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15

One of the key considerations is that much of the interesting mechanical behaviour doesn't occur within the bulk of the material - it occurs at the interfaces between crystals (known as grains). Grain boundary slip, rotation and growth often defines the mechanics - carbon has a tendency to block the motion of grain boundaries, which are one of the key ...


14

First, the alloy $(0.5$ to $\pu{2 g})$ should be treated by $\pu{10 mL}$ nitric acid $32\,\%.$ All metals will get dissolved, except tin and silicon, which will be transformed into insoluble dioxide $\ce{SnO2}$ or $\ce{SiO2}$. Dilute in $\pu{100 mL}$ hot water. $\ce{SiO2 + SnO2}$ will make a gelatinous precipitate, that can be eliminated by filtration. Add $\...


9

Let's consider that steel may contain $\pu{1\%}$ carbon. I know it is a bit much. Let us express this mass concentration as molar concentration for a sample of $\pu{100 g}$ of steel. Since this sample contains $\pu{99 g}$ of iron, this amount equates to $$n(\ce{Fe}) = \frac{\pu{99 g}} { \pu{56 g mol^{-1}} } = \pu{1.768 mol}$$ and $$n(\ce{C}) = \frac{\pu{1 g}...


7

Possibly, there are two extrema to account: a) the atomic radii of metal A and metal B do not differ significantly, and thus there are chances both metals blend statistically with each other. Which would be covered by the $< 15\%$-rule, a situation similar to mixing apples and oranges in one crate. b) the atomic radii differ a lot. If we assume atoms as ...


5

Elastic deformation properties like stiffness (Young's Modulus) vary very little with alloying element concentration since we are only working on the pre-yield bond strength. A pure iron, a carbon steel and a high alloy steel will only vary by about 15% in stiffness. So elastic properties will, as you suggest, be fairly invariant under small changes in alloy ...


5

Judging from the location and colour, it is most likely residue from liquid polish that was not properly rubbed/polished off. Quite a few types of liquid polish for brass turn white when they dry, and any folds and creases in the design is where they would be most likely to accumulate if the person doing the polishing is not very thorough. Depending on how ...


5

301 is the lowest alloy content of the "18-8" family. The slightly lower nickel ( compared to 304) makes the austenite less stable so when cold rolled it work hardens more than 304. It is still basically austenitic so does not become brittle at low temperatures. So it was chosen for the higher strength ( when cold worked) at all temperatures , ...


5

There are a few papers on Zinc-Platinum Systems (e.g., Ref.1 and 2, which are also sited in Ref.3), but most of them are in German. However, there were few useful data published by Johnson and Dillon in their Research and Development Report (Ref.4): $$ \bf{The \ structures \ of \ platinum-zinc \ intermetallic \ phases}\\ \begin{array}{l|l r r} \hline \text{...


3

Do you say stainless steel? Stainless steel is an alloy of $\ce{Ni, Cr, Fe}$ with other trace elements, and owes its apparent resistance to corrosion to a protective, adherent, coating of mixed chrome, nickel, and iron oxides. A large amount is probably $\ce{Cr^3+}$, which is amphoteric and will dissolve in hydroxide solution. Once the protective coating is ...


3

American Society for Metals has many publications. Temperatures below ambient are no problem for any aluminum alloys. They are commonly used for natural gas separation liquefaction exchangers and piping down to −100 °C (guess at the temp.). In the T6 condition (hardened) room temperature yield is 31000 psi; at 300 °F the short term yield is 20000 psi; 6500 ...


2

Not likely. Ammonium hydroxide will attack brass, but at high concentrations and not very fast. And worse, I don't easily find data for aluminium in concentrated $\ce{NH4OH}$, probably because it has poor resistance. I think you are stuck with mechanical options. Simplest is another carb or subsection. Drilling it out is obvious. Strangely enough, I have ...


2

If it did not melt or distort, then not much happens. 1100 series is more or less pure aluminum, different designations will permit different levels of tramp elements like silicon, iron, copper, etc. It will anneal / soften, if any cold work / strain hardening was present. Without looking it up, very high temperatures like 800 °F (427 °C) could possible ...


2

Fresenius' analytical scheme is also one possibility, although it is not as direct. More information can be found in Harvey's Analytical Chemistry 2.1 Libretext. I bring this up to highlight that even though this is a classical technique, it is still mentioned in some analytical textbooks still in active use.


2

You need to define what an "operating temperature" is, for what application. An alloy that will work perfectly fine as a structural material for your kitchen oven will fall apart if used in aerospace applications. Your best bet is to find alloys used in similar applications and argue, by analouge, that these alloys will also work with your ...


2

Interstitial compounds are typically obtained when elements such as $\ce{H},$ $\ce{B},$ $\ce{C}$ and $\ce{N}$ are located within the interstitial sites of a metallic substructure. Nonetheless, the metallic substructure is not that of the pure metallic element in most cases. For example let's consider $\ce{Nb}.$ We can dissolve some amounts of $\ce{N}$ inside ...


2

Add coin into nitric acid and sulfuric acid. Nitric should be 60% weight of the coin and sulfuric should be 1.6 times. It will dissolve in minutes. Heat it up to boil unused nitric. Add some urea to neutralize acids. Add iron fillings to remove copper. Filter and melt the copper powder. You will have pure copper. Take rest of the solution, dilute it a bit, ...


2

However, my problem is that I'm not getting clear enough peaks. The obvious thing I can think of to do is increase the number of scans or lengthen the dwell time. But I was wondering if there are other solutions other people usually do that I might be missing. I do see some papers that try to deconvolute Ru and C in the same region but my professor says that ...


1

There are several Inconels , the basic one is 600. Because the Inco and Huntington divisions are now gone or acquired ,it would be difficult to get literature . But they produced copious amounts , you may be able to find some ; I have about a 6" stack of brochures I have been too lazy to discard. American Society for Metals Handbooks should be easy to ...


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