Questions tagged [materials]
Use for questions about designing, manufacturing or synthesizing engineered materials or about the properties of specific materials. Questions concerning common construction materials, such as wood, steel or masonry do not need to use this tag; use the more specific tag instead.
203
questions with no upvoted or accepted answers
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What types of materials can be tested in a split Hopkinson pressure bar?
A split Hopkinson pressure bar can test different types of specimens, I would like to know what types of materials that are suitable to be tested with this method?
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Calculating a pull force between two pieces of plastic
I have an HDPE pin, 2 mm high, 2 mm diameter, that I impress into a flat plaque of hot HDPE. It is not hot enough to melt the pin, but still hot enough that the material will shrink 4% in 24 hours.
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Plastic hardness after machining vs molding
Should there be any difference in the hardness of a plastic material that is machined vs one that is pressed from a mold?
This question is in specific reference to vinyl record production where ...
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Why do we use the strain-controlled test for the compressive strength of concrete?
As you all now, a typical stress-strain curve for concrete under compression can be seen in any reinforced concrete design textbook. The decreasing part of the curve (post-peak) can be obtained by ...
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Will a cyclic heat load transform my martensitic steel? How fast?
I have a plunger - that I'm using for glass forming - made out of a martensitic steel. Glass is at 1000°C and since martensite is a metastable phase, should I expect the properties of my plunger to ...
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Resistance measurement for electrically conductive textile sheet
I have some rolls of coated textile I want to characterize, including some measure of how well the material conducts electricity in the plane of the textile so I can judge which type is least likely ...
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What determines the rate of electron discharge machining (EDM) for different materials?
Wire EDM makes no contact with the work piece and disregards hardness.
I am using EDM to cut different materials, and I notice a clear distinction between the rate each material gets cut. For example, ...
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2
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1
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What is the force required to puncture through a sheet of foil against an anvil?
A hardened steel contour with a sharp edge presses against plastic foil which lies on top of a hardened steel anvil plate. What would be the force required to punch through the foil?
I am familiar ...
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Book recommendation for hydrodynamics of bubbles, drops, and particles
I am wondering if someone could please recommend to me some references on the topic of hydrodynamics of bubbles, drops, and particles, preferably in the context of complex and bio fluids.
I am ...
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answer
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Mirror specification used in Solar Fresnel Collector systems
Im designing a Linear Fresnel collector system, and wanted to know what type of mirrors would be suitable for use as the reflectors. Thickness, type, coating etc. I couldnt find a manufacturer of ''...
2
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Low temperature flexible polymers
I'm working on a design project that will require a flexible component that will be operating at temperatures from $0^{\circ}$C to $-200^{\circ}$C. Are there any thermoplastic polymers that remain ...
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Constant crosshead speed or constant strain rate for comparing samples of differing thickness?
Say I have two different specimens of a material, one is 10mm thick and the other is 1mm thick. Assume that this material has properties which vary depending on the rate of deformation (I would call ...
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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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Aerogel to filter virus particles
With the hype around COVID-19 DIY technology, everyone seems to circle around the same concepts.
I'm trying to think outside the box and I was wondering:
Is it possible to controllably create an ...
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Why is it desirable to have high g value for sensing applications, while high d value is desirable for actuation in piezoelectricity?
In piezoelectric materials, two parameters are defined to construct relations between electrical and mechanical energy conversions. These parameters are the charge constant d and the charge constant g....
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