If you add enough pressure to distort metal you cause friction and friction causes heat, the heat is sufficient to "weld" - whatever you are joining.
You tell that to my brother-in-law and nephew (both electricians), and they will have a good laugh..... of course it matters for both AC and DC - it governs the current the cable can carry. I refer you to fuse wire as an example.
[..]
A reference to a "set of dies" does rather tell you of harsh use - eg subject to impacts therefor excessively fine tolerances are not wanted/needed. Further to that the tools are much finer than commercially bought similar items. They are quite sufficient to demonstrate the effect.
There are two ways to bond mokume. Three if you count a melt down as one :)
Difusion bonding, done under pressure and under the mealting temp. of the resulting alloy at the bond surface.
The 'sweating' way, where it is done under much less pressure and idealy right at the melting temp of the alloy made at the juntion of the base metals. If too hot the base metals start to melt and that happens too often to me :( But I have learned better too hot than too cold.
So "unique" that you cannot find a hole in the arguments I put to you, instead you find a need attack me personally not only on this but also "in so many other areas" - your mere assertions amounts to nothing. Remember the last time you resorted to something like this - can I just mention "slide rule" to remind you, hmmm?
"Soluble" is a word that refers to something dissolving into a liquid mixture of (whatever). You cannot have something "dissolve" (also related to "solution") into a solid so it remains solid! Impossible!
SOLUBLE - adjective 1 (of a substance) able to be dissolved, especially in water - OED. DISSOLVE - verb 1 [no obj.] (of a solid) become incorporated into a liquid so as to form a solution - OED. SOLUTION - noun 2 a liquid mixture in which the minor component (the solute) is uniformly distributed within the major component (the solvent). [mass noun] the process or state of being dissolved in a solvent. - OED.
The question then was whether 43/7 equalled 18/3. I said it didn't. You insisted it did. I think I abandoned that argument at the point when you effectively resorted to arguing that 'approximately' is identical to 'exactly'.
Apart from that, those forging blanks were NEVER hot enough to melt. It was NOT NECESSARY that they be melted for them to be reformed. One of the reasons for forging is to presever the original grain flow of the lank and that would be lost if the blank was melted.
"Hydrogen embrittlement is caused by the presence of hydrogen atoms within the crystal lattice structure of a metal or alloy. In the galvanising process, hydrogen may be absorbed in the steel during the pickling process through contact with the hydrogen ions present in the hydrochloric acid."
The definition you quoted is correct for the world of cups of tea etc but has to be expanded to take into account the wider range of phenomena experienced in the real world.
I can no longer recall the number, and care even less - FACT is that they are close enough to being equal. So in ancient times if they used shit houses as one set of measurements, and yard arms for the other, they are close enough considering no fractions were used - a measurement for which an APPROXIMATE conversions was given - a measurement for which that level of accuracy is more than adequate.
You came unstuck on that one and still are all at sea with it - as your recent argument about a nautical mile and "great circle" circumference measure, which is ANY circle around ANY part of the globe, when the specific circumference given was at the equator - nowhere else. Something that varied sometimes by a few meters - like WOW!!
When ONLY approximates were given then only an approximate can be VALID and can NEVER mean your petty hair splitting "accurate" claimed to be achieved FROM an "approximate" - it can't. Simple as that. You are resorting to the same sort of nonsense game again!!
Prove it!
Prove it! Remember you are talking about a fraction of a second in time as well.
(I have no idea what relevance "long, limp, and straight" (lank) has to anything here so I'll ignore the term.)
Not true for the particular example given - other similar items are cast and machined in the traditional manner. Again you only make totally unsubstantiated assertions and do not speak about the reason WHY at all! You know, that thing that makes it work and proves your claims. Haven't you found it on the net yet?
So let is look at this "grain flow" claim:
This is advertis "Forging refines the grain structure and improves physical properties of the metal. With proper design, the grain flow can be oriented in the direction of principal stresses encountered in actual use. Grain flow is the direction of the pattern that the crystals take during plastic deformation."
So a lot of gobbledegook in reality if compared to your "expert" claim of "preserves the original grain flow" and "cold". Which is a load of nonsense for the example I provided - it isn't important. What IS important is unit speed of production and therefor unit cost of the production. So slam two dies together and form a crown wheel for a Mini in a fraction of a second at tremendous pressures like up to some 50,000 tons and tell me no part of it did melt at any stage! Oh and you call this "cold forging", when the more correct term is "Open-die forging" or "Closed-die forging" or even "Two stage closed-die forging". There is nothing "cold" about it.
Oh and to finish off with the golf club:
"Ageing the head at elevated temperature optimizes strength and softness." Oh well...... so much for the "cold"....
It isn't mine - it is merely the world authority on the English language you are saying is "wrong".
See, no mention at all of "soluble, solution or dissolve" even though a solution IS involved. This is because the are not relevant! Mind you I really would like to see "pickled steel" I wonder is it anything like pickled onions.... or gurkins..... still it has nothing to do with the actual subject - copper and annealing which is NOT "galavanising steel" involving "hydrochloric acid"!
The definitions *I* quoted are the accurate for the English language and they really ARE the "real world" you know. There does exits perfectly good words for other processed eg - as above "absorbed" - you do NOT need to abuse and misuse the language.
"Noun 1. solid solution - a homogeneous solid that can exist over a range of component chemicals; a constituent of alloys that is formed when atoms of an element are incorporated into the crystals of a metal"
And:
"solution - a homogeneous mixture of two or more substances; frequently (but not necessarily) a liquid solution; "he used a solution of peroxide and water"".
Seen it - it doesn't advance your claims at all cnosidering the "grain flow" is not a consideration.
Nothing there - doesn't discuss the process I mentioned.
So why is it that you are totally unable to explain it?
A parrot on a cage can do just as good as that - therefor it is arguable the parrot's knowledge is comparable to yours :-)
You cannot know what they have in mind for "elevated" it is a relative term and all you can relate it to is the melting point. In that case it is far more likely the "elevated" is far greater then 700C!!
Learn what? You have provided nothing to learn from! On the other hand, you are in the process of learning youself. Here is another lesson for you:
"A material exists as a solid when it is below its freezing point." and "Keep in mind that a material's freezing point is the same as its melting point." - Steve Gagnon, Science Education Specialist!
Please don't confuse "solid" with "solution" again.
CONTEXT - you missed the CONTEXT that governed the terminology and therefor its meaning.
Eric's reply was:
"At high temperatures oxygen is soluble in copper" to the question "How does the gases get in that causes the bubbles?" in relation to annealing.
Therefor it is NOT possible Eric was referring to the chemistry of a solid mixture containing a minor component uniformly distributed within the crystal lattice of the major component because:
(A) it doesn't "dissolve" into the copper because of annealing the reasons being (i) It requires the movement of the crystal structure to create spaces to "dissolve" into
(B) IF spaces exist there already is something in these spaces as a vacuum cannot exist. (i) It means the material is porous enough to use as a filter. (ii) The copper is not pure. (iii) If the substance in (i) is oxygen, then it would revert to a copper oxide in no time and couldn't exist as pure.
(C) Your term fails completely as in the annealing process it is NOT possible to get anything "uniformly distributed within the crystal lattice" of a piece of copper, as is required by the term you attempt to use.
(D) The (whatever) that is uniformly distributed within the crystal lattice has to be there from the moment of the crystal formation. (i) Then it cannot be the answer given by Eric. (ii) There is no proof there IS any space to contain anything in pure copper (remember it includes MODERN melted pure copper) in the aforesaid form.
All this is something that really needs no thinking about - it is self evident and obvious from the moment of seeing the term. Your attempt was another of those "Good morning - Axe handle" type cases.
Incorrect. Consult a good welding text such as "Modern Welding" by Althouse and Turnquist (the most widely used, and most authoritative, welding textbook).
It is true that fusion welding produces a HAZ (Heat Affected Zone) around the actual weld joint. This can significantly alter the properties of *some* materials, namely medium and high carbon steels, some alloy steels, and some aluminum alloys. But *part of the welding process* in those cases is post-weld heat treatment to restore those properties to their original pre- weld state. In other words, you haven't completed the welding process for those materials until you've done the post heat treatment.
For materials such as mild steel, the most commonly welded material, there is no such concern. The HAZ doesn't affect the material properties. That's because mild steel has too little carbon in the solid solution to produce the phase changes that could alter its crystaline structure. A *competent* welder will also choose an appropriate alloy filler material so that the fusion zone won't have different properties from the parents either.
It is well to note too that different welding techniques produce differing size HAZ. TIG welding produces less than arc, MIG produces less than either, and exotic techniques such as laser welding produce practically none at all.
Now you are postulating *cold welding* for the gage blocks, and that produces *no HAZ at all*. So the material properties surrounding the weld joint would not be altered *at all*. Of course cold welding isn't what's actually happening when you wring gage blocks together, but if it were, you'd still be wrong.
Metallurgy for Engineer's - Rollaston Mechanical Metallurgy - Dieter The Practical Use of Fracture Mechanics - Broek Pressure Component Construction - Harvey Creep of Engineering Materials - Pomeroy How Components Fail - Wulpi Practical Stress Analysis in Engineering Design - Blake Mechanical Engineering Design - Shigley A Procedure Handbook of Arc Welding - Lincoln Electric
... and none of them agree with you.
An analogous process is the natural welding by spontaneous adhesion of frozen mercury when constructing molds for precision casting.
I've already answered this but you deserve a better response than a mere battle of authorities.
OK, you have partly acknowledged my main point, that there is a discontinuity around the weld. In this case it is the 'heat affected zone'(HAZ). Now, not all HAZs need post-weld heat treatment, but HAZs still exist.
The metallurgy of the HAZ is visibly affected as can be seen in the micrographs in
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variation of the mechanical properties of the material in the immediate vicinity of the weld can be seen in diagrams at the same site.
More information is available at the site of The Welding Institute at
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It is a common view that the resulting weld will be strong if one uses a weld material that is stronger than the parent material. However fusion welding is a casting process and entails a puddle of molten material cooling down and solidifying. The resulting shrinkage requires local yielding of both the parent and weld material. If the weld material is too strong it will not yield and all the shrinkage has to be pulled out of the parent plate. Even if this does not cause cracking it leaves high residual stresses.
Someone will now say that you can relieve the stresses by heat treatment. That is perfectly correct but this further modifies the metallurgy of the weld zone and some of this may be adverse. Grain growth and embrittlement is a particular problem.
The reason why any discontinuity in properties at a weld results in a local weakness is that the mechanisms of failure are complex. Even ignoring any geometrical disturbances caused by the original welding, deformation will occur in the metal when stresses are applied.Tension applied to a plate will cause it to become slightly thinner and narrower. At low stresses the deforemation is elastic and the plate will return to its original shape if the load is removed. If the applied load becomes sufficiently high yielding (i.e. plastic ceformation) will occur in the material. If there are local variations in the material properties (e.g. at a weld) some parts will yield before others. This will result in a local redistribution of the stresses and the stronger parts of the material will end up carrying more load than they would if they had been surrounded by a material with a higher yield stress.
Now it gets really complicated. The local material is subject to a mixture of tensile and shear stresses. The interaction of these gives rise to 'principal stresses'. there is a principal tensile stress and a principal shear stress which acts at right angles to the principal shear stress. With some meterials it is the principal tensile stress which causes the failure and with others it is the principal shear stress which causes the failure.
The metallurgical discontinuities associated with a weld give rise to local disturbances in the stress pattern. These give rise to local variations in the principal stresses. Some will be higher than in the undisturbed parent plate. Others will be lower. Some parts of the weld zone will be less likely to fail than the parent plate but there will always be parts more likely to fail than the parent plate. It is at these latter locations that failure will commence.
That's why I say a weld is never as strong as the parent material.
Unless the weld is perfect, it still leaves an interface detectable by microscopy.
Its not just the properties 'around' but the properties 'at' which matter.
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