New answers tagged materials
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Ferritic stainless ( 13 % Cr, 405, 409, etc) will be fine and cheaper than 304. Ferritic sheet metal was unusual decades ago, but uses in home appliances, auto exhaust, etc. has made sheet much more available. Actually if you could find an appliance junk yard, you could probable get a good deal on ferritic sheet. Some Korean appliances are 304 but most all ...
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Use an expanding mandrel, but you probably can't make one). What you could make is what you would describe as conical shaft collars. It grips, is self-centering, and handles variation in bobbin hole diameter.
You can can use plastic, wood or metal, but wood cones seem easiest to just buy off the shelf.
The ideal setup is to have an interrupted shaft with ...
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Don't forget to maintain the temperature while carrying out the test. The material will behave differently when subjected to impacts on different temperatures.
Also, if the part you are experimenting on is the outside surface in contact with the air, then also don't forget to put on the necessary paint or any other surface coating that is originally used on ...
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I used a different search engine and may have found something useful.
"When cold worked brass is progressively heated, the first effect, at about 250ºC, is for the internal stresses to be relieved. This prevents stress corrosion cracking subsequently occurring and also minimises the amount of distortion which may occur during machining. This low ...
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The alloy makes a difference. If it is essentially copper and zinc like 70:30 (cartridge brass, or admiralty if you put in one pre-cent tin) or lower amounts of zinc: Nothing much happens with the phases. Hard to guess why he thinks there is segration or residual stresses after a slow cool from 400 C. Actually a water quench would give a solution anneal, ...
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A suggestion here:
"Annealing is often confused with Tempering. Both can be considered forms of Heat Treatment, but, with the risk of oversimplifying matters – Tempering takes the metal to a lower temperature and tends to harden metals, Annealing is a shorter, hotter process and softens them.1
We don’t want to harden the metal any more than it already ...
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Assume your initial concentrations are in kg/100 kg (wt%).
Find the initial amounts. Take a basis of 100 kg of total material. This gives you the initial masses $m_j$ of C, Cr, and Fe in your sample.
Prepare to do the chemical reaction. Convert the initial masses $m_j$ to initial moles $n_j$ using the molar mass $M_j$ with $n_j = m_j/M_j$.
Determine which ...
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Exterior doors Have to be able to resist elements, be fire-rated (usually 20 minutes, but it could vary depending on type and location), and tolerate a high frequency of traffic and abuse of getting banged by large items, furnuture and appliances pushed through them.
Traditionally they were made solid-core from
Alder.
Poplar.
Cedar.
Rustica Red Oak.
Cherry.
...
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TL;DR: you need to prioritize which behaviour is important and scale the load to investigate this behavior. It is very difficult to scale the load and expect to obtain the full behaviour of the structure.
IMHO it is very difficult to scale the load and expect to obtain the full behaviour of the structure. Different loading conditions have different ...
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You are asking the wrong question. You want to know if there is Cr depletion ( reduced concentration) near the Cr carbides which have effectively removed Cr from solution. There are corrosion tests to evaluate Cr depletion, known as sensitization. It can be remedied with thermal homogenization; stabilization. Much more a concern with austenitics than your ...
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The vibrating membrane has a fundamental resonant frequency at which it becomes acoustically transparent that has a wavelength approximately equal to the diameter of the membrane. Increasing the diameter of the membrane will lower the cutoff frequency of the membrane so it is closer to the sound spectrum of human speech. In addition, the radiation resistance ...
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Either by an electron microprobe or by small-area xray diffraction.
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Some hearing aids have a biult in microphone and have adjustable angle of recption and or can transmit sound to un external speaker.
My hearing aids self agjust when i wear my pilot's head sets. while still receiving calls from my phone in my bag.
In your communty many share the same issue, try to find out what they do.
It can even effect your cognitive ...
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Ignoring the fuel source for the furnace (such as vanadium in fuel oils causing rapid oxidation); What do you want the answer to be? For minimum stress as I expect a roof to be , ferritic like 430 or 446 should be lower cost. Otherwise any of the "18-8" types like 304 (HF as a casting) would be good. I would avoid 316 , 317 because of possible ...
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Most grades of stainless steel can handle 850 degrees without problem. Even the cheap ones such as 304. Although at that temperature it will be glowing bright red. It will discolor and some degradation will occur over time. Especially if it is exposed to abrasive particulate exhaust, or if it's stressed due to thermal cycling. The solution for this is ...
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The following presumes a system at uniform temperature and pressure throughout.
What do we mean when we say "uniform composition"?
We mean that the composition averaged over a certain spatial volume of the substance remains the same moving through any location in the substance. The spatial volume may be the size of atom or molecule in a pure ...
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This might change depending of what discipline you are investigating but:
homogeneous: refers to a material that you cannot distinguish different phases in it. Usually it refers to the density properties, and it's an indicator that the density is uniform when you look at it at various scales (from m to sub mm).
(some etymology: the word comes from the ...
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