# Tag Info

18

The go-to place for alloy information is ASM International's Alloy Phase Diagram Database (providing your institution has access). Scandium-Gold: as noted in the comment by @MaxW, you can get several atomic percent (but less than 10 at.%) Sc in Au. There exist 6 compounds across the diagram which you would want to avoid most likely. Scandium-Platinum: ...

16

Metals have several general properties in common (to some degree): Luster - metals are shiny Electrical conductivity - metals conduct electricity Thermal conductivity - metals conduct heat Ductility - metals can be drawn into wires Malleability - metals can be beaten into shapes Fusibility - metals can be melted and forged All of these properties derive ...

14

Similar to inox for inoxydable (inoxidable), it equally is a French coinage. To tune mechanical properties of iron, mixing additives leads to numerous alloys of iron. In case of rene or rené as contraction of résistant (durable) and on base of Nickel, and is example of the superalloys. This source technologie des métaux et alliages - particulièrement en ...

13

AlMg3 is not the chemical formula of the alloy, it's the product name for a wrought alloy. Its technical sheet specifies the following composition: Product name AlMg3 Class of product Al-Mg alloy for MIG/TIG welding. Corresponding standards DIN 1732, SG-AlMg3, AWS A5.10, ER 5754 Nominal composition (weight %) Al: Bal. Si: 0.4 Mg: 3 ...

12

You are labouring under a misconception about the exact meaning of the word "compound". Normally when we describe, for example, ethanol as a compound of hydrogen, oxygen and carbon we don't mean that the component elements can "leak" out of it without a chemical reaction taking place. Mercury amalgams are casually described as "compounds" but not in the ...

10

Sure. Even discounting non-equilibrium conditions, any substance which expands upon freezing will by symmetry melt under pressure, even if the pressure is caused by supporting its own weight. There's a simple example: water! A sufficiently tall self-supporting block of ice standing on a flat surface will create enough pressure at its bottom that it could ...

10

You seem to approach the separation of alloys much like the separation of water-soluble salts, probably based on the fact that both involve the liquid/solid phase diagrams, which may even look alike. This is wrong; these systems are fundamentally different. Say, you have a water solution of some well-soluble salt which you need to recrystallize. You cool it ...

10

You can combine materials in two ways: chemically and mechanically. On average, if you want to the desired physical properties to add up, you want to go mechanical way, not the chemical one. Once the reaction takes place, the there is absolutely no reason to assume the product preserves properties of both precursors. It might sometimes, but more often than ...

8

George Lai's High-Temperature Corrosion and Materials Applications (excerpts available on Google Books) is a good source. Very often for molten salts, Hastelloys are used; they're special-purpose alloys developed by Haynes International. I can't find a reference, but I believe Oak Ridge National Laboratories used Hastelloys for their molten salt reactors (...

7

Much of this answer is based on a document available from NIST at Properties of Ternary Copper-Silver Systems [originally J. Phys. Chem. Ref. Data, 6(3) 621-673 (1977)] - this has an equivalent to the diagram in the question (which is just the surface of the liquidus). Now, since you are talking about balances of solid phases, it is also worth looking at the ...

7

An alloy is purely a mixture of metals (and sometimes non-metals) which are non-chemically bonded. So yes, you could mix steel and silver to create an alloy. There would be nothing stopping you from doing this, but I cannot say whether or not it would produce any desirable results. Mixing alloys with other materials is merely creating another alloy. ...

6

Iron does not form an amalgam readily, hence the use of iron electrodes in mercury switches. Apparently, iron does form alloys with mercury under specific conditions; see http://www.madsci.org/posts/archives/2011-04/1304143502.Ch.r.html. By contrast, mercury spilled on gold (e.g. gold-alloy jewelry) soaks in immediately, discoloring the gold, and migrates ...

6

Silly answer There is no enzyme that grinds down an Airstream, but an alligator might do the job! Serious (but disappointing) answer In nature, most metals seem to exist as oxides, sulfides, carbonates, halides, etc. and not as bare metals. Consequently, there was/is probably little evolutionary benefit in tackling the bare metals. Breaking down ...

6

In case your mercury didn't come with an assay of the supplier, or has been used before, you might want to remove oxidizable metals by repeatedly dripping the mercury though diluted nitric acid and distilled water. Subsequent distillation of mercury is certainly possible (at 25 mm Hg or lower), and has been reported by E. H. Riesenfeld and W. Haase in Ber. ...

6

When alloys are made by mixing molten metals (actually an alloy only need contain one metal and at least one other compound, metal or not) the metals only need to be heated to their melting point, not all the way to their boiling point. In the example you've given, the melting point of aluminum is $\pu{660^oC}$, which is $\pu{247^oC}$ below the boiling point ...

6

It provides limited corrosion protection. I would suggest just putting oil on it; more corrosion protection and it will not obscure the surface pattern which is most all that separates Damascus steel from ordinary steels. As I remember regular "bluing" is a complex of ferocyanides ; Oxides of iron are red and black , brown rusts are hydrated oxides. I have ...

6

The melting point of the vast majority of materials increases as more pressure is applied. At https://www.researchgate.net/figure/312054885_fig1_Figure-231-Experimental-pressure-temperature-phase-diagram-of-pure-iron-a is a phase diagram showing how this variation occurs for pure iron: From https://physics.stackexchange.com/questions/184032/what-is-the-...

5

According to Uranium partitioning between liquid iron and silicate melt at high pressures: implications for uranium solubility in planetary cores The solubility of U in liquid Fe is in the range of 0.6 to 800 ppm and increases with temperature (T) and pressure (P). See also U solubility in Earth’s core which finds a solubility of 2 ppm at zero ...

5

I have a solid steel pint glass and I can tell you that it pretty much instantly heats up to the temperature of the liquid you put inside. You probably have some sort of double-wall vacuum flask, which insulates by using a vacuum between the steel. As you can see, there are two walls to the flask: an inner wall and an outer wall. The inner wall is probably ...

5

'Leak' is an imprecise term here. Amalgam itself could (and probably does) wear away with attrition, and the 'powder' would be ingested. Certainly, fillings have worked loose and been swallowed. The effect of stomach acid on amalgam is probably not negligible.

5

Wet ball milling is much more effective due to Rehbinder effect producing a disjoining pressure. Adsorption layers from surfactants that arise in microcracks significantly reduce the energy expenditure necessary to crush solid materials as a result of a decrease in their free surface energy upon contact with a medium containing substances capable of ...

5

18 kt gold is generically harder than 24 kt gold. Both the site you linked and another site agree on that. Pure gold really is quite soft, and when you add things to it, it will get harder. Now, one key to your problem with understanding the hardness of gold and its alloys is that multiple different alloys can be called "18 kt gold". Different alloys ...

4

Here you can find a phase diagram for $\ce{Si/C}$ system. It does not have zones with homogeneous non-stohiometric solids. So, there is not thermodinamically stable Si/C isomorphic alloys. However, since the liquid likely to be homogeneous, it is likely for fast cooled liquid to form amorphous alloys. Indeed, google search provides plenty of links for ...

4

For any steel with less than 0.02% carbon we should see only ferrite, and for steel with >0.02% carbon we should see only pearlite. You have got a small misunderstanding here. The maximum solubility of carbon at $723\ \mathrm{^\circ C}$ is 0.02%. At room temperature it is very low ($0.005%$ at $0\ \mathrm{^\circ C}$). Also for carbon level between 0.02 and ...

4

They certainly can. Most cases where the alloying compound is more noble this is a hazard. Nickel in Iron is a popular example, you can get corrosion acceleration on the iron by reduction happening on the Ni-surfaces. Where the alloying element is less noble you usually have superficial corrosion to begin with but in the end the resulting surface is ...

4

René means “re-born” in French, it is related to one of the alloys which was not weldable when invented, but after modification it was re-born and used in production.

4

I wasn't sure what other conditions you needed for your salt bath, yet I listed few for your convenience together with the salt bath of $\ce{KNO3/NaNO2}$ (bath 5) for comparison: $$\begin{array}{ccc} \text{Bath#} &\text{Composition} & \text{Approx. melting poing} & \text{Working temp. range} \\\hline 1 & \ce{NaCl}, \ce{KCl}, \ce{BaCl2}, \ce{... 3 Lithium might be tricky to alloy in an oxidizing atmosphere (e.g. air), and Pt might take some effort to form an alloy, because of its high m.p., which, however, is still less than than the boiling points of Bi or Sn. Other than that, there should be little trouble forming alloys. You can search on line for "phase diagram alloy components" to find the ... 3 Short answer: Yes. Long answer: Any alloy containing 'passivating' elements such as aluminum, which have the tendency to form a protective oxide as you describe, has the potential to also form the same sort of passivating oxide layer as the pure material. It's not guaranteed, though. Pure zirconium also forms a passivating oxide (\ce{ZrO2})$$^{(1)}$, so ... 3 I recommend to dissolve the copper-nickel alloy in nitric acid and determine the dissolved$\ce{Cu(II)}$by iodometric titration. Start by weighing the coin, then dissolve it by placing it in nitric acid solution (under a fume hood). Continue to boil the solution for 20 min after complete dissolution of the coin (to remove any traces of remaining$\ce{NO2}\$ ...

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