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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Carrier Recombination Lifetime in Thermal Equilibrium
All the books I read talk about carrier recombination lifetime when the semiconductor material is pushed out of equilibrium. But let's say the material is in equilibrium ( where generation and ...
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What happens when slip direction is the same as applied force?
Using the equation
$$ \tau R = \sigma y \cos \left( \phi \right) \cos \left( λ \right) \tag{1} $$
means that when the angle $\phi$ between the tensile axis and slip plane normal is $90$, $\cos \left( ...
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Why don't all metals have closed pack structures?
A lot of times, in my materials classes, metal atoms' behavior during deformation is described like a bunch of stacked balls. In my introduction to material class, our professors explained that metals ...
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Cross Section Area
When bending sheet metal in a press brake, it stretches slightly. For example, if I had a piece of steel 200 mm long by 1 mm thick and bent it in half, the two legs will each be longer than 100 mm so ...
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Is there a way to theoretically estimate the restitution coefficient of a rubber ball?
Let's consider a rubber ball like the ones shown in the picture:
When dropped onto the floor, the ball will rebound, but it won't regain its initial height.
The restitution coefficient is defined as ...
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Changing element and isotope ratio ratio in material in space
Suppose we have a satellite orbiting Earth with a component made of 6061 aluminium alloy.
Would cosmic radiation cause the element and isotope ratio of the component to change in a clearly measurable ...
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What is a general definition of bulk modulus?
For a perfectly elastic body, Bulk modulus always remains constant and is defined as,
$$B=-V_i \frac{\Delta P}{\Delta V} \tag{1}$$
Which means,
$$B \left(\frac{V_f -V_i}{V_i}\right)= -(P_f-P_i)$$
But, ...
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Does glass slowly (invisibly) degrade until it breaks?
(This question is about non-tempered glass.)
I broke my favorite glass (tumbler) today, dropping it in my (ceramic) sink while trying to refill it. :(
I'm kind of a klutz - that's far from the first ...
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Does a noise protection wall cancel out sound on the opposite side of the acoustic source?
My town wants to build a noise protection wall on one side along railway tracks. Houses are on both sides of the railway tracks. Obviously the noise protection wall will cancel out sound on the ...
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Why is red the brightest in the emission spectra of Hydrogen Gas?
I was studying a very simplified intro to Spectroscopy.
The following diagram shows the emission spectra of Hydrogen Gas:
Credit: NASA, ESA, and L. Hustak (STScI)
My Question: In the spectra, the ...
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Do contact forces form a field/wave?
Non-contact forces like gravitational forces exist between two objects in any medium because of the establishment of a field/wave.
Since at an atomic level, 'physical' contact won't really be possible ...
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What is the meaning of screened potential? [closed]
I keep reading that it is supposed to account for the particle-medium interactions, but why do we need another potential besides the Coulomb one that includes the interaction between every particle in ...
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Can the polar crystalline polymorphs of PVDF (beta, gamma or delta) be tuned to respond to ultra-high frequency sources?
I am interested in determining whether or not it is possible to tune, by polling and/or nanomaterial loading, PVDF such that it would respond to stimulus from ionizing radiation such as Gamma rays.
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Determining the condcutivity of a material by method of contactless resistance caused by putting a sample rod in the inductor of an RLC circuit
I'm doing an experiment where I'm trying to determine the conductivity of a material by putting a sample rod in the center of a coil which is a part of an RLC circuit with an AC generator.
I was told ...
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How can I assess the validity of a time-temperature superposition (TTS) master curve obtained from stress relaxation experiments?
I'm working on analyzing the viscoelastic behavior of a elastomer using time-temperature superposition (TTS) techniques based on stress relaxation experiments. I've come across various conditions for ...
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