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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Why is carbon boil even necessary?
Particularly in an Electric Arc Furnace I have seen carbon boil occuring . I understand the reaction is very vital but what is it's utility? A detailed answer to this is most welcome. The internet ...
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What does time temperature specifically give us? [closed]
What is a Time Temperature curve basically? I have come across this a couple of times while dealing with heat treatment in my industry. A detailed reply to this is most welcome.
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Why is manganese steel non magnetic in as cast condition? [closed]
Is it because of some ferrite stabilizer or something?A detailed explanation to this is most welcome.
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What impact does reduction internal stress cause?
I have noted that recovery primarily reduces the internal stresses of the material.What is particularly confusing is why would that work out.A slightly detailed answer to this is most recommended.Also ...
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Why does decrease in dislocation density result in higher ductility?
Why does a decrease in dislocation density result in decrease in yield strength and increase in ductility?A slightly detailed explanation is what I am looking forward to.
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Unknown metal-piece connected to the case of an iPod Nano 2
I disassembled an iPod Nano 2 yesterday and was surprised to find a round brass-coloured plate glued to the back. I didn't find any mention of it at the teardown over at ifixit.com, as they didn't cut ...
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What is meant by soaking time in heat treatment?
After heating at 950°C and holding the temperature for 3 hours there is a soaking time that is provided for 12 hours. What is the soaking time being referred to here? A detailed reply to this will be ...
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A question on how heat treatment is done in bogies
During heat treatment of metals I find that Normalizing is done in railway bogies and tempering is done following normalizing only for the CP top and bottom. Following the tempering process quenching ...
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What is the characterising difference between a riser and a runner?
The image given below shows a bolster with a series of riser and runner. What I really do not understand is which is the riser and which is the runner. Also a detailed explanation to why multiple ...
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How to evenly heat stainless type 304 steel bar to approximately 200F?
I need to heat stainless bar stock prior to bending in a forming machine. I would like to reach approximately 200 degrees F.
The material is stainless type 304/304L, 3/16" thick.
We are heating ...
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Can Rotary Friction Welding be used to join metals and ceramics?
Is Rotary Friction Welding a good method to join cylinders of a metal (such as Ti alloy) and a ceramic (such as SiC).
I know that Diffusion bonding can be used in such cases. However, it has its own ...
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What is the effect of Aluminium nitriding in steel?
"The most significant effect of AlN in steel is on grain size control, which directly influences hardenability, hot ductility, texture development, and mechanical properties."I have read ...
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Fluid energy mills with powdered reactive metals
Can fluid energy mills manufacture spherical powdered metal of size ~5 micrometers in cases where the metal is quite reactive, like with lithium and aluminum, if the fluid used is a non reactive gas ...
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Question about a particular statement on plastic deformation of single crystals
"...the wider the dislocation, the lower is the elastic energy of the crystal because the atomic spacing in the slip direction is closer to its equilibrium spacing."
What has elastic energy ...
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Doubt in triaxial stress state in a notched specimen
In the book titled "Mechanical Metallurgy" written by G.E.Dieter I am having problems to understand why a notch in a material would mean a triaxial state of stress.I do well understand that ...
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Why does corrosion take place at certain stressed regions?
Why does certain parts of metal show more corrosion at the place where there is high dislocation density in comparison to the place where the dislocation density is less? I do sincerely feel that this ...
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Is it possible to determine how the steel was made, having its microstructure (for example, to distinguish forging from rolled products)?
How do you think the steel in these images was made?
Example1
(https://i.stack.imgur.com/oZLRM.jpg)
Example 2
(https://i.stack.imgur.com/jrDE7.jpg)
Example 3
(https://i.stack.imgur.com/fpl2d.jpg)
...
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Tempering 1095 steel
I have some laser-cut filing templates, about the size of a business card, made from 3mm-thick 1095 carbon steel. These parts will be used to guide a round metal file when filing odd shaped holes in ...
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Why do you need helicoil if you can just use a tap?
I'm new to thread repairs and I was just wondering when using a helicoil, why does the helicoil need to be inserted if you have already tapped the new threads into a hole? Can't you just put a bolt in ...
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Is thermal conductivity a property that affects the use of an alloy in high-temperature applications?
I'm interested in the effect of thermal conductivity on the choice of materials used for high temperature applications such as turbines.
For the particular case of Nickel-Chromium alloys (such as René ...
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Finding fraction of liquid and solid from isomorphous alloy phase diagram
if alpha of 82% B and liquid of 57% B are in equilibrium in an alloy of 73% B,the fraction of liquid is?
I know formula for it, but confused in finding property.
Any help will be of great use & ...
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Can a threaded fastener stretch so much it can be miss-read as a different pitch?
Can a threaded stud of mild steel, size 5/8"-11 over a threaded portion of 1.25" stretch so much over time that it reads 5/8"-13?
Unthreaded portion of the stud reads .625-630" in ...
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Where to find a list of hard low melting point alloys?
Im looking for alloys that have a melting point lower than 600°C and as high as possible hardness. Is there a search engine I could use to find those alloys with their physical properties?
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What alloy am I making (Al-Bi)
I have been melting aluminum in a DIY furnace for a few months in order to make lost wax casts. I was thinking that since bismuth has a much lower melting point than aluminum, that I could add a small ...
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Purpose of a GD-Zn alloy
Here are screenshots of the data-sheets of two separate products for a reference. They both are nickel plated, used for coupling nuts. The former is shielded, the latter is not, I wonder if this is ...
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I have a small piece of stainless steel that I need to remove 1-2mm of material. The hardness is 200. What type of file do I need to get?
This is a part of a mounting system for an Olight pistol flashlight. The universal adapter that they include isn't so universal when it comes to a Canik handgun. I've talked to the people at Olight ...
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What's the benefit of copper plating paper clips?
(Sorry, not an engineer or student, just looking for the most metallurgically relevant stack.)
Recently I was in someone's office and, while playing with their paper clips, it occurred to me that ...
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Is it possible to silver solder a reliable grounding connection to a stainless steel ultrasonic cleaner tank?
My ultrasonic cleaner has a stainless steel tank with a threaded grounding stud for fastening a mains earth wire. I tried to tighten nut that fastens the ground terminal to the stud, but the stud ...
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How to rule-out if there's lead in a pipe's alloy?
I have a 2" diameter, 6" long pipe that I believe to be steel and want to use IF it is, heck I want to use it if it's OK to handle (ie not lead, arsenic etc..guess I can only rule-out so ...
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Can the US realistically mine and produce all Rare Earth Elements, without relying on China? [closed]
Why exactly isn't the US mining and producing its own rare earth metals (REEs)? I'm baffled by the mixed messages below. Because China uniquely possesses some REEs? US safeguards against pollution ...
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Is inverse hall-petch relation valid crystals larger than nanocrystalline?
The image shown here is of ceramics, where they varied the grain size and measured the strength. For example, let's take Al2O3. There we observed that strength first increased from 3 μm to 95 μm. But ...
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Non-toxic material for deformable wire/rod without work hardening
I am looking for a non-toxic material for a wire/rod that allows room temperature deformations without work hardening.
Example uses are semi-rigid cables that one can bend and that hold their shape ...
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Why is a mold required in isostatic pressing after performing Sintering
After an a object is formed through direct laser sintering, as a post-processing procedure the object is sent for hot-isostatic pressing, In hot isostatic pressing the sintered object is placed in a ...
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How to increase blast furnace top gas temperature?
Why does blast furnace (in Iron & Steel works) top gas temperature stays low and what are the fixes for that to increase without using a burner?
The top gas temperature goes below 80 degrees (...
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Is there any way to improve the strength of simple at-home aluminum/copper/brass castings (sand-casting hammers)
I'm just getting-into melting-down cans to make aluminum-based slingshots, hammers and the like. In my ignorance I didn't realize that copper/brass were also things that I could process which has ...
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Precipitation Hardening
Please explain the meaning of this statement with close reference to Precipitation hardening,"The relative rates of nucleation and growth are controlled by temperature. The size and dispersion of the ...
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(moulded) cast properties of the untreated surface
While my research about the untreated surface of moulded cast I read that the properties such as tensile strength, 0,2% proof stress and so on are different (much smaller) from the properties you can ...
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Effect of annealing on the defects
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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Is it possible to cast copper around another metal
So i have seen these super conductor rods around (which appear to be copper around titanium/niobium).
Now I am wondering (for a maker usecase) if its possible to create something similar by for ...
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Electric Current Based Shape-Memory Alloy
Would it be possible to create a piece of metal, made out of an alloy or combination of alloys, that undergoes a shape-memory-esque change in structure in reaction to an electric current? Could it ...
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Fastening rotating surfaces
This is probably very well explained but I'm lacking the terminology knowledge and that's keeping me from finding the information I need.
I have a frame to which I need to attach a weight carrying ...
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How to produce aluminium powder by E. J. Hall method
I have watched videos on YouTube producing Aluminum powder by mechanical methods. Like this one. It uses Aluminum foil and coffee grinder:
There are similar videos which use the same basic method but ...
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Why do Blast Furnace flue dust generates high rates of Zn (Zinc)?
The Blast Furnace flue dust contains high rates of Zn (Zinc). I'd like to know the reason behind this. The chemical reaction of Zn inside blast furnace dust. Why it's rates becoming high?
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How do old wind turbine towers pickup magnetism overtime?
I was conducting some robotics tests on a old wind turbine today, and noticed strong magnetic fields around the steel tower. This magnetic field does not exist on other modern wind turbines at the ...
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When were the japanese yellow/white/blue/silver paper steels introduced?
The steel series called kigami/shirogami (yellow/white paper steel, high purity carbon steels in different grades), aogami (blue paper steel, a tungsten alloyed tool steel series), aogami super (a ...
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Steel Worm/Steel Wheel vs Steel Worm/Bronze Wheel
I have a question regarding worm drives, specifically double-enveloping types:
Do steel worm/steel wheel combinations last longer than steel worm/bronze wheel or steel worm/brass wheel combinations? ...
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Engineering standards or testing standards for hot punched metal holes for rolled steel
So, I have a problem with fatigue cracking originating from hot punched holes. From failure forensic reviews, it seems like surface conditions contributed to some of the failures, especially where ...
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What are equations related to the compaction of composite metal powders?
Say I am trying to create a metal composite and have a mixture of 3 different metal powders each with varying weight %'s. I'm going to compact them into the shape of a ring by applying a force P. The ...
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Phase prediction by cct diagram
Can someone please help in finding out the phase proportion of each phase w.r.t time , cooling rate and temperature by using (mathematical model to predict phases from given cct diagram)
Leblond ...
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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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