Questions tagged [metallurgy]
Metallurgy is the science of the production and the processing of different metals and other metallurgic usable elements.
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Kfactor for laminated steel plates rolling
I need to make a flat pattern for a cylinder made from a steel plate 44mm thick laminated with explosion cladding stainless steel plate of 8mm total plate thickness is 52mm.
How I usually work is ...
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How to find phase proportion at equilibrium - from iron-carbon diagram - Leblond
{Equilibrium proportion P, this is the proportion which is reached at a constant temperature after an infinitely long time:P is also the austenite proportion in the case of extremely slow heating. It ...
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What actually cause quench cracking, non-uniform cooling or rapid cooling?
It’s well known that quenching most alloyed steels starting from AISI 4140 to high speed steels in water, brine , or sometimes oil will cause cracking and distortions.
In industry, oil quenching is ...
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What is the strongest and lightest material?
I have heard titanium is the strongest and the lightest material. It is used for my glasses' frame. Is it true that it is the strongest and the lightest as well?
Strongest, the biggest forces can it ...
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Can high alloy tool steels be quenched in brine?
It is will known that most of tool steels are quenched in oil to prevent cracking and distortion which appears when quenching in water due to non-uniform cooling caused by formation of insulating ...
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Are there is vanadium-free high speed steels?
Vanadium is present in all high speed steel grades. Unfortunately vanadium is not only very expensive but is also a well known cytotoxic metal. Some workers get a severe persistent cough lasting for ...
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which type of casting will give higher cooling rate, casting in thin water-cooled copper mold or casting in thick copper die?
It is will known that increasing cooling of a metal casting will lead to finer micro-structure which mean higher mechanical properties.
If I have 2 molds one is thick copper die ,& second is just ...
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What's the Difference Between LT and T Directions?
What is the difference between LT and T directions in MMPDS (formerly MIL-Handbook 5)?
I hand understood that forming metal orients its grains, destroying the isotropic nature of 'pure metal' and ...
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Carbon Phase Diagram vs. TTT diagram
A "Carbon Phase Diagram" has an upper and a lower transformation temperatures. It was my understanding that once a steel had cooled below the lower transformation temp (1333 deg F) that the austenite ...
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What is the difference between work hardening and strain hardening?
I have come across the definition somewhere,"Work hardening, also known as strain hardening, is the strengthening of a metal or polymer by plastic deformation. This strengthening occurs because of ...
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Galvanized Steel (Zinc Plated Steel) vs Stainless Steel
Zinc Plating is known for its ability to prevent most corrosion, and it is done by just dipping a metal in hot pool of zinc and letting it cooldown. Meanwhile, stainless steel, an alloy that is ...
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Why are vacancies in solids called as equilibrium defects?
My professor, when discussing about Random Walk model during diffusion in metals said that "Vacancies are equilibrium defects but dislocations are not". I could not understand why. Why is it so?
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What is the most corrosion resistant 55HRC stainless steel?
55 HRC is a very high hardness, even for steels.
Ideally the corrosion resistance of the steel would have to match AISI 316L or be even better.
Qenched stainless steel can go to 55HRC. Even to 65 ...
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Which materials we can use for storing liquid nitrogen?
What are the materials we can use for the long-term storage of 30~liters of liquid nitrogen with composition and grade, along with the thickness of the sheet and storage capacity? Can we use any ...
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Is it practical to make a solar furnace for small scale metal production?
Solar furnaces using mirrors to concentrate sunlight on a small area do not produce much power - perhaps 1kW per square metre of mirror - but can reach very high temperatures. From the earliest ...
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Arc welder? Cheap welding device for chainmail/chainmail jewelry
I'm hoping this is the correct StackExchange for this question/request for advice.
I'm looking to buy a welder to introduce me a little to welding, my main use-case right now is the hobby projects I ...
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Where does one go to produce custom metal objects?
I am wanting to produce custom mass plates for a project, very similar to those found in gyms. Here's a rough idea of what each one should look like:
This is essentially identical to mass plates one ...
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Best way to manufacture stainless steel apparatus?
Shown in the images below I have designed a small stainless steel apparatus with accompanying hollow metal cylinders ontop.
I'm looking into larger quantity production and simply CNC'ing these would ...
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What is strain hardening exponent?
Hardening leads to a material being more brittle.However I can't understand what is strain hardening or strain hardening exponent.Please explain why hardening leads to brittleness also in this answer ...
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38CrNiMoAlA: Does it even exist?
I have some plungers made of 38CrNiMoAlA. Their required hardness to be achieved via quenching/tempering is 51 HRC. I've scoured our technical order for heat treatment of steel alloys but the material ...
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What is the purpose of grid-like details on engine blocks?
It is common to find this kind of detailing and patterning on engine blocks and related parts. Older engine blocks display much more flatter and simple geometry and this kind of mold work must come ...
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What does it mean by "loops and troughs"? [closed]
Actually, I've asked this question in "English Language & Usage" but someone told me ask it here!
What does it mean by "loops and troughs" in:
"Source has acquired a pattern of loops and troughs."...
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How to bend copper heat pipes?
I have purchased these copper heat-pipes; however, I am wondering how to bend them without kinking them or cutting them open due to pressure on weak points/bends.
These are flat copper heat pipes, so ...
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Proper metal for turning/milling a ball-peen hammer
I've got a simple question here.
What material should hammer's head be made of? We're talking about medium sized ball-peen hammer, used for riveting brass, copper, aluminum and steel rivets. I have ...
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What material should I use to store molten metal?
I'm performing an experiment based on slag corrosion behavior of the refractory material. I need to store molten metal at $\approx$ 1600-1700 K for that.
Specifically, I'm working on slag corrosion ...
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Coating gold on to sunglasses lenses?
Recently I have been trying to find out more about the process that is used to coat glasses lenses with gold. I asked about it in another forum last night and I was directed here. I initially thought ...
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Which materials can be used to make permanent casting molds for cast iron?
I am interested in comparing the different materials that can be used to make castings of cast irons, and therefore was wondering which material is commonly used/which materials can be used to make ...
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What considerations should I take when flame-hardening a wheel?
I'm currently trying to figure out whether or not we can flame-harden a steel wheel which was supplied with a lower hardness than expected. I'm worried, however, that flame-hardening can either deform ...
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Circular keyways - advantages / disadvantages?
What are the advantages and disadvantages of using circular section ("Scotch") keys, keyseats and keyways? I am not referring to Woodruff style, I am only interested in the type where the key itself ...
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Can I mig weld to my skateboard truck? How can I test if it's weldable?
I have this skateboard truck for my off-road skateboard. I want to mig weld a piece of aluminum to it to mount a motor. How would I test if it is something I can weld to with a MIG welder? I think it ...
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Electrical Resistance of molten aluminium oxide [closed]
I would like to calculate or find the electrical resistance (in ohms) of aluminium oxide at or past its melting point, for the purposes of using it as an electrolyte in a molten state.
My apologies ...
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How to create intersected conical copper coils?
I'm looking to create something like this:
But the problem with solid copper wires is it tends to spring back into it's original shape and this construction will flatten.
I've tried creating a ...
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What is the theoretical grain size in an ideal phase diagram of a metal?
We suppose thermodynamic equilibrium in a phase diagram, where cooling rates are infinitely long and diffusion in both phases can finish completely. So when we cross the solidus line and we are left ...
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Word for the tendency of one metal to rub off on another?
Is there a word for the tendency of some metals to make crayon-like marks on other metals? For example, a lead bullet makes faint marks on some steels, but not on others with a similar surface finish....
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How is this aluminum heater mounted to the stainless plate?
I'm looking for a way to mount a 1000W electric heater to a stainless base. Electric kettle heaters could fit my requirements, but I'm wondering how the Aluminium heater is mounted to the stainless ...
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What is the rated tensile strength of 2000 kcmil stranded copper conductor?
All the documentations I could find goes upto only 1000 kcmil. Please direct to a reference for larger cables.
Is there a method to extrapolate from smaller cable sizes?
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Why is the martensite to austenite transition temperature in Shape Memory Alloys so much lower than in steel?
When learning about Shape Memory Alloys (SMAs) I was told that the mechanism that allows for strain recovery in SMAs is the martensite to austenite transformation that occurs at low temperature around ...
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Copper is more conductive, so why use lead battery terminals?
Copper is around 14 times more conductive than lead according to this source. If this is the case why are car battery terminals and connectors built using Lead? I saw both types of replacement ...
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Where can I find how good given aluminum is for machining?
What kind of resource provides summary data on how given kind of aluminum yields to machining? Are there norms, or such?
Explaining:
Different kinds of metals yield to machining differently; e.g. MO-...
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Estimate the grain size after grain growth
An uncold-worked brass specimen of average grain size 0.009 mm is heated to 600 degrees Celsius for 1000s, what is the average grain size based on this graph?
How to tackle this problem? I don't know ...
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What is the highest-temp castable refractory cement available?
I very much ruined 3 $10 diamond hole saws making this ceramic insulator out of a firebrick and Ryobi drill press. Drilling out the large core took 1-2 hours and a lot of arm strength.
Therefore, I ...
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Determining the microstructure of steel after welding in modern computer software
How can the microstructure of steel after welding be determined in modern computer software?
I am aware that there are 'classic' methods of predicting microstructures like Schaeffler, DeLong or WRC ...
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Does unloading beyond yield point also affect tensile strength?
I know that with strain-hardening you increase the yield and tensile strength. So if you unload at point D, then you also have cold worked it a bit right?
So the stress-strain curve will look ...
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Theoretical strength of pure and perfect crystals are way higher than the strength of crystals with dislocation?
Apperently in the beginning of material science they theoretically calculated the strength of perfect crystals, which was way higher than the experimental strength. The difference was later ascribed ...
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Plastic deformation due to the motion of dislocations
In this picture do we speak of (microscopic) plastic deformation if the edge dislocation has moved all the way to the right and emerges out of the surface? Or if you apply shear stress and stop when ...
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How does a graph with tensile stress-strain curve and compressive stress-strain curve superimposed look like involving true stress and true strain?
If you have a graph with a tensile stress-strain curve of a typical metal or alloy and you superimpose a compressive stress-strain curve on it (from same metal or alloy), how would this look like if ...
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Why is strain also normalized to the parameters of engineering strain?
I get that you normalize stress to engineering stress, so that it is independent of the cross sectional area. This means you can calculate (roughly) the stress needed to elongate the specimen to the ...
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How can dross/slag formation be reduced during aluminum recycling?
I have a furnace for aluminum recycling wherein dross formation is a major issue. It reduces the yield by about 10-12%.
I am looking for a change in process parameters or other solutions through which ...
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What material is used to hold molten iron in a furnace?
When iron is melted, I guess it has to be transported and contained. I think the container in which it is has to be able to withstand higher temperatures than what you want to melt.
According to this ...
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Why is the Poisson's ratio for isotropic 1/4 and the maximum value 1/2 (when there is no net volume change)?
It sounds logical untill I tried some thought experiments. So I must be doing something wrong. Or I am missing a fundamental aspect.
What I thought of was:
-lets say you have an orthogonal ...
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