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).

learn more… | top users | synonyms

0
votes
1answer
75 views

Applications of partial differential equations in material science [closed]

I've been asked to find a partial differential equation that has applications in material science. However we are not allowed to use the heat equation. I have found Fick's laws (basically the heat ...
0
votes
0answers
52 views

Steel and aluminum fatigue limit

Is it true that steel has a fatigue limit? Is it true that past a certain number of stress strain cycles, steel will last indefinitely if its ultimate strength after the specified number of stress ...
0
votes
1answer
92 views

Plasma frequency

I have a neutral plasma and I need to solve Maxwell equations given the charge and current densities on the plasma. In order to do it I need to know the electrical permittivity $\varepsilon$, I've ...
2
votes
3answers
195 views

Materials with directional friction property?

At the macroscopic level a simple metal file or rasp creates a large amount of friction in one direction and a much smaller amount in the opposit direction. Shark skin displays the same properties due ...
1
vote
0answers
65 views

Finding the strains from a 0, 90 rosette - Mohr's circle

I have used a strain rosette with two gauges at 0 and 90 degrees to find strain on a beam under force and an trying to plot Mohr's circle for the problem. As the gauges are at right angles finding the ...
1
vote
3answers
480 views

Melting and Boiling Points of Odd Materials

In Chemistry, I was taught that there are three main states of matter: solid, liquid, and gas, and that heat and pressure determine that state. For some substances, the line is blurry between them. ...
-1
votes
1answer
27 views

will my duraflex seams melt over a fire

Good day ladies and gentlemen, i do realize it may seem like a welding question but i assure you it is physics related. i have built a non pressurized boiler that contains water to be used over an ...
1
vote
4answers
2k views

when we rub objects together, what determines which material will pick up electrons?

For example We know glass when rubbed by silk will become positively charged while the silk will be charged negative. What exactly makes glass appropriate for losing electrons in that experiment? (
0
votes
4answers
298 views

What is Conductance?

What is conductance? I am being said that conductance is inverse of resistance?I do know that resistance is the opposition to the flow of current but do not get conductance? I do know that:it is ...
0
votes
0answers
181 views

Find the maximum allowable bending moment

A rolled steel universal I-section beam with a serial size of $406\times178$ has a mass of $60$kg/m. What is the maximum safe allowable bending moment this beam can sustain,given that the maximum ...
2
votes
1answer
31 views

Would it actually be possible to preserve a snow flake?

In episode one of season 3 of The Big Bang Theory Leonard offers Penny as a gift a snow flake he says he preserved in some kind of resin, having it brought from the North Pole. Is this purely ...
0
votes
0answers
11 views

Equivalence of Bulk Modulus Definitions [duplicate]

Per http://en.wikipedia.org/wiki/Bulk_modulus, $K=-V\frac{\mathrm d P}{\mathrm d V}$ and $K=\rho \frac{\mathrm d P}{\mathrm d \rho}$ are two equivalent definitions for $K$, the bulk modulus. How do ...
1
vote
2answers
61 views

Piezoelectric polarity

After a few days, I cannot find an answer to this question: Besides mechanical stress, is there another way to induce a negative charged surface on quartz? Note: several scholarly articles kept ...
-1
votes
2answers
66 views

What temperature will create amorphous TiSi?

At what temperature will create amorphous TiSi? I think it's around 500 Celsius but I'm not sure.
0
votes
1answer
34 views

magnetostrictive effect due to earth's magnetic field

is there any magnetic field sensor,which produces stress or strain as output,when that sensor is sensing earth's magnetic field on the surface of earth(0.25 gauss to 0.65 gauss)?or any ...
0
votes
0answers
42 views

Martensitic transformation in ceramics

What is the specification of Martensite (displacive) transformation in ceramics comparing to yhe one in metals? I just know about Martensite transformation in metals. For example, these ...
0
votes
0answers
36 views

coherent grain growth

What is the driving force for growth of coherent precipitates in the matrix? The driving force for growth of incoherent precipitates in the matrix is concentration slope between tiny and large ...
2
votes
0answers
26 views

Does the surface of austenitic steels have an especially “dynamic” phase somewhere between 100 and 200 Celsius?

There is lots of kitchen lore about pans. One popular concept are the "pores" of a steel pan surface, which are the reason why food sticks to the pan when it's not heated properly. I don't know much ...
1
vote
0answers
59 views

How much will a round tube deflect under load? [closed]

I'm trying to determine the materials I need to complete a hobby project, and I'm having trouble estimating how much flex a given steel tube would have under different configurations/loads. My setup ...
1
vote
0answers
52 views

Applying Statistical Mechanics to Formulate Corrosion (Rusting)

I wanted to try and take my current knowledge of statistical mechanics (first quarter undergraduate course completed, beginning researcher in far from equilibrium statistical mechanics, basic ...
-9
votes
2answers
263 views

Can a sound like a sonic boom change a object like a wall? And how the light on the walls will be changed after a sound like this? [closed]

Can a sound like a sonic boom change a object like a wall? And how the light on the walls will be changed after a sound like this? .
5
votes
1answer
176 views

What is the theoretical upper limit on the rigidity of a material?

Take a perfectly rigid metal rod of length $2\ell$ and some uniform linear density. Place one end (‘south’) at $(0,-\ell)$ and the other (‘north’) at $(0, \ell)$. Over some reasonably short time ...
0
votes
0answers
16 views

What curved, transparent media exists for full-motion holograms?

Looking to project light either on, or through, but not from, a transparent medium. So I'm thinking of half a hollow sphere with a surface thickness of 1/10th the radius of sphere. A clear curved ...
0
votes
0answers
39 views

Material Evaporation in Low Pressure Condition

Are there any references for the determination of evaporation temperature of materials under low pressure condition? Specifically, I need to evaporate InP under low pressure at around 1.0 Torr which ...
3
votes
1answer
124 views

Theoretical limits to specific strength with hierarchical structures

Specific strength (measured in units of pressure/density or speed$^2$ which in MKS there is a proposal for labelling it as the Yuri (meter/second)$^2$) is defined as tensile strength divided by ...
0
votes
1answer
72 views

Drilling a Vault [closed]

Premise I think this is a Physics question, so i thought this would be the right stackexchange website to post my question. If I'm wrong, feel free to move the question in the right website. I'm not ...
1
vote
2answers
3k views

Does infrared rays pass through polarized glass?

Actually I had asked in another post that "Does infrared rays pass through active shutter glass" but someone just commented that infrared rays dont pass through polarized glass. If infrared rays ...
0
votes
0answers
39 views

Like viscoelastic polymers, why there are not storage and loss moduli for cast iron?

Viscoelastic polymers have different paths upon loading and unloading, so there is energy dissipation, so they have storage and loss moduli. Plastic behavior is also shown by cast iron: loading and ...
8
votes
4answers
11k views

Does glass get stronger the longer its under water?

I was reading the internets and I saw an image of of random facts. Yes, I know, its a humor site, but based on the image item #23 I have some questions. Does glass really get stronger the longer its ...
0
votes
2answers
49 views

Are there materials with more than two states that can be used in circuit design? [closed]

Are there atoms or materials that have 3 or more states that can be used in circuit design? Can you provide any examples of such materials, and their possible applications to circuit design? And is ...
5
votes
1answer
119 views

Superhydrophobic coating and water friction

If you were to apply super-hydrophobic coating to the hull of ships or even submarines, would you get more or less water friction? If the coating completely repels the water you could argue there ...
0
votes
1answer
30 views

Stresses in materials depend on co-ordinate system of choice, true or not?

I was studying stresses and strains and my professor told me that they depend on the co-ordinate system we choose to represent, he also said that as we rotate the co-ordinate system, shears that were ...
19
votes
2answers
3k views

Melting diamond and cool down as diamond

Is it possible to melt diamond? And if possible while let it cool will it became diamond again?
1
vote
1answer
57 views

What is difference between anisotropy and inhomogeinity of this type of composite material?

I am studying some types of composite materials having 2 phases - fibers and matrix. I have some questions and confusions. Any help is appreciated. The composite has fiber along length and I am ...
1
vote
2answers
111 views

Does induced current affect the permeability of a material?

For electromagnetic wave propagation, we can typically characterize a medium by conductivity $\sigma$, permeability $\mu$, and permittivity $\epsilon$. Consider if this material had current passing ...
1
vote
1answer
48 views

Can I tear apart a pipe with magnetostriction? And how big field should I use?

As I know, with magnetostriction we can "stretch" its unit cell. The stronger is the field, the more it expands the cell. Using alternating current in coils that induce magnetic field we can stretch ...
0
votes
1answer
54 views

Why do pores make ceramic opaque?

I want to know how a ceramic transparency is mostly affected by the pores, grain boundary, second phases etc. present inside of it, but the major contribution is due to the pores. Let's consider the ...
0
votes
0answers
110 views

Is Sapphire crystal flexible?

It is widely rumoured that the next iPhone's screen cover will be a sheet of synthetic Sapphire crystal. A video purporting to show a leaked part has emerged. The chap in the video (Marques Brownlee) ...
0
votes
0answers
21 views

What's responsible for dull or sharp sounds in a struck sintered rods?

I've sintered a number of rods from powdered oxide materials, and some of them ring clearly after being struck (not as clear as, say, a metal tube, but clear enough to hear a definite pitch), while ...
1
vote
1answer
355 views

Divergence of Cauchy Stress Tensor

On the wikipedia page for the Cauchy Momementum Equation, it's stated that the equation can be written as $$\rho \frac{D\,\textbf{v}}{D\,t} = \nabla \cdot \sigma + \textbf{f}$$ Where $\sigma$ is ...
3
votes
2answers
127 views

Is it right to cut a slot on some material before bending?

I made a suggestion to my boss to cut a thin, shallow slot on a metal sheet on the side we wanna make 90°, so that the machine could bend it. However, the outcome was "The metal broke". My boss was ...
3
votes
1answer
56 views

Why nano indentation is used to test bulk material?

I am curious why nano indentation is used? I can understand when material size goes to micros or below, conventional hardening methods can become difficult to use. However many papers say that ...
0
votes
0answers
43 views

How does quantum confinement happen in amorphous or polycrystalline materials?

You can easily find papers where they make a nanostructure (thin film, nanowire, or quantum dot) from methods (ALD, CVD, thermal/egun evaporation) that produce amorphous or polycrystalline structures ...
6
votes
3answers
235 views

Hollow gold bar

A scammer got a hollow gold bar and fills it with a combination of lead and air, with the same average density as gold. What's the simplest way of discovering the fraud? I know that x-rays will see ...
0
votes
0answers
52 views

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 ...
1
vote
2answers
116 views

What are some examples of non-Lambertian light scatters/radiators in everyday life?

What are some examples of non-Lambertian light scatters/radiators in everyday life? How to easily demonstrate their difference from Lambertian ones?
0
votes
1answer
153 views

Is there a difference between spring fatigue and plastic deformation in springs?

Is there a difference between spring fatigue and plastic deformation in springs? Plastic deformation means permanent deformation in springs caused due to stretching in springs.
187
votes
11answers
40k views

Why don't metals bond when touched together?

It is my understanding that metals are a crystal lattice of ions, held together by delocalized electrons, which move freely through the lattice (and conduct electricity, heat, etc.). If two pieces ...
0
votes
0answers
103 views

How to calculate a Mooney-Rivlin material

Well, I'm working on a fsi (fluid-solid/structure interaction) model. I've got ready the fluid part, now I need to get ready the solid part. Since I'm working with tissues, I need to use an ...