What is the purpose of this texture on metal surfaces?
371347
You have good answers here but I could add that the vibrations of two plates (with and without the pattern) should differ.  The old saying "He stole my thunder" comes from (Old English?) plays.  One play used a large sheet of metal that sounded like thunder when vigorously skook.  Nobody liked the play(?) but they loved (and stole) the thunder.\n\nAlso consider that when walking on the pattern you may be less likely to slip and fall (rubber soles would conform to the pattern) and it could be a safety consideration.  I believe that the pattern would increase the effective thickness of a plate making it stiffer to resist bending.  Its use could reduce weight (and cost?) in certain applications.  The pattern would also break up reflections avoiding glare especially on vertical surfaces.  The pattern might also hold paints better than a flat sheet.  The pattern would also break up the reflection of sound reducing noise level if that was important.  Also a skid might move easier across the pattern which is a series of little hills (inclines).  Grit trapped between a skid and a smooth floor might be forced to "machine" the floor (which is why old 33rpm records shold be kept in their jackets and not stacked naked).  I'd also guess that it might be easier to bond the pattern to some surfaces (floor and walls) than smooth sheet depending on the grout.  Interesting question.
676026
Wild guess here... a dihydrate of copper chloride.\n\nSecond guess would be copper sulfate, possibly from the manufacturing process.
1165847
Depends on what you are mounting....but most likely because it is cheap and safe.\n\nIt is also often used to dehydrate specimens without collapsing their structure.
336860
Mag inspection utilizes the phenomenon of ' magnetic lines of force' to indicate flaws in metal castings or machinings.\n\nThis only works with pieces made of ' magnetic' material, such as Iron, steel. ( Stainless and aluminum will NOT work ). \n\nA fine powder of Iron Oxide is sprinkled liberally on the piece to be inspected.  A strong magnetic field is applied from a coil.  If a crack or void exists, the uniform lines of magnetic force will be ' distorted' around the flaw, making the Iron Oxide gather in that area.  The area can then be marked with a grease pen, and analyzed for quality control, rejected, or repaired.
1047332
once metal is painted, then it has to be continually touched up and repainted and becomes a costly maintenance item, and not an easy place to build a scaffold. Whereas leaving the metal bare will last and retain it's look for a very long time.
837948
Articles from the HTPAA Quarterly Publication - Tool Chest  \n\nFeatured Article on Rust Removal\nPart 1 - Electrolysis\nHome  \nElectrolytic Removal of Rust \n\nby Kevin Chamberlain, Member HTPAA ( published in Tool Chest #63, February 2002) \n\nIntroduction \n\nAt our last Tool Conference, there was a Panel Discussion dealing with the cleaning and restoration of old hand tools. This is a key concern for anyone interested in collecting old tools, since one rarely finds tools in mint condition in an original box. It is much more common to find tools showing the combined effects of correct usage, abuse, neglect and simple ageing. The primary question is: should cleaning and/or restoration be attempted at all?\n\nThe answers are conflicting; some aim to restore the tool to a brand-new appearance, eliminating all evidence of its life history. Others think any attempt at restoration will destroy the character and value of an antique tool. \n\nMost think some intervention is desirable to remedy the effects of abuse and neglect, while still retraining as much patina and character as possible. There is an important caveat - "when in doubt, do nothing". Cleaning and restoration of antique tools should be done in a careful and meditative mood - otherwise rash actions may cause loss of valuable information and/or further damage. \n\nRemoval of rust from old tools or other artefacts may or may not be a desirable goal. In some cases (museum specimens) stabilization to prevent further deterioration may be all that is necessary. Rust may be regarded as undesirable by tool users or collectors because it obscures identifying marks, causes seizure of moving parts, creates an unpleasant rough texture to the touch, stains the hands and/or the workpiece, or is simply unsightly. I believe rust removal is often justified, but the method chosen should not alter the surface in other ways and should result in a reasonably attractive surface appearance.\n\nThe electrolytic method of rust removal meets these aims very well and is also a gentle, cheap and adaptable method. Electrolysis is now being used by a wide range of artefact restorers, from tool collectors to marine archaeologists. \n\nIn this article, I mainly aim to outline the practical aspects of the electrolytic method so that members can try it for themselves. Several HTPAA members have been using the method for some years and find it very useful\n\nWhat is Rust? \nRust arises from the surface oxidation of iron or steel in the presence of atmospheric oxygen and moisture. As the rust forms, the surface of the iron is eaten away, sometimes evenly, but often deep local pitting occurs beneath wart-like protuberances. Rust occupies more volume than the iron it replaces, and so moving parts will tend to seize as they rust. \nChemically, most red rust is hydrous ferric oxide FeO(OH). If water enters this chemical structure, yellow-brown limonite may form FeO(OH).nH2O. Quite often, black iron oxides are also present usually magnetite (Fe3O4), an iron oxide which both conducts electricity and can be magnetised. The rusting process, and the conditions which promote, inhibit or stabilise it, are all important topics which are beyond the limits of the present article. \n\nMethods of Rust Removal\nRust usually binds strongly to the underlying iron or steel. Various methods have been used to remove rust. Mechanical methods include the use of emery paper, sandpaper or wire brushes (either manual or powered). More aggressive methods include sand blasting or shot blasting. Plastic bead blasting is a more recent and gentler variant. Clearly these methods will scratch the metal surface if the abrasives are harder than the metal. Wire brushes, for example, do not appear to scratch hard steel surfaces but they can be quite damaging to soft iron surfaces. \n\nGas flames are sometimes used to dislodge rust, relying on the different expansion rates of the oxides and the metal in response to heat. Simple bo
1068226
I don't know that it does in general.\n\nIt may be that the Al was easier to abrade, and give a greater surface area...say compared w/ a hard stainless steel.\n\nAbrading the surface (then cleaning w/ alcohol)  is standard protocol for applying adhesives to metals and plastics.
580906
Its a buffer and a metal chelating agent. \nIt prevents metallo proteases and nucleases from funcitoning fully as well as stabilizing the pH of the buffer. \n\nRegards
588486
If you mill Aluminum plates to a very fine precision, and then stack the plates together they will become difficult to dislodge from each other.  The reason is not due to suction.  It is due to covalent bonds forming between the two slabs of metal!  Hard to believe isn't it!  I thought so too, even when I got a chance to see it first hand.
452626
The answer seems to be to mix the gold with silver and wrap it in aluminum foil, thus eliminating the possibility of contamination.\n\nSee: http://www.gold.org/jewellery/technology/assay/
864527
the size and texture.
175487
just funky metal\ntry painting the inside with clear nail polish
919374
the common name for that is pewter. it's a cheap material for things like silverware.
219246
You might try different solvents. Such as carb cleaner or lacquer thinner. I'd try on a part you won't see when the telescope is fully assembled. If all else fails use a wet sand paper and re paint. The factory finish is usually a baked on type that lends itself well to cleaners. You might also think of using a green scrubby. Although this might dull the finish. You might then wish to recaot with a gloss or satin clear designed for metal. Good luck in your endeavor.
1019209
Textures, edges, but mostly by size.....
260568
Depending upon whether it is metallic mercury or a mercury compound, different rules apply.\nYou can get some ideas at the site below:
437777
Because it's a reactive form of metal and can easily form compounds. You wouldn't want a material in your body that's reactive otherwise you will be looking for more trouble.