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The crucible furnace has been demolished because I thought it was done ( major mistake )  ...I will make another one. I have 8 pieces of metal to forge , all of which are lower in carbon content than what I used to make in my previous life. I am expecting one ( the last one to be forged ) to hurl me into the past..I may already be there by the time that last ingot comes around.  I am still hoping to find the missing ingot ( failure, full of holes ) to see if it will offer any info.

In the picture below are from left to right, ( in the order in which they were melted )

 

Low P, High P, MedP, Large Med P, Failed FlatMed P, Failed Flat Med P,  Standard Med P, and Standard  Med P.

 

IMG_4176.jpg

Edited by Jan Ysselstein

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It is rough go at the start here ..I am experimenting with some of Al's advice. I may have to go for a decarb layer just to be able to weld a rod to the ingot. I dropped ( bounced ) a hot ingot into my water bucket and took forever to fish it out with the tongs. A few cracks but I will forge as long as I can before discarding the ingot. I need to get a better microscope connected as I am seeing cementite convert to spheroids but I am not sure what percent of the material is doing this ( they are occupying the same area). It will take me a few weeks to get through this batch.I am currently trying to forge MedP smaller ingot.

Edited by Jan Ysselstein

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There are now 4 pieces of steel left to forge. All the ingots seem to have a number of small gas pocket in them...these become cracks during forging. Left the forge and it just kept getting hotter and hotter...my big ingot cracked.when I put it under the hammer....very annoying but I will make some lemonade from that. I am still chipping away at the first ingot ...though badly peppered with holes I should end up with a bar. I will remake my furnace this week end and create a few more ingots without bubbles ( I hope). I am looking at adding a simple controller on my forge...it is hard to stand there all day monitoring the temps. Here are some pics.

The good new is ..I have gotten my forging routine back and if I can stay alert I should get some bars ( imperfect as they may be ). 

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First ingot hammered from the top, about to turn it sideways and draw it out.

 

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One discard for lemonade and one hoping to make it all the way....things are starting to click. I am keeping records of the  microstructure from as cast through the various forging stages.

Edited by Jan Ysselstein

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That ingot on the left will not be making it..I will cut some fragments to see if I can observe the movement of the highly dendritic pattern. Now I am down to 4 ingots, the High P will be forged next. A set of 4 crucibles have been prepared for the next run. I will try to measure some temps next time as I am thinking I am running too hot and my glass is not the right chemistry. I need to conform my forging practice closer to what Al is suggesting ( such an impatient wootz maker) ....I think I am reheating sooner than Al's suggestion because that ingot looks cooler than it is.

Have I learned anything from this disaster and was it worth the effort ?    YES,YES!

Below is a pic of the flat ingot ( cut in half ) now discarded. This is a carbon network which only partly shares location with the dendritic network which can be seen by thermal cycling.

  frame15.jpg

 

Edited by Jan Ysselstein

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The high P ingot is the only ingot with low number of voids...I was able to forge about 1/3 of an ingot to about 3/16". The dendrites are becoming very distorted , this is a picture of one of the few still recognizable . I am quite pleased with the developing pattern. The austenite etched pale color indicating the carbon there was in spheroidal form.  I do not have a camera right now but will post a photo once I am done messing with this piece.frame8.jpg

frame8.jpg

Edited by Jan Ysselstein

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That is about as far as  can go with the sample I have thinned it as far as I can..now I need to move the cementite to spheroids and see how much that will change the pattern..I have not yet manipulated the surface for effect.frame17.jpgframe6.jpg

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This has been interesting- appreciate the updates and the pics :)

Dave

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I have tried to dissolve most of the cementite while trying not to lose to much carbon from the surface. I did not get it all, the hotter areas of the sample seemed to have more cementite missing. Now I am accepting a low level of residual cementite particles and am going to try to move the carbon to the areas having the micro alloys.

The areas in the pictures that are now white should turn dark ( pearlite)

The areas that are now dark will become bright and full of spheroidal cementite ( I hope).

My sample is approaching the thickness of a sheet of paper.

This is very exiting. 

frame5.jpg

frame6.jpg

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Hi Jan

Just spent free moments over the past two days reading this thread, I also do not understand even half of what I would like to, but I find the whole topic so fascinating I wish I could look over your shoulder for the whole process!

Thank you for taking the time to share.

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Thanks guys, looking over my shoulder would be shocking, as the process is quite crude. The above bar was forge welded once ( onto itself) to maintain thickness , the weld is good .

I am dissolving some cementite in a gas forge..so I do keep an eye on the temperature with a thermocouple. In the above case , I soaked the bar for just under an hour at about 950 C..pulling it out every now and then and fluxing to avoid carbon loss. That worked quite well where the surface was clean and not scaled. Next time I will soak to dissolve for two hours in a protective piece of tubing or heat treating foil. Growing spheroidal cementite is a charcoal forge method all done by eye and a Magnet with careful control of the air flow.

Growing the spheroidal particles is a skill I am trying to learn..slow is good..slow is very difficult for a person living in the digital age.  Another skill I am hoping to learn, is to quench to Bainite  and or fine pearlite..... No salt pots.

There are some forging methods available that may eliminate the need for this loop but I have no ingots to forge this week.

The new furnace shell is done and I will melt more iron next week.

Edited by Jan Ysselstein

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I just remembered I do have another bar to take through the pattern developing process, it is this one...

I will weld it by folding once and forge it..and try to get it into a state of Martensite, Bainite , Fine Pearalite or a mix of some of  these. 

post-1617-0-00201000-1429110505_thumb.jpg

Edited by Jan Ysselstein

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Now going back to the sample above. An area of the sample did what I wanted to but some off the surface has not converted. The pictures below show a fine cementite ( spheroidal ) structure and a background etching black. Back to the books to see why. Now it is getting really thin and I will abandon it.

frame1.jpg

frame2.jpg

frame3.jpg

Edited by Jan Ysselstein

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In a day or two, I will forge weld the above bar ( same as shown in these pics) onto itself ...two 4" long pieces...welded and forged into a bar about 12" long. I could just forge out what I have as it is about 3/16" thick.....however I have a blade I would like to be inspired by and it will require me to use the pretty surface of this bar as the welding surfaces ( high risk behavior ) and to have the rough pattern become the exterior surface(s). I think the pics will explain my thinking. The spheroidizing will be done  using the DET ..I will try not to grow large cementite during forging. The last picture ( the blade ) is the one I think is similar to in nature to the two pics above it. The blade picture was provided by Jeff Pringle.

IMG_4285.jpgIMG_4287.jpgIMG_4293.jpgIMG_4290.jpgjeff'spic.jpg

Edited by Jan Ysselstein

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The forge welding did not work on this sample for reasons I am not sure about. Now we will have to find out why...I have welded it in the past and just recently. I really do not have enough material to take this detour right now, however my plans depend on being able to weld this material.

I will play with the remnants ( this is all I have that I am willing to gamble with)  to see if I can get anything worth looking at..I should be able to weld something here if I have enough material.

IMG_3892.jpg

Edited by Jan Ysselstein

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Bummer. I was really rooting for this one too. Watching your progress is both motivating and scary at the same time. I feel your determination and I so want you to succeed. 

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Thanks Josh,

Things are coming together..I will use the above twisted bar to confirm the heat treating sequence. Things are looking good for wootz.

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The twisted bar sections are very thin and I do not think I can take them through the whole heat treating process. I did run into a piece of bar #2 from very early on in this thread..I am posting pictures  of a relatively small area of number 2. These edges were heated the most both during the quench and during the thermal cycling....it looks like the TC is working. Most of #2 still has a lot of large cementite which I will try to displace.frame3.jpgframe5.jpgframe7.jpg

frame2.jpg

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We are up and running again...I have made some charcoal ( Pit Charcoal Thread) and plan to smelt tomorrow ( inside the shop). I am in the process of making an improvised propane fired tempering furnace ( should be able to hold 21"long material )  controlled by a digital controller.  This furnace is 10" in diameter while my forge is 6" in diameter. I bought a point and shoot and will be able to better document the details. The crucibles have been fired and are ready to go....most of the work now will concentrate on duplicating some of the results from ingots 8 through 10 above with less forging trouble.

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