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A study undertaken by Nutting and Nuttall at the University of Leeds found that "gold is not inherently more ductile than other face-centered cubic metals", such as copper. The authors found by experimentation that "gold is considerably less ductile in tension than silver." But when beaten foil becomes very thin, other metals tend to fragment, whereas gold ...


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I remember hearing on the radio sometime ago of an experiment where a very small mass was placed on a large steel girder sticking out of a wall and a microscopic displacement was observed - I think this was in Cranfield University in the UK, but can't remember any more details about it. I would be very suprised if Hooke's Law did not work for microscopic ...


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The phenomenon you're looking at is creep, in which a metal held at a constant strain will gradually relax and so reduce the stress. This will reduce the stored strain energy. It has nothing to do with fatigue, which is the result of repeated cyclic loading, and it has nothing to do with the homogeneity of the stress field. The Wikipedia article ...


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Dead simple! Materials tear when the stress in them gets above a certain level. The stress at the tip of even a small but sharp crack is huge! So it doesn't take much extra force to cause the small crack to tear through the material. How do you tear a sheet of paper? Put a small crack in it then pull! However, I have to expand on this to clear ...


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Having previously done academic research on various aspects of knives, I agree with @MSAlters - the actual polymer you're cutting is quite tough. The practical solution is to do what professional knife-users, like butchers, carpet layers, whatever, do: run the blade through a hand-held sharpener after every few strokes. I now do this when indulging ...


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The data you quote shows that diamond is stronger than steel, but strength isn't the same as brittleness (or, indeed, stiffness). Brittleness is to do with how much energy is needed to break something, and takes into account the amount of deformation it can take as well as its strength. Steel can deform a lot before it breaks, diamond can't and so ...


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No! The two fundamental moduli are the shear modulus $G$, which is the resistance of a material to change of shape under applied forces, and the bulk modulus $K$, which is its resistance to change of volume. Young's modulus $E$ is a hybrid of the two which is only popular because it's the easiest to measure experimentally. In general: $$G=E/(2+2\nu)$$ ...


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Resistance changes with temperature The temperature coefficient of resistance, or TCR, is one of the main used parameters to characterize a resistor. The TCR defines the change in resistance as a function of the ambient temperature. The common way to express the TCR is in ppm/°C, which stands for parts per million per centigrade degree. The temperature ...


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Your test will not be measuring a single property of the test specimens, so it won't have a specific name. But we can try and draw some inferences about what you'll be measuring with these experiments, using the idealised schematic above. In it the bone has been replaced with a uniform bar, with a hole drilled through it at the halfway point. The bar is ...


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Yes, the ions carry charge. However, the substrate is grounded so that current flows to keep the substrate neutral (and to measure the implanted dose). Otherwise a potential would rapidly build up (possibly up to the accelerating potential), changing the implant profile and/or causing arcing. (As an aside, this causes some difficulties when implanting or ...


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The speed of light in a medium depends on the frequency of the electromagnetic radiation $$v(\nu) = \frac{c}{n(\nu)}$$ where $n(\nu)$ is the refractive index. In a general case, $n(\nu)$ is a complex number, and its imaginary part accounts for the absorption of the medium (i.e. if a material is not transparent at frequency $\nu$, then $\textrm{Im } n(\nu) ...


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What you and I view as transparent or opaque are only that way in relation to photons in the visible spectrum (electromagnetic wavelengths between 390 and 700 nm) - this is because electrons in the material interact with those energies. In the case of opaque materials it's a safe bet that if you use a high enough energy photon (ultra violet and beyond) you ...


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Surface tension is equivalent to an interfacial energy. They are equivalent because if you increase the area of the interface you increase the energy of the interface, so you have to do work. The work done is the surface tension of the interface times the increase in area. So we can associate a surface tension to gas-solid or liquid-solid interfaces even ...


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Can you define "side"? Are you looking for a material which changes its absorptivity in one axis only when illuminated from a different axis? I tend to doubt that even hyperboic, aka metamaterials, can demonstrate such a behavior. As you may know, there a variety of organic dyes which are used as either saturable absorbers or saturable transmitters. ...



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