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.
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Zero Stiffness Matrix
Consider a material pressure cylinder that is considered 'broken', it has a stiffness matrix of zero, at time t = 0. Now assume that a gas was inside that cylinder, and initially offered no pressure ...
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How to Improve Adhesion of Velcro to Plastic Suction Cups in Hot Climates
I am currently facing an issue with a product where Velcro is attached to plastic suction cups using adhesive. The Velcro tends to detach from the suction cups, especially in hot climates. Here are ...
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Janka hardness of Carbon Fiber
I know that Janka hardness is a measurement used for wood. However since I want to build a guitar made of several materials I got curious whether anyone has ever used the Janka test to determine the ...
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How could predict the affect the of adding another element to alloy in the terms of thermal conductivity and material wear resistance?
I'm interested in the effect thermal conductivity affect and material wear resistance by adding different element to an already high thermal conductivity like GRCop-42.
My main interest are to the ...
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Making Silicone Rubber Surface Conductive
Hey Engineering Community, a physicist this side.
I am tinkering on a project where I need a local deformation of the thin sheet(0.2mm thickness, 25cm*20cm dimension); pressing on the surface from one ...
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What is the formula to define the flexural strength of an upright cylinder?
I have been making cylindrical concrete coasters and, for fun, have been seeing if my friend's can snap them. Every subsequent mix design I'll change the mix itself or the dimensions of the geometry ...
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What is the maximum load for lateral loading of a screw?
I want to build the following swing for my grandkids:
So I reckon that there will be a lateral loading on the countersunk bolt (shown in red), I would like to know what is the maximum load (in kg) ...
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When running a consolidation test (astm D2435) what is considered a small enough amount of consolidation to move to the next load?
I have been reading my text book and the astm for lab and it talks about the material finishing consolidation (usually 24 hours per load. In the test method it does not show an acceptable amount to ...
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I was solving fluctuating load problems and the word "static" confused me
Here's a snippet of the question that was asked a couple of years ago in university exam:
A cantilever beam made of cold rolled steel for which ultimate tensile strength =540 MPa and Yield tensile ...
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Seeking Advice: Improving Resin Application in Honeycomb Lamination for a Sustainable Project
I am trying to laminate a honeycomb structure with a fiberglass and resin reinforcement. However, I have problems because a large amount of resin falls through the holes of the honeycomb and the final ...
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How do I predict electrical mean free path in nanostructures
How does one roughly predict the mean free path for electrical conduction in a nanostructure at different temperatures and under different electrical conditions such as different voltages and ...
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Which aluminum alloy is used in cheap commercial load cells?
I am planning to simulate a load cell in CAD and was wondering which aluminum alloy are cheap commercial load cells made of? I noticed there is no huge difference between the common aluminum alloys in ...
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Mechanical fasteners for HDPE pipe and sheet?
I need to fasten pieces of HDPE together but I’ve heard gluing HDPE is difficult.
I've bought sheets and pipes to make a feeder for a tortoise.
I will be using the sheets for covers for the pipes.
The ...
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How does a church built from stones survive 70 years under water?
Following the recent news about the Sau reservoir in Spain, the draught revealed an 11-century stone church which has been under water for 70 years since 1962 when the reservoir was built.
How is it ...
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DLC wear resistance
I read that a thickness of one micrometer of DLC coating (which, if I understood correctly, shows similar properties to diamond), increases the lifespan of an item plated with it from a week to more ...
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What Manufacturing Process Is Needed To Stretch Vinyl Material Around A Cushion With Complex Curves While Not Creasing The Vinyl?
What manufacturing process is needed to stretch vinyl material around a cushion with complex curves, while not creasing the vinyl? The accompanying image exhibits a cushion that is a result of the ...
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Why are direct stresses at crack surface non-zero, but shear stresses are zero?
I'm studying ceramics, more specifically, modelling failure intensity under compression.
Apparently, the shear stresses at crack surfaces are 0 because they are a free surface. However I don't see how ...
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Grade C surface plate
Surface plates come in three grades: AA, A and B. The AA grade has the best flatness, while grades A and B have respectively 2 and 4 times less accuracy. Grade B is still much flatter than normal ...
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Optical table without holes
Most optical tables have holes. Are there also optical tables without holes? Or do these things have a different name?
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Heat press for low density polyethylene sheets
I want to create a double layer sheet with custom internal channels (created with CAD or similar software) out of two low-density-polyethylene sheets, similar to those used as greenhouse cover.
Is ...
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British Standard Steel BS5S82 propagation properties
I am looking for propagation data for the BS5S82 material (case hardened). I checked in MMPDS and ESDU but to no avail. does anyone know where I can find this data? Or at least similar materials in ...
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Will petroleum jelly degrade silicone elastomer?
I have gotten conflicting information on this question. If I put a bit (1/4 of a cc) of vaseline on a silicone elastomer part and then apply gentle pressure for hours will this degrade the elastomer? ...
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Manufacture of High Temperature Superconductor Circuit Trace
How would you go about making circuit traces out of high temperature superconductor (HTS)? Low temp superconductor traces have been made with pure tin, lead-tin, etc. But those materials are much ...
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Why marine steel is not always used in cooking applications
What are the main reasons why marine steel such as 1.4404 (316L) grade is not solely used in cooking and kitchen applications? Other than cost possibly? Why other grades such as 1.4301 (304) are so ...
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What is fracture toughness and how is it different from the strength of a material?
Strength is just the amount of force that an object can take before breaking, so what is fracture toughness?
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What's the difference between ductility and stiffness?
As far as I understand they both relate to the amount of deformation based on a given amount of stress.
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Can someone help explain the difference between strength and stiffness?
I just can't seem to get it through my head and I don't understand the difference. As far as I can understand, strength is a materials resistance to permanent fracture while stiffness would be ...
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What substances have the lowest dielectric strength (volts/meter)?
All the tables of dielectric strength I can find are lists of materials that engineers use as practical insulators, and air is usually the least insulating thing on the list.
Where can I find a more ...
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Single Photon/Electron Emitter
Is it possible to buy single photon/electron emitter in market for experimental purposes? If yes, can you please guide me where and how?
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Belt conveyor roller spring
I wanted to know if anyone could help in this area.
I want to create an inclined conveyor belt where, when a cargo box reaches the top of the conveyor belt, the rollers sequentially move down (maybe ...
