Materials Definition and 919 Threads

My AQA Year 12 physics textbook shows the following graph shown below Then it says: "For a rubber band, the change of length during unloading is greater than during loading for a given change in tension." I don't understand this. In the graph below, it looks to me that for a certain change in...

As per the title, I am unable to understand the relationship between relative permeability and frequency losses of some materials. Considering metals in powder form such as (mpp, sendust and high flux) and metglas (amorphous). Why does the density also increase in powders (mpp, sendust, high...

I am studying to get a BS in Materials Engineering. I am learning a ton of useful skills (MATLAB, spectroscopy, materials testing), but I miss the theory in the math / physics classes I took during my first couple of years. I don't know if I would like physics or math more, I like them both. I...

Bridge rubber bearing, is there a better substitute than rubber?

Does anyone know if it is possible to build a vacuum that move bean like material from one spot to another without damaging the beans? From talking with others, I would need something that would create negative air pressure for the suction but at the same time create positive air pressure to...

I am looking for career advice, including good entry points into industry. I have background in materials engineering and masters in physics. PhD in scanning tunneling microscopy so I have expertise in (ultrahigh) vacuum systems, cryogenics as far as instrumentation is concerned. I have...

I don't know much about the theory behind superconductivity and how exactly material scientists are able to create new materials so if this is a stupid question I do apologize in advance. While looking though a list of high temperature conductors I noticed that cuprates are composed of oxygen...

If I had two different materials between two oppositely charged plates, would the total dielectric strength just be an average of both dielectric constants with respect to each of their thicknesses? Or is it more complicated than that? Material A is in full contact with one plate and material...

Hi For a personal project, where can I find the free carrier density and the electron momentum relaxation time of various substances (i.e. Carbon etc .....). Is there a book or something ? Thanks. Adrian

In textbooks, are words such as 'metallic', 'metal', etc indicating to the person doing the problem that the material in question is a conductor? This one problem said 'metallic' and the answers were as if it were a conductor with the electric field between 2 concentric hollow spheres being 0...

I would love to find a materials book that is comparable to Taylor's Classical Mechanics. Taylor's book is well written with good problem sets, and it's designed for undergraduates. I also like that it burrows into one subject for 300 pages instead of being a general textbook with 2000 pages.

Hello, I'm a materials engineering undergraduate student. I would love to combine math and materials, what fields will allow me to combine these two?

Hi I just want to know the difference between Griv-Ex and G10. How long can they last and what speed up the degradation? eg UV, heat etc. thanks

https://phys.org/news/2024-01-cobalt-free-batteries-power-cars.html https://pubs.acs.org/doi/10.1021/acscentsci.3c01478 Co is a critical mineral with a vulnerable supply chain. Ideally, it would be a great benefit to reduce it's need and consumption. The authors state that they...

Residence time distribution- the time an entering particle spends in a system before it leaves. The residence time of molecules in a system is measured using tracers. The response for a system is recorded for some type of perturbation. Consider $$ A+B \rightarrow C $$ and suppose we want to...

https://www.caltech.edu/about/news/some-alloys-dont-change-size-when-heated-we-now-know-why ...

Hello everyone, I am looking for a material with the following characteristics: - It must be machinable - be as thermally insulating as possible, and resistant to a temperature of at least 100°C - transparent to near-infrared light (~1µm wavelength) - relatively resistant to deformation, for...

Photochromic lenses are common in glasses, they stay transparent indoor, but get darken when exposed to sunlight. How does it work ?

Can you recommend me a source to self study computational materials science? I am currently doing an internship and want to study in my spare time for materials science. I will take a course named computational methods in materials science but I want to learn it earlier than that but I can't...

Wooooo! It's a 5-level backsplit. Wife and I will be in back/basement, kids and grandkids will be in front/2nd floor. So, the first thing we're going to do is build a wall between the upper flat and the lower flat - where the railing is. The entrance to the left wll become a door. So, they...

What is/are the electric conductive material(s) which has/have the least heat/thermal conductive?

Hello, I want to model a thermal battery based on phase change materials (PCM). It is a plate heat exchanger immersed in a PCM bath. The diagram is given in the attached file. I want to determine the temperature at each moment and from everywhere in the battery. The hypotheses are the...

Hello Please help me. I'm not a chemistry student and I don't have a chemistry-related course, so please explain in a very simple way. Thank you. I have a composite composition that I only have the weight percentage of atoms and I need to calculate the density so that I can check the properties...

Hi, i'm struggling with that problem , i need to find the distance that point N went down.My way of thinking is that the structure is twice not statically determined because of the beam MN and beacuse of the left support which is also unnecessary in order for equilibrium. My 2 equations of...

Astronauts heading towards Mars (and hopefully return) will need protection against the harmful effects of gamma rays in space for this long trip. Apparently, much shorter trips have not caused enough bodily harm to be of much concern. However, a 6-month or longer trip might be a real problem. I...

https://physics.aps.org/articles/v15/147 That looks pretty cool. If more artists find out about it it might catch on.

This is a project I gave myself at work, really just to improve things. It didn't come from above but from myself. However I went the route of biological and computer sciences not engineering. Without going into excruciating detail essentially a plastic "tube" will be going into an oil well...

A family member shared an article about thermovoltaics being developed at MIT with support from National Renewable Energy Lab (NREL). A new heat engine with no moving parts is as efficient as a steam turbine https://news.mit.edu/2022/thermal-heat-engine-0413 The article mentions that the...

Does it have any career opportunities outside of academia? Metallurgical engineering is easily applicable and you can find jobs with it anywhere. But about nanoengineering bachelor's degree, what kind of jobs can I find?

It's been stated that the index of refraction of materials varies with frequency throughout the EM spectrum. What are the index of refraction for various materials in the radio frequency?

Hello everybody , In my research study, i am focusing the interprete the effect of solvent on opticals propertie of carbazole based hole transporting materials ,In order to dissolve this materials in different Concentration of solvents ; I have been using Toluene , chlorobenzene and...

I think the answer is that the elastic potential energy will be a 1/16th of the original value. This is my reasoning: 1) If the diameter doubles, the cross sectional area is 4 times the original value. (from A= πr2). 2) F= stress/area. Force (load is the same). If cross sectional area...

I'm trying to figure out the specific grade/code of Brass or Cast Iron used for Worm Wheels.

I need materials to study pretty good privacy.I need how authentication and confidentiality is done explanations with a block diagram. I picked up a keyword “pretty good privacy” “authentication” “confidentiality” I searched the zlibrary website for text search. Downloaded lots of books, but...

I'm currently doing an experiment with magnetic levitation but I don't know if my independent variable will even affect my results at all. I am planning on building a rail of magnets and levitating a type 2 superconductor on it. I wanted to change the material surrounding the rail of magnets...

Summary:: Torsional stress on freely spinning shaft? Hey guys, I’m having some confusion with a certain section of the “Torsion” chapter in my mechanics of materials book: “power transmission”. Please see the problem below. This is very easy to SOLVE (basically plug and chug with the...

Whats its thermal conductivity compared to copper? (as in x times worse than copper) also, How electrically insulate is it? I'm looking to see if i can use it to encase an entire motherboard in a giant heat sink for a future project where i want to try and cool the entire motherboard to subzero...

Hello! I am new to mechanics of materials and I am very confused about the problem below. So the shear formula is: tau = VQ/It From the book (Hibbeler) I understand that Q is "y'A', where A' is the cross-sectional area of the segment that is connected to the beam at the juncture where the...

Summary:: My college assignment brief; Write a report in which you examine and describe the differences in the elastic, magnetic, and electric hysteresis experienced by the steel, polyurethane, and concrete materials respectively. The scenario: You work as a mechanical engineering for a marine...

I am looking to learn about these topological effects or phases in solids. More specifically, I'm trying to find a set of lecture notes or a textbook or some other text that do not shy away from discussing homotopy classes and the application algebraic topology to describe these materials. I...

I was wondering if someone can explain how failure criteria work when dealing with viscoelastic materials. I'm quite new to this, so I only know how they work with brittle and ductile materials. (not in too much detail either). And now that I'm at it anyway, if possible an explanation on...

That's about it. I've been trying to do the calculation manually with Bethe-Bloche without corrections in the energy range I'm interested in (1-10 MeV) for the highest Z material with data available for validation (Uranium), but I can't get a result that agree well with the database, so I'm...

What materials would be suitable for a cylinder and piston that is thermally insulating, reasonably durable for low speeds and very slow cycle rates, and not be a carbon or silicon based polymer? I've been looking at manual lever operated espresso machines lately. Particularly ones that are...

What are the differences between both of them. Which one is more in demand and pays better overall?

Hi, there. I have not systematically learned the calculus of variations. I would like to learn it now. Are there simple materials for the purpose of learning how to do the calculation in physics? No need for deeper consideration in mathematics. Is Mathematical methods for physicists by Arfken...

Hello. I am looking for some materials related to the ensemble average. Specifically, suppose there is a function ##A(x)## satisfying a Gaussian white noise $$\left < A(x)A(x') \right > =A_0^2\exp \left ( -\frac 1 {L^2}(x-x')^2\right )$$ where the average is taken over an ensemble. Now I need...

Are there any good textbooks about waves? Like Pain or French except written competently, devoid of mistakes and logical even axiomatic. Ambitious with strong math. Can be old. We were recommended to read Pain but that book is a joke and French is just a simplified version thereof. Problems are...

For my end-of-semester project, I was tasked to investigate an aspect of magnetism/magnetic materials, to do some literature review on the topic, and code a mathematical model and display my results graphically. I couldn't find anything I wanted to do, so I asked the professor to assign me a...

I have read a document where it says that composite materials are expensive to recycle but did not explain why. However, I am searching and find only a few papers and answers.

I'm new to composite materials. I've studied mechanical engineering but I am actually usually involved in hydrodynamics (in which I've done my masters). However for a project we do fluid structure interaction with composites, and as these things go, you cannot get away with the 'black box'...