave me the below response for my question.
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How to derive properly the stress-strain relation of an hyperelastic material?
I'm trying to implement a Yeoh hyperelastic model for a FEM simulation. The program requires a function that returns the second Piola-Kirchhoff stress tensor $\mathbf{S}$, with the Green-Lagrange ...
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Material which changes color with charge
Is there a material which changes color when electrically charged (positively or negatively, doesn't matter)? If so, how does it work? If not, is it theoretically possible, and if it's not possible, ...
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Why Energy varies linearly in case of graphene and other Weyl semi-metals and not in conventional semi-metals?
The Energy-Momentum diagram in case of graphene is very unusual as it is conical in shape instead of paraboloid. This means that $E=\mathrm{E}_{0}^{}+ (\hbar^{2} k^{2}/2m)$ is not followed by Weyl ...
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Rope strength necessary to stop a fall
Just a random thought experiment, that got me confused.
So when you buy a rope you get info about Tensile Strength(lbs) or kg let's say 1000kg.
That means it can hold an object of that mass.
But the ...
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Since when has the formula $I = \frac{b h^3}{12}$ (second moment of area) has been discovered and applied in building construction?
A question about history of physics: since when and by who has the formula for the second moment of area
$$I = \frac{b h^3}{12}$$
been discovered? When has it started being applied in building ...
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Confusion about how to read the energy band diagram
I am not sure if I understand the energy band diagram correctly. In a pn junction situation below, before the p type material come into contact with the n type material as in figure a), an electron at ...
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volume fraction of Ice Ih
we know that the volume fraction of a lattice like HCP is 74%. how can I calculate the volume fraction of a lattice of Ice Ih?
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Materials and sound
I’m working on a novel musical instrument that will be made with metal (brass, aluminum,…) round bars. I’m looking for a formula that will give the note (frequency) for a given metal, length and ...
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Can the scratch susceptibility of a given material be determined, given the breaking strength of another?
There was a post in Seasoned Advice which piqued my personal interest (seeing as how I'm ABC myself). Rice cooker pots are by no means "cheap", so I thought I'd look into it myself in order ...
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Definition of carrier concentration $p = 0.1$?
When reading some literature in physics I came across expressions like:
"Our super-high-resolution ARPES experiments reveal an insulator–superconductor transition at a critical doping level of P ...
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Large table of pairwise friction values?
Small table of pairwise friction coefficients (i.e., "rubber vs concrete", "leather vs oak") exist online:
https://www.engineeringtoolbox.com/friction-coefficients-d_778.html
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Material or rather a layer to increase dielectric strength
Is it possible to increase the dielectric strength of any or some materials by adding a certain layer on its surface?
And do you know any? The purpose is lastly to improve the electrical breakdown.
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Would sound get weaker in metal faster than in air over the same distance?
I'm finally closing some gaps in sound waves, so forgive me for lots of questions.
In metal, it's said sound travels fastest. The reason is molecules are tightly packed(more dense) in metals than in ...
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How to find a proper basis defined on (111) plane such that only one component of piezoelectric field is nonzero?
I am considering a material which has cubic crystal structure (in particular, zincblende). The space group is $T_d^2 F \bar{4}3m$. In particular, I am concerned with finding the piezoelectric field in ...
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Vinyl Records and timbre
I've read other answers about how vinyl records reproduce sound, but they don't quite address a main thing I'm curious about.
Play Middle C on a piano or a Clarinet, its the same note that can be ...
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Why does bunched up aluminum foil become so extremely hard to compress?
I noticed that whenever I bunch up aluminum foil (into a ball), it becomes extremely hard to compress.
If I use another piece of the same amount of aluminum foil, and keep folding it in, I arrive at ...
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Relation between Youngs Modulus and Co-efficient Of resistitution [duplicate]
I was thinking that $Y$ (youngs modulus) should be dependent on $e$ (Co-efficient of Restitution) as COR explains the separation/approaching ratios of velocities of 2 objects colliding, The velocity ...
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Prove that an isotropic substance has only two elastic constants
I've been following the derivation from Ch. II-31 of Feynman's Lectures, and there is a bit that I don't understand. We start from the relation between the strain $T_{ij}$ and the stress $S_{ij}$, $$...
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Raman Spectroscopy of Graphene
Why do graphite and graphene have different peaks in Raman Spectroscopy? Does a double layered graphite give us a graphite peak or a graphite peak?
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How can things around us have different colours if they have specific emission spectra?
Objects appear in different colours because they absorb some colours (wavelengths) and reflect or transmit other colours. The colours we see are the wavelengths that are reflected or transmitted.
As ...
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