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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How can one reasonably theoretically model polycrystalline materials?
Many techniques are taught in advanced solid state courses but they are almost all derived for perfectly crystalline materials. For example, band structure really only appears theoretically when you ...
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Non-glassy amorphous solids
According to Wikipedia:
A glass is any "solid that possesses a non-crystalline (that is, amorphous) structure at the atomic scale and that exhibits a glass transition when heated towards the liquid ...
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What causes these 2nd order knot shapes and why?
I twisted a (broken) rubber band around multiple revolutions. Initially it created what I call first order twists, where the "wave-length" of the twist got shorter and shorter across the ...
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Are solid materials ergodic systems?
It is stated that a system is considered ergodic if it can access all available states with the same energy in the phase space over long periods of time and that time average and ensemble average of ...
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How can you separate the band structure of two materials in a heterostructure?
I have a heterostructure with two layers A and B. I have calculated the wave-function, and properties (bands and dos) of the AB heterostructure as well as the A and B materials separately by removing ...
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Magnetic susceptibility
Currently I'm doing the simulation of Ising Model with Monte Carlo method. I got a curve which the magnetic susceptibility diverge (precisely due to finite size effect, it is not diverge but show the ...
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Effects of annealing on defects in solid
What is the effect of annealing on the defects present in the sample? Does it remove defects in the sample? Is there any chance that due to annealing the point defects present in the sample combine to ...
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What is a ferroelectric metal?
I was reading online about ferroelectricity, and came upon the topic of ferroelectricity in metals. The main cited paper is the one below by Anderson and Blount in the 1960's
Symmetry Considerations ...
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Stress-Strain behavior of ceramics at high temperatures
Can someone explain to me why do we observe the peak in the stress strain behavior at 1400 C and then a sudden decline followed by gradual increase? What does it signify? Does it have anything to do ...
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Physics simulator to test the properties of metal alloys
In my free time I enjoy designing and invent random devices that do a variety of things and as part of this I design the materials that would be used to make the object, taking into account the needs ...
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Material that changes solubility when electric potential is applied
I am looking for a material witch is easy to deposit in thin films and which changes its solubility if a electric potential is applied.
Do you know of any such materials ?
EDIT: This is for what I ...
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What's the difference between critical load and yield stress?
So far, I have learned of three quantities that are related to the failure of a beam (axial and longitudinal loads). The first illustrates the stress under which balsa wood will undergo plastic ...
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Why do elastic bands stretch?
From what I know already rubber bands are made up of long straight molecules (alkanes I assume?) and when unstretched these are a mess of coiled and cross linked. And by stretching them you untangle ...
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What is so special about octahedral stresses?
Octahedral stresses are described here. Octahedral shear stress failure criterion is also called as distortion energy failure criterion. Moreover, famous von Mises yield criterion is related with ...
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can freezing water burst a short pipe if the pipe is open at both ends?
My question:
If a thin-walled copper or brass pipe is open on both ends (let's dimension it at 60 cm long by 8mm inner diameter, as an example) and is filled with slightly salty water (estuarine ...
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How do spongy substances crack or tear?
I read that there is a length (the Griffith critical crack length) beyond which cracks start to become self-propagating. If a crack in a sponge very quickly reaches a hole and stops propagating how do ...
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nano materials and material science
As a part of my major project I have taken plates of Al6061 samples and butt welded them with friction stir welding machine. During welding I have incorporated metal oxide Nano particles into weld ...
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How does flow rate affect plume dynamics and film properties in PLD?
So I use a home-built Pulsed Laser Deposition(PLD) system to deposit metal oxide thin films. I use a $ 248\ \mathrm{nm KrF}$ laser. I recently deposited two films under slightly different conditions. ...
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How "steady" are screw threads?
I have a setup whereby two stainless steel end caps screw into a similar tube about 100mm in length and 25mm internal diameter. Thread is fairly standard, and is finger tight.
The question is: ...
user56903
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If we put diamagnetic material under strong electromagnet, would the opposing magnetic fields be strong enough to attract ferromagnetic materials?
Suppose we put a diamagnetic material (such as Bismuth or Pyrolytic Carbon) under a strong magnet (see image below). It would create opposing magnetic fields. Would the opposing magnetic field be ...
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What material could be used to study magnetic phase transitions in a college laboratory exercise?
I am working to develop a simple laboratory exercise in solid state physics to be conducted by fourth year students of physics. The idea of the exercise is for the student to get some experience in ...
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Why can thermal shocks damage/break materials?
When an object is heated a lot and then brutally cooled down or vice-versa, it can crack or even break spectacularly. What happens inside that makes it do that?
Is it only because the hot core swells ...
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Where does one find pair-correlation functions for various materials?
What is the canonical source for finding pair-correlation functions for atoms in various materials? I am interested in both numeric computations and experimental measurements (like might be obtained ...
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Does graphene actually remain strong for macroworld engineering?
I heard that people envision strong structural materials made out of graphene, but I heard it may weaken when being stack in layers. Is graphene viable for macroworld structural engineering or is it ...
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Why is BaTiO3 piezoelectric, but CaTiO3 not?
When BaTiO3 is cooled below the Curie point (120°C), the cubic structure changes slightly, so that $Ti^{4+}$ shifts by 0.006nm away from its position at the center of the cube. I don't know why this ...
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What ring weave disposition should be the most resistant against stabbing and/or how to determine it
In a website that I am studying so I can build a Chain Mail, I have found a page featuring a lot of different Ring Weaves to build them.
I want to determine which one is the best to provide ...
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What would be the best material to reflect radio waves?
From what I could gather after a quick search on the internet, it would seem that any material can reflect or absorb RF waves but thickness matters. It's obvious that most parabolic dishes are made ...
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How does one use empirical pseudopotentials to model disordered random alloys?
How does one use empirical pseudopotentials to model disordered random alloys?
I am working on modeling random alloys and came across the following paper: https://link.aps.org/pdf/10.1103/PhysRevB.85....
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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 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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Are YBCO or BSCCO rods able to superconduct at full $J_{c}$?
My understanding of the state of the art for superconducting cables is that ceramic powder is manufactured, then it's packed very tightly into a silver tube. I'm not sure how this is supposed to solve ...
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How can I remove a layer of Silica from a rough IN718 surface?
Our rocketry group is designing a biliquid ethaLox Inconel 718 additively manufactured chamber.
We are looking into using Tetraethyl orthosilicate as a fuel additive to reduce the heat flux in our ...
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Phase transition detected using Raman spectra is not visible with XRD analysis
I am currently trying to analyse a paper in which perovskite material is pressurized and they observe the variation in structural properties using Synchrotron XRD and Raman Spectroscopy. Now the ...
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Why does a spring work the way it does?
I am wondering if anyone can explain what exactly makes the shape of a spring so good at creating something so elastic and good at converting between kinetic and potential energy.
The metal itself isn'...
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How porous can a ferromagnet before turning paramagnetic?
As there is an inherent size limit to magnetic domains, as the porosity of a ferromagnetic material increase, there will be a point in which a static magnetic field will not be possible.
There are a ...
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