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 use a 'dogbone' shape for tensile testing specimens?
Why is that the shape of the tension test specimen a dogbone-like shape?
I know that it is so that the deformation is confined to the narrow center region and to reduce the likelihood of fracture to ...
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How does the S-N curve (or Wöhler curve) of a material change with frequency?
How a Material fatigues can be characterized by a Wöhler curve where each datapoint corresponds to a failure with the stress on the y-Axis and the number of cycles on the x-axis. An example is the ...
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Schaeffler, De Long, and WRC welding diagrams - which steels can be used?
I am working on a simple program that would help welder to count how much ferrite, austenite etc. there is in weld. I am focusing on stainless steel.
I have decided to use 3 graphs: Schaeffler, De ...
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How does the relative valency of the impurity and host metals affect solubility in a substitutional solution?
I have a book that claims:
A metal will have more of a tendency to dissolve another metal of higher valency than one of a lower valency.
I interpret this as saying that a metal with higher valency ...
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What would happen if I tempered aluminum of aeronautical use (Al 2024)?
What would happen if I tempered aluminum of aeronautical use? Being more specific, an alloy of 96% of aluminum and 4% of copper, without modifications and 2% of impurities. (Al 2024)
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How small can you get a stream of molten steel to be at low pressure?
I'm designing a crucible / extruder, and right now it has a .6mm hole to extrude from. Will this work? A chart with various metals listed would be nice.
Pictures:
Click to expand
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Can vibration break a blade? [closed]
I want to break a blade as it attempts to cut into a piece of metal.
If the metal in question was vibrating rapidly or with a significant amount of force, would the blade break in attempt to cut ...
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Densities of different phases of steel (austenite, bainite)
Steel seems to be a very complex material, not least because of the different phases and microstructures. At the moment, I'm especially interested in the bainite formation that happens when austenitic ...
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Heat treatment processes for ferrous metals
I am trying to find out information about the heat treatment processes of ferrous metals as part of a project which involves making a screwdriver. This includes:
Hardening, Annealing, Tempering, ...
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Knives that never need to be sharpened [closed]
I have a set of kitchen knives which I've owned for 18 years. These knives were sold as "never need sharpening". I assumed that to be complete nonsense at the time BUT it has proved to be true! These ...
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What is the strongest known *metallic* material which can be used on Earth?
The discovery of nanotubes and graphene has pushed the limit
of material strength high enough that building a space elevator
could be managable. But most of the new materials are created
from carbon ...
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Heating Sand/Ceramic/Refractory Material under vacuum
In a Vacuum Metallurgy (Casting), a mold needs to be heated (500 to 700 degrees) to reduce thermal shock on the metal surface. Normally, a gas fired oven is employed for such job, but in a vacuum ...
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Is it necessary to preheat an investment casting mould when working in a vacuum?
Normally, in investment casting, the mould is preheated before pouring the liquid metal in to reduce thermal shock from rapid cooling.
In a vacuum, the heat transfer due to gas convection is reduced ...
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What's the difference between annealing, curing and sintering?
All these processes sound like structural change caused by heating.
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Special Considerations for Steel Plate Marketed for Laser Cutting
A contractor working for me on a steel construction project is using a steel product they refer to as 'laser plate' which is marketed as specifically as having good performance on laser cutters. This ...
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Stainless steel corrosion resistance in seawater
Stainless steel comes in several qualities.
AISI 303 (1.4305) (Stainless Steel A1) approximately 304 but more machinable due to sulfur.
AISI 304 (1.4301) (Stainless Steel A2) comprises of 18% ...
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Is stress relieving by stretching necessary when performing a T751 heat treatment after a T651?
We have a 7075 Al pump housing that has currently undergone a T651 temper but requires a T751 treatment to alleviate stress corrosion cracking.
Is it necessary to re-stretch a 7075 aluminum part to ...
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Can you get quality welds from a multiple metal wire feed welder, or do you need separate units for steel and aluminum?
The job site requires welding both aluminum and steel (each to themselves only) for different areas of the project. The contractor has a dual purpose wire feed welder (aluminum and steel) but I am ...
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What bolts should I specify with Weathering Steel?
When using weathering steel (COR-TEN) on a project, what sort of bolts should I be using?
I have yet to see fixings made of weather steel; presumably because the way it uses a sacrificial layer to ...
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Could a gold/{second metal} crown be created that would pass the Archimedes test cost effectively?
Many people are familiar with the story of Archimedes submerging a crown in water to identify if the volume of the crown was consistent with the volume of the same amount of gold. The test was to see ...
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What made bronze the first widely used (non-ornamental) metal in human civilization?
I recall learning about the bronze age in school. Why was bronze so important to the technological development of humans? Why not some other metal?
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Can we change steel properties by application of magnetic field while quenching?
Austenite is non magnetic while $\alpha$-ferrite and pearlite are magnetic. (Magnetic properties of pearlite vary as a function of carbon content)
If a strong magnetic field is applied in a ...
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How can the alloying materials of recycled steels be separated?
As I know, a very considerable part of the currently processed steels (around half of it) is coming from recycling.
But during the steels coming into the recycling process are coming normally from ...
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How can we prevent/detect hydrogen embrittlement?
There has recently been a series of high profile bolt failures on 'The Cheesegrater' in London, which have been attributed to hydrogen embrittlement.
What can engineers do to ensure that hydrogen ...
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At what temperature do I risk altering the structure of steel?
If I have structural or tool steel that has been treated to some standard (ASTM, SAE, ISO -- e.g., for hardness) but I don't know the details of the treatment, is there a "safe" temperature below ...
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