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Daniel Cauble

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Everything posted by Daniel Cauble

  1. Ran into some frustration because I felt like I was not seeing enough cementite spheroidizing. I figured I would see more for 1.3-1.4%. I nearly gave up on this bar. Them I forged it some more and gave it literally one last etch before chucking it to the side.
  2. It's probably cementite bands. Which is weird because they usually dont start showing up until forging.
  3. Ok, some updates here. I recently built a new, more durable melting furnace able to withstand 3300F using 94% alumina castable.This new furnace I am using a 1.5" blown propane burner I made for it. The first puck made in the furnace didnt turn out the way I had hoped, so I remelted it again with some more, higher carbon material (my oroshigane). This bumped it up to the 1.3-1.4% C range. I have been making 1.6-2.5% C crucible steel in the past, so this lower carbon content was a little new to me. I also purchased an electric kiln to do an initial roast of the puck. Now I have roasted the puck for 22 hours and am ready to forge this evening. What is most peculiar is without even forging, there are latitudal lines already bunched up it appears seperate from the grain boundary cementite. These last photos are 40x10 mag, dirty belt finish, longer than normal etch in 3% nital.
  4. He mentioned the test end was 5x5 microns with a 1g charge. The left side was a pearlite and ferrite strike with the indention being 15% larger and the centered hits are smaller, being cementite or iron carbide.
  5. It was really bizarre to see and try to decipher. Skip messaged me and said ledeburite, and my hunt for knowledge took off. I delved into my microscopy book and many items online. Found a lot of good information, and even stumbled across a bit of research that connected me with an archaeologist in Europe who happened to have already been following my work on IG, lol. Thanks Jerrod, I meant to make that clear.
  6. You are welcome Jerrod. I knew I was pushing into crazy territory, but didnt fully understand cast characteristics until most recently, and what to look for in my product. As stated earlier in this or my crucible thread, I had various samples of my crucible steel and some hearth steel for a researcher to look at. On of the samples was a 4fold piece of hearth steel. He had mentioned then that I had a clean band of heavy cementite, or iron carbide in the piece. At the time it was a mystery, but now things are getting so clear. This is why I love metallurgy and steel creation. Theres so much I learn the further I go in my journey that I am able to critically inspect previous work and findings a refine my understanding. Anyway, the piece was cool and he did take a micrograph, albeit not as bright as mine are. He also used a Vickers hardness test that the microscope was outfitted with to determine between ferrite and cementite structures. Inside that dark band it was showing all of or most of the white to be cementite at the grain boundaries.
  7. I've hit above 4%, lol. Some of that ledeburite pics show carbon in the 3.8-4% range. I've also managed to make some gray cast with precipitated graphite. However, it doesnt play nice so its avoided.
  8. And some crazy widmenstatten structures that are probably widmenstatten ferrite, but based on my sparks on some of it, I swear its widmenstatten cementite.
  9. I've been talking with several archaeologists and even Skip William's (which reminds me that I need to get back in touch with him) about these structures. At any rate, I've gotten better at polishing for pics. Heres some more of steel under 2% C but right at it. Super nice stuff. This material is going into my nihonto projects and kitchen knives. What you see is saturated pearlite with grain boundary cementite. Once the steel is eutectoid, perlite can no longer store cementite.
  10. It's an obsession I've fine tuned for over 6 years now. I've started micrographing my steel from the raw hearth steel. My results compliment findings in historically produced steels found by archaeologists which is neat. I am currently poised to be assisting in creating a large database of structures for other researchers to use. Lately I have pushed my furnace to cross the 2% C threshold and making larger quantities of white cast to be mixed and blended into my steel. Once carbon starts to cross 2%, ledeburite starts to form and the material starts to become a ceramic.
  11. 400x + camera optical zoom. Nital 3.6% (my exact concentration), 12 second etch. Getting better!!
  12. That would be great. As much info as I can get. I currently have the book "Optical Microscopy of Carbon Steels" by L.E. Samuels, for reference. I will also try a shorter etch this next time to see if it helps.
  13. Thank you Jerrod. I am not classically trained in microscopy so it's a learning curve. Looking at yours and looking at mine, I would say mine looks almost over etched. Idk. My left eyepiece has a faint scale bar across the middle but I never use it to take pictures because it has a crack in it. I also remembered I have .25 micron diamond paste.
  14. WOW! 10%?? Does this enhance grain boundaries? I cannot get them to show in this folded orishigane for me. My Nital is more like 3.5%. This time I lightly knocked off the oxides with 12k grit paper, etched for 25 seconds, knocked off oxides, reached for 25, etc for about 4 goes. Enhances the sharpness a little bit, but no hope of etching deeper into the boundaries. Sigh 400x
  15. I just made my own Nital with 68% Nitric and Methanol. yikes! Will do.
  16. Some micrographs of the core steel. The core steel is again W2 sandwiched between orishigane. A few show the clean weld of the two disimilar metals. I need to obtain a few more etchants to show grain boundaries.
  17. Picral, and then another that I dont have a name for that is a mixture of ethenol, picral, nitric and HCL. The picral will help bring out cementite and leave ferrite alone. The other mixture should show grain boundaries.
  18. Finally proper etchant this time, with other regeants on the horizon for different structures. I'm taking pics through the eye piece so they arent perfect or particularly crystal clear but you get the idea. 50, 100, 200, 400, 800, 800+optical zoom
  19. Same blades, no change in finish. Just got an inverted metallurgical scope an testing it out. The 800x objective is being funny so not using it yet. Remember, Ferric etch. Still waiting on SEM results of this steel.
  20. I said screw it and started polishing it for kasumi anyway (japanese natural stone polish). Long way to go :0
  21. Nickle doesnt like leave the steel all too much in this style of melt. Are you taking this chunk to forge welding temps to work it into a welded bar?
  22. Have been working on the ability to push carbon into high carbon steels to make them higher carbon steels using higher carbon orishigane and carbon migration principles laid out by Verhoeven. This orishigane was pulled from the furnace and knowing how well I can make ultra high carbon steel from one end of the puck to the other, used the entire mini-bloom of orishigane. Folding was conducted using my own formulation of mud and rice straw ash. From there it was folded 9 times and laid to rest until I was ready to use it. The spark yielded a rather high carbon spark. Much higher than W2, so I set out to sanmai weld W2 with orishigane at mid to high temp welding heats with soak in hopes of pushing carbon into the W2. Then drawn out into a billet to be used as core material. From there I constructed a sanmai with this material and my usual 1018 mild jacket. This time using a lower temp forgeweld to mitigate migration into the mild. Drawn out and a gyuto was made. Hardened using japanese Ht techniques and just got done machine grinding it. On to hand sanding. Unfortunately I dont have time to make this a kasumi style kitchen knife and stone polish it like I really wanted to as this is going to Bladeshow and I dontnhave time. So sandpaper, loose abrassives and etchants it is.
  23. Btw, my original assertion was that the steel was 1.7%. Which is reaaally close to the 1.64% C it tested as. This is vindicating. Also i would love to share the results of the suspected cast pucks but will put that in hold until something is written up.
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