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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Why defects don't have an effective charge in metals?
In semiconductors and insulators, crystal defects, e.g., vacancies and interstitials, are treated as having an effective charge. In metals, however, defects are treated as neutral. I can expect that ...
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Can you perfectly control electric currents' behavior in anisotropic media?
I'm an undergrad who is learning recently about anisotropy w.r.t. E&M. I understand that in anisotropic media the behavior of electric currents and other E&M aspects can be very unpredictable ...
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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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Is Young's modulus of elasticity a measure of ductility?
I've learnt that the Young's modulus of elasticity is defined as the ratio of stress and strain when the material obeys Hooke's law. So it has no significance beyond the proportional limit in the ...
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How to estimate the impact force of a martial artist breaking bricks?
I was watching a martial artist breaking a stack of 9 out of 10 concrete bricks. I noticed that the last didn't break. It made me wonder if this would allow calculating the force dealt to be ...
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Calculating tension in a pressurized container [closed]
Suppose I have a pressurized spherical container made of 1 mm thick aluminum. The container has pressure P and internal volume V. How would I calculate the tension in the aluminum?
The aim of this is ...
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Is X-Ray-Emission-Containing Phosphorescence possible or is it limited to Immediate-Emission XRF?
This was a random thought that I wanted to follow up on. I know some materials can take in and kick out X-Rays in XRF (Though most x-ray scintillators tend to emit mostly visible light, not x-rays). ...
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Potential of Monolayer Graphene as a High-Precision Cutting Material
"I am exploring the use of monolayer graphene as a cutting material for high-precision applications. We know that graphene has exceptional mechanical properties, such as high strength and ...
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Friction and electromagnetic force
What is the relationship between friction and electromagnetic force? At microscopic level, how does electromagnetic force cause friction?
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Why do some metal oxides behave as n-type or p-type extrinsic semiconductors without adding a dopant?
There are some metal oxides that are said to be extrinsic n-type and p-type semiconductors without having been doped. For example, $\mathrm{In_2O_3}$, $\mathrm{SnO_2}$ and $\mathrm{ZnO}$ are said to ...
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What is the thermal expansion equation for a cylinder (plane strain)?
I know under plane stress assumption it would be $$dR=\alpha R_0 dT$$.
What about plane strain?
I tested it in Abacus and plane strain had a higher radial displacement than plane stress assumption.
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Metal vs Cardboard: which liner for a solar oven would allow it to reach a higher temperature, and why?
Lets's say I make two solar ovens. They each have a set of reflectors angled to direct sunlight into a box topped with glass, and all other sides of the box are covered with insulation that can stand ...
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What is the material with the highest mass enhancement factor?
The electron phonon coupling mass enhancement factor $\lambda$ is a measure of the strength of this coupling. This quantity can be measured experimentally. For instance, Pb has a factor of 1.55 ...
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How can we calculate entropy produced by plastic deformation in this example?
Suppose we have a massless spring of spring constant $k$ attached to a mass $m$ at equilibrium position $x_{0}$ at temperature $T$. The mass may oscillate in one dimension only for simplicity. We ...
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Why do different materials reflect different light?
So, as far as I understand, white light contains photons of all energy levels. These hit a material, say iron. The photons that are below the energy level to move electrons just pass through. The ...
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