Alternatives for quenching oil - Hydraulic Oils

[Irondragon Forge ClayWorks]

I have tempered small gun springs in molten lead but never tried quenching in it.

I can't control the wind, all I can do is adjust my sail’s.
Semper Paratus

 

[patrick]

23 hours ago, George N. M. said:

Patrick, very interesting.  It strikes me that in testing the hardness of a sample that it could be etched lightly to define the grains and then hardness could be measured by grain and area within a grain, e.g. is a grain harder at its margin than at its center? Or, how much does grain size effect overall hardness.

It would also be interesting to test after tempering.

I recall reading about quenching in molten lead which sounds like more fun than I'd want to have.

"By hammer and hand all arts do stand."

George- You are exactly correct that etching is used to reveal structures before doing that micro hardness test sometimes. A single grain is often too small to measure its hardness and often there are other features located at grain boundaries. For example, in high carbon steels, (those with over about 0.8%) you sometimes find carbide coating the grain. In this case you basically have an M&M structure-Hard on the outside and soft on the inside. Iron carbide is about 70 HRc. Usually carbides are super small, so when we measure hardness with bulk methods like a conventional HRc tester, we are not measuring the hardness of the carbide itself, but the effect that those little carbides have on preventing plastic deformation of the iron next to the carbides. In the case of some very high carbon steels like Wootz (1.5% carbon) or D2 Tool steel (similar or slightly more carbon than wootz) you do see large carbides in addition to the little ones. (I spent several hours today looking at carbides in wootz in preparation for a lecture I am giving next week). If we ignore the high carbon steels and look at the simplest case-pure iron or any other pure metal, we do know that the grain size will affect the strength, completely independent of heat treatment. If I process pure iron such that it ends up with small grains and compare the yield strength to a larger grained specimen, the smaller grain specimen will be stronger. In pure iron, we do not and cannot have martensite, just ferrite or austenite, depending on the temperature. the smaller grained specimen will have a higher strength (not by a whole lot in pure iron, but still a measurable difference) because the grain boundaries act as barriers to plastic deformation in a way that is a little bit similar to the way carbides do in the high carbon example above. The more boundaries there are, the more force is required to make the metal plastically deform. Likewise, in high carbon steels, we can get to fairly high bulk hardness (HRC 40,) without making martensite if we control the size, shape and distribution of the carbides in a softer matrix like pearlite. This technique is used in some things like rail road rails where martensite is too brittle to give a long lasting part.

[George N. M.]

Patrick, again, very interesting.  My interest is because I am an old geologist and what you describe is similar to petrographic analysis of rocks and their constituent minerals.  But it has been a very long time since I looked down a petrographic microscope.

G

[JHCC]

Patrick, thank you once again for both the additional perspective and the clarity with which you present it. 

[BillyBones]

12 hours ago, George N. M. said:

I am an old geologist

George, recently my granddaughter has started collecting rocks. I found a rock that looks like it has pyrite, hemotite, and quartz deposit all on 1 small rock about 2" or so. I say looked like because that is what it seemed to my untrained eye. 

My apologies for thread drift, now back to our regularly scheduled discussion.

[patrick]

George- the earliest folks to look at metals under a microscope (Harold Sorby in July 1863) started by initially looking at rock and minerals, the metorites and finally metals. You might recognize that when I talk about the structures in steel I use terms like "pearlite" "ferrite" "austenite" etc. Those "ite" endings were chosen by the early metallurgists because the structures they were seeing did in fact resemble those of rocks and minerals and the "ite" nomeclature was already well established in that part of the scientific community so they just adopted it for metals. Several of the structure names we use in metallurgy "Martensite", "Austenite" and some others are named after specific people, just as is done in other branches of science.

[Frosty]

There are a number of different pyrites or metal sulfide crystals. Iron pyrite almost everybody knows but the one other that comes to mind right now is Chalcopyrite a copper sulfide crystal.  The cubic structure is sort of natural for metal sulfides and some are pretty heavy subjects like Galena. 

A question Patrick, is any metallic sulfide a pyrite?

Dad was a long term rock hound and it's funny what stuck in my mind and what didn't. 

Frosty The Lucky.

 

[patrick]

Frosty-I don't actually know the answer to your question about the pyrites. That's getting more in the field of mineralogy and geology that metallurgy. That would have been an excellent question for Thomas, who most likely would have know the answer to that one off the top of his head.

[George N. M.]

Most pyrite group minerals are sulfides but not all, e.g. Sperryite (PtAs2) or Geversite (PtSb2).  "Pyrite", in classical times, refered to anything that could strike sparks, hence chalcopyrite which is not a pyrite group mineral in the modern sense but can strike sparks.  Iron pyrite was used in wheel lock guns to produce sparks.

The pyrite group is defined by crystal structure rather than chemical composition.

"By hammer and hand all arts do stand."

[Frosty]

Fair enough Patrick, the etymology(s), there are two involved with pyrites. Pire is a root term for fire. as in pyrophile or pyrophobic. "ite" is a suffix that in this context would be produces or makes. Making "pyrite" loosely, spark or fire maker. 

Uh crystal structure eh? does that make rock candy a pyrite? 

Thanks George, I love this stuff, both the minerology and the etymology, it's a win win.

Frosty The Lucky.

[JHCC]

32 minutes ago, Frosty said:

Pire is a root term for fire. as in pyrophile or pyrophobic

"Pyro-" comes from the ancient Greek πυρο-, which is the combining form of πῦρ fire. Compare with the classical Latin pyra for a pile of wood for cremating a body, from which we get "funeral pyre".

[Frosty]

I misspelled Pyre and didn't read the entire etymology. I know folks who are much better at it than I am so I get to learn more without the skull sweat.  I don't have the links I need to do a proper search, even spending 20 minutes online I kept getting origins from old French, Latin, Greek and long confusing text. If I had more room near my comp I'd drag out my good dictionary, it's so much easier to find definitions, etymology and get lost in its thousand+ pages than filter the guff online.

Thanks John.

Frosty The Lucky.

[JHCC]

One of the nice things about working for the college is a free subscription to the OED.

[George N. M.]

Being kind of a word geek I like having a copy of the Oxford English Dictionary available.  I have the 2 volume version which has reduced versions of the originaal pages at 4 per page and a magnifying glass in a drawer at the top of the slip case.  Not the easiest for use or borwsing but it works.  I got it back in the '80s when I traded a buffalo skull and a couple of antelope hides for it.

GNM

[Frosty]

I'm envious, believe me. I frequently have to search out articles you post on non university sites or pay to subscribe.(not) It's the one thing I really miss from college,  the library.  Our local public library is only OK. <sigh>

Frosty The Lucky.

 

Dang edit time out! I bought an Oxford compact around 1990, it was the latest revision, some 1,000+ "compact" pages @ 4 pages per page and a half sphere magnifier if you want to read the gray blurs. I love that tome. It was well worth the $400+ I paid for it in the day I could afford to buy hard copy books. 

Frosty The Lucky.

[JHCC]

One of these days, I'll post an image of my unabridged copy of Liddell & Scott's Greek-English Lexicon. This comes in two versions: the 816 page abridged version (known as "the little Liddell") and the 1705 paged unabridged (known as "the great Scott"). 

[Irondragon Forge ClayWorks]

I have a copy of Websters New International Dictionary 2620 pages circa 1923 that belonged to my grandparents. Amazing what it contains, I drag it out once in a while to research something Google has no clue about. Weighs about 20 pounds.

I can't control the wind, all I can do is adjust my sail’s.
Semper Paratus

 

[Frosty]

Oooh, beats my trusty old dictionary all hollow! Now I'm suffering dictionary envy, what a way to start the day. <sigh>

So Randy, how long does it take you to look up a word? I usually spend an hour or so looking at other words and definitions. Sometimes I forget why I opened it. 

Ever consider making it it's own podium? perhaps with a fold out writing desk to make taking notes easier and mounted light.  I have a green glass shaded "banker's" table lamp but it looks cooler than it works. Bright green light glares for me and it doesn't look nearly as cool with an aluminum foil shade. 

Frosty The Lucky.

[patrick]

I really love how this thread had changed subjects several time. Kind of amazing how we went from low cost quenching to microstructures and now to word origins.

[Frosty]

One of the really cool things about these branching conversations is it illustrates the parallels in apparently different subjects, you NEVER know where the best answer is hiding so the broader the search the better. 

Frosty The Lucky.

[BillyBones]

8 hours ago, patrick said:

I really love how this thread had changed subjects several time.

Shhhhhh. Dont mention that, else you will summon the puns. 

[Irondragon Forge ClayWorks]

13 hours ago, Frosty said:

how long does it take you to look up a word?

Sometimes I get lost just looking at all the color plates, the first several pages have all the flags of every country at the time and nautical flags. It's really an amazing book.

I can't control the wind, all I can do is adjust my sail’s.
Semper Paratus

 

[Frosty]

I'm going to be keeping my eyes open for a copy I can afford. I tend to really get lost in a real encyclopedia unlike online versions.  I'll have to ask my little Sister if she still has our Grandmother's Nat. Geographics, her husband gave her a lifetime membership in the 1920s. The older issues were in plain brown covers with minimal printing. She put the ones with photos from Africa and Polynesia away so as not to titillate us youngsters. I read it for the articles.  

Nat Geo now days is mostly ads and for things that'd REALLY shock Grandmother. The price is crazy too, I haven't bought one in I don't know how long I can't bring myself to pay to sort through advertising in an often vain search for something worth reading or looking at. 

Frosty The Lucky.

[BeaverNZ]

Thanks guys I enjoyed the multiple subjects, Came for the quench and stayed for the ramble

[Frosty]

Glad to know we haven't quenched your interest. 

Frosty The Lucky.