In Search of Hamon, Experiments at the Forge #1

[Jan Ysselstein]

I have always been fascinated with the blades I have seen showing a beautiful differential quench line. Looking at the boneyard, I pulled some samples which have been saved to experiment with. I will include the bloom/cast iron melting experiment I started here,

http://www.bladesmithsforum.com/index.php?showtopic=30923&p=310015

 

As a totally unbiased experimenter I must admit I hope the homemade steel rises way above all others as that is where a lot of energy has been placed.

 

Here is a list we can have a look at, most of these steel may not be suited to participate , we will find out soon. Remember , this is mostly junk.

bloomery/cast iron crucible steel

same

soft bloomery iron, carbon to be added later

folded file pieces

melted file blade blanks

forged medium carbon bloomery iron, to be mixed with high carbon bloom and welded

fragment from an old gang saw

clean Japanese blade steel, white #1

sled runner from an old ox drawn logging sled

World War 2 era large drill rod machined and 1 1/2" dia

I have a few more I am unable to pull right now, old leaf springs and more runners from sleds.

 

My next step is to finish melting some bloomery materials to about a 1% carbon level and practice some forge welding in a gas forge ( all welding will be done with a gas forge ). Design a simple blade shape, to be formed from each material. A basic 1" wide kitchen knife (looking a little like the melted file steel blanks). Set up a standard normalizing/quenching/tempering method for each steel.

Jan

 

I tried to edit the title of this post and place a comma after hamon, but could not do it...would one of the administrators doi it please

 

It shoulld read in search of hamon, experiments at the forge #1

Edited August 17, 2015 by Jan Ysselstein

[Jan Ysselstein]

Administrator..Thank you for the edit.

 

The melting of the crucible bloomery mix has gone roughly like this...1 hr +, to get the crucible to temperature plus 1/2 hr to 40 minutes to stopping. I will run at high temperature for a full hour from here on.

 

Jan

[Jan Ysselstein]

The last ingot was held at temp for 1 hrs. and still had a little gas ( maybe the time should be 90 min. , or I need to get rid of that cold spot under the center of the crucible )..I should be able to get a couple of chunks of solid material large enough to forge a blade or two. These will be good for comparison to file steel. This last ingot, #3w was made from old wootz stock mixed with bloomery iron 50/50.

I have included a photo of a shop visitor ( I thought I was sole smithing but not so ).

There are some other forms of iron on the horizon which will be tested for the hamon appearance..since cast iron is now our bloomery product, we will begin testing some high carbon iron made directly from cast iron ( an indirect process ). The making of cast iron is an indirect process as well so that steel will be an indirect steel squared.

 

Next steps are to get some solid material from ingot 3w and to flatten/fold all other ingot material into bars..test for carbon by sparking.

Shop visitor

Very hot crucible just pulled and placed into a SS cylinder

Still hot a little later

All ingots , # 3w is the latest..we will try for an all solid ingot later

 

Jan

 

Something happened to my pics an I am not sure how to fix it.

Edited August 20, 2015 by Jan Ysselstein

[Jan Ysselstein]

Here are sompics of ingot #3 as a beginning bar. We went from the forge to the hammer some shut folds but I think we will get some kind of a blank. I should have welded it onto a rod. This is fully melted steel, the interdendritic regions are diffusing away ( slowly, as I am forging at a low temperature, you might wonder why ) The bar stocks have all been flattened and normalized, for a quick quench to see how they will handle a water quench.

A couple of surprises...1) white#1 is a really strong steel 2) the big saw blade steel looks very good, very strong spark.

It seems based on the spark test that bar#3w has the lowest carbon content..all sparks of all steels look very similar.

this is a dendritic steel after all, 2mm field

7mm field

 

Jan

Edited August 20, 2015 by Jan Ysselstein

[Jan Ysselstein]

I should be able to quench my now "clayed " samples of File steel, Melted file steel, Saw blade steel and White paper #1 steel....I will do them in water at about 100 Def F/ 38 C . If the clay adheres to the blades we should get a hamon. I have had some problems with adhesion, and will take the clayed steel through another normalizing cycle in a charcoal fire before quenching.

So we are quenching .8 C - 1.2 C steels ( based on Guess work) normalized 2x into water at 38 C ( at bout 800 Deg C), quick fire pass to pre-temper the martensite a bit and we will be looking for a quench line, little cracks, and not pieces of steel at the bottom of the quench tank ( I hope).

 

Here is what the gang saw blade looks like, a heavy blade of constant thickness bolted in to a strong wooden frame.

Edited August 21, 2015 by Jan Ysselstein

[Jan Ysselstein]

This is going to be fun....maybe. I quenched two pieces last night, file steel from a ground down file and a piece of that large saw blade

 

The clay blew right off the file steel into 40 Deg C water....the file was quick tempered ( not normalized ) and reheated by edge heating only , then quenched without clay.

The saw steel clay stayed on but the steel played a rhythmic sequence of tics ( maybe as many as four) after a second or two under water ( we may have an oil hardening steel here ) ...so I will try it again.

 

The file shows a clear quench line and will be sanded a bit more before taking a photo of the blade...this method ( no clay, partial heating) looks to be quite adequate.I regret not having brought the spine back to pearlite before quenching it a second time. That pearlite spine would have given me a better final contrast.

 

Today I will try to look at the saw blade and create a plan for the next try. I still have melted file steel and white#1 to quench.

Jan

[Jan Ysselstein]

]So , here are some pictures of my disaster. Both test have delivered some good news. By the way 40 Deg. C is quite warm to the touch.

 

The file....this is just a Nicholson file with the teeth ground away and forged a little to a shape ( no melting involved ) . I do not know a lot about what it is I am seeing, however the nature of what appears to be a hamon is just what I like..I want the transition of contrasts within the hamon area to be subtle. In other words , I do not want to be able to tell exactly where the clay was applied by looking at a blade.....that will not be a problem if no clay ends up getting applied as in this example.

 

the thin dark line above the hamon is probably pearlite the area above that , who knows

this out of focus picture is included as it suggests a bottom to the clouds

 

 

 

The saw blade fragment..this test has to be repeated with a bit more thought and planning ( before going to oil ) but the good news is it has a tremendous banding going on, so though the hamon if any eludes me, the hada should be great.

I am not put off by the cracks during a learning curve, note the potential Hada

 

I am sometimes put off by posts assuming all readers know the meaning of some of the Japanese iron working terms. As we get into more of these I will stop and write the definitions. Hamon is fairly well known, but Hada should be defined, as I have seen it used incorrectly at times.

 

Here is a microscope pic of the saw blade steel , these variations in composition seen are due to dendritic growth, micro and macro segregation of material in the melt.

Edited August 22, 2015 by Jan Ysselstein

[Tim Mitchell]

Hey Jan, good work with your experiments! You got some nice sized gas bubbles in the ingot there, perhaps if you added some calcium or a tiny bit of Aluminium to the charge it may help with removing the excess oxygen from the ingot so it will be bubble free. Sometimes rust can cause bubbles in a melt. Also new crucibles have the ability to do that as well. Looks like you are doing some very interesting stuff there.

Well done.

Tim.

[Jan Ysselstein]

Tim,

Thank you.

This experiment and the wootz thread experiment will go well into next year as I have a lot of unrelated stuff on my plate right now.

The gas may not be as big a problem as it seems. I have to make sure I am at, all liquid ( the dendritic structure tells us that, an etch of the cut surface would confirm that as well) and find out where the shrinkage cavity wants to happen. I have an air preheater in mind but will wait until the rainy season to test it.

 

So far, all I have is a ground down file haphazardly quenched in H2O at 40 C, showing a very good hamon potential ( not fully tempered as of now )

and a piece of cracked saw steel, 5 cracks, showing a tremendous amount of banding..this may not be a water quenching steel.

I have tested the white#1 and have to repeat it...I do not have enough of that material to go on for very long.

 

In the end we should find out if a shallow hardening steel with very fine banding ( as might be found in a quickly cooled little ingot, forged into a blade ) has an interesting character, when compared to welded steel of roughly similar composition and to welded bloomery iron.

 

One thing I have learned is that both white#1 and file steel can be quenched at 40 C in water and harden. This is more about my comfort level, as I have seen cracking in the past.

 

Regarding the deoxidizers..I hope not to use them....what I really need to do is spend more energy making clean bloomery iron, though the last crucible #3w had a black/greenish glass layer .

I see the glass as a broom sweeping up all the oxides from the bits and pieces in the melt.

 

Jan

[Jan Ysselstein]

Trying to get back into this.

 

The bar in the attached photo is 1/2 of an ingot made of 50% old wootz and 50% soft bloomery iron ( ingot 3w ), It has been ground to remove laps and is ready for forging again.

I am going to streamline this topic as too much has been bitten off.

Folded bloomery steel and folded cast steel.

I will be sticking with slightly modified file steel ( melted into 1000 gram ingots )

Homemade steel of varying compositions , all shallow hardening clean steels

A few more trials with that expensive white #1 ( expensive for now and when I start making it , it will get really expensive )

The large saw blade deserves some attention , not because of hamon per se , but it's structure is worth investigating.

 

Hopefully the cracking of blades will stop and things should be looking better.

I will include my favorite Bladesmith Forum Photo if I can find it, this is Simon's photo and I should soon be able to match it

my favorite Bladesmith Forum Photo

 

The video of the numerical simulation of a Japanese sword quench seem to be off the internet does anyone know why that is?

Edited December 1, 2015 by Jan Ysselstein

[Jan Ysselstein]

I am about to pick this topic up again. Fresh bloom material only will be used..most of it has too low a carbon content to be called Tamahagane but that can be fixed. A 100 lbs. bucket of bloom material is waiting to be processed into a high carbon steel . The routes to this end are numerous and many are being used on this forum..some are a little exotic but can be done never the less. If this 100 lbs of bloom were clean ( no slag attached ) it would only take 1 liter of carbon powder to raise the carbon content from (guess) .2% Carbon to 1% Carbon.

 

The idea of raising the carbon level of low carbon bloomery iron, came from a member here ( a formerly semi-professional blade smith, currently a sole proprietor ) . The question was posted regarding why carbon is always being reduced from iron to make steel and why is it not more common to go in the other direction. That question had a hook for me and I have given it a lot of thought. One may create a list of how many ways that can be done by a blade maker...there are quite a few ( some are related and overlap each other). We can do a couple of them here. I will edit some pics of the bucket into this post when I take them.

 

Jan

[Jan Ysselstein]

We are going to duplicate the sample made in post #1 of this thread....cast iron and a lower carbon bloom....a carbon content of just over 1% will be attempted. I have been away from all this stuff for a while and have to get some bugs out before feeling comfortable in that space. A cold spot in my forge is driving me nuts, I have diverted the gas/air mix flow away from the work and do not seem to be getting that hot. Working large blooms with my underpowered press is difficult...I am going back to first sized bloom fragments for refining. Finding high carbon iron by discovering your band saw will not cut the material is bad news,,,I have been doing some severe quenching to get the fluxed slag to jump off the flattened bloom pieces, but that will harden even a fairly low carbon piece of iron.

 

So we are upping the carbon content of bloom or lowering the carbon content of cast iron to get into the carbon content range of Tamahagane. Later we will do it with straight carbon as we did here in sample #5 of another thread ( http://www.bladesmithsforum.com/index.php?showtopic=30923&p=298844) (poist #18) , this sample is still alive and I will final forge it and shape it prior to quenching..it will now become part of this thread.

 

The obvious question to be answered here is, the gain/loss obtained by` forging and welding the ingots or just working them into a blade form.

 

So ,the next few samples will be made from cast iron and bloomery iron ( these are both made in the same furnace using the same ore and pit charcoal ).

 

low carbon bloom material, the bloom at the top is the last bloom in "Pit Charcoal"

samples of smashed unrefined bloom and cast iron, for Tamahagane preparation in crucibles.

 

Here are some pictures of the unrefined bloomery iron shown in the dish above , this sample is very clean ( that is not always the case) and was forged at a very high temperature.

The field is 7mm

The field is 7mm

Edited July 19, 2016 by Jan Ysselstein

[Jan Ysselstein]

Did my first melt in a while...cast iron and soft iron, both smelted in one of the furnaces shown in "Pit Charcoal". The crucible was pulled after 1 hr at heat and is cooling rapidly in a SS beaker. Aside from forgetting a little glass as an addition, the melt seemed to go pretty well. The furnace was made by just turning my welding forge sideways and standing it up rather than leaving it in the normal horizontal position.

 

The material I am after is a Tamahagane, though by changing a few words and cooling a bit slower we could be talking about Wootz or some of the other crucible steels seen here in these posts. If the material looks good we will do a few more ( I have another filled crucible , waiting to be fired this evening ). The total weight of these two ingots should be 1000 grams each. I have made some larger crucibles intended for a central Asian wootz trial...but I may use these here, ( that will be my first try at using these large crucibles ) ...then we should be able to go up to about 4-5 kilograms of metal...maybe I better get some shoes instead of these thongs.

 

Here are some pics of todays melt..I hope the ingot is photogenic...if not, we will call this a welding and folding part of the experiment.

 

Jan

Edited July 21, 2016 by Jan Ysselstein

[Jan Ysselstein]

The first ingot was removed from the crucible and seems pretty solid...because I forgot the glass, I have some trapped gas under a solidified top ( not too much). The second ingot is cooling, it did have some glass added,I hope to point some pics tomorrow. The second ingot was at temperature for 1 hour as well.

 

The spark test indicated a very high carbon iron ( the expected carbon content is at about 1.6% carbon

 

The total propane consumption for the two ingots is 15 lbs. or 7.5 lbs each or 1.8 gallons per melt

 

The second ingot just after pulling

First ingot

First ingot

inside surface of first ingot crucible top, showing prils in an oxidizing environment ( glass will fix that).

Edited July 21, 2016 by Jan Ysselstein

[Jan Ysselstein]

The second ingot looks pretty good..I found some razor thin wall thickness in my crucible..lucky for me that area was supported on a pillow. I will cut both ingots to determine porosity.

 

 

[Jan Ysselstein]

The first of the two ingots is porous , the second is completely solid. The third ingot is bigger, maybe 1600 grams and it was just pulled. The propane use was 12 lbs due to a much hotter run. I will pull the third ingot tonight..a fourth ingot is staged ready to go...after that we are looking at welding and quenching.

 

A question to come up is, how the various metal samples will be treated prior to quenching and during quenching .....to make sure there is no bias in the tests.

I will post some pics of the cut ingots soon.

 

Jan

Edited July 22, 2016 by Jan Ysselstein

[Jan Ysselstein]

Some of you may see these ingots as more of a wootz project than a tamahagane project....after looking at the microstructure of the second ingot you may correct. In any case we will go ahead and forge everything into 3/16" plates...quench and break it all up into bits ( we will lose a little carbon on the way, by design as we are a little high in carbon)..let's hope the welding goes well. The third of this series of ingots looks good up to the top 1/4..then it gets a little porous. I will try to eliminate the porosity on the last ingot ( the fourth in this series) by addressing both causes.

Here are some pics

the second ingot has micro cracks due to heat while cutting ( into the "to be welded pile"

the third ingot , mostly solid, it will be forged and a non welded blade will be made

top of the third ingot

microstructure of rapidly cooled ingot two

same

So , we have one more ingot to melt before beginning to work the high carbon material.

.

[Jan Ysselstein]

Ingot 2 is very squat , fired for an hour and is solid not porous. ( see photo above )

Ingot 3 is twice as tall, was fired for an hour and has porosity near the top. Both ingots has a glass addition. ( see photo above )

 

Ingot 4 will run an extra .5 hrs to see if that will allow the gasses to escape. I will try to run it tomorrow. Though not shown here ingot #2 had dark and light areas but seemed completely melted.....hopefully the extra .5 hrs. will address this as well.

Here are some pictures of the microstructure of ingot #3 of this series very rough pics.

 

 

 

[Joshua States]

Cool stuff here.

Thanks for showing this process.

[Jan Ysselstein]

Joshua, Thank you, I love doing this stuff...I may title my next thread ..The XXXXXXXXX Monolouges ..I am actually quite comfortable in that quiet space. This topic has so many opportunities for experimentation and they are all interesting.

 

The last of four cast iron/bloomery iron ingots has ben melted 1.5 hrs at heat, 16 lbs of propane, glass. This ingot is being slow cooled by leaving it in a hot furnace of considerable thermal mass. If all goes well we will treat the metal as Wootz and also fold some of it into a bar of steel. By the way, all four of the ingots are on the high side of Tamahagane and about in the middle for Wootz....we will lose some of that carbon on the way.

 

The last four runs were very interesting..I am sad to be changing that little furnace back to a welding forge again , it has been doing so well. I am ordering some material which will allow me to do the bloomery iron with Carbon..as soon as that comes in, we will give it another attempt. Having been away from the forge for so long my next free times will be spent practicing the welding...I would like to get that to about 6 welds per hour. I will also be reviewing the contents of this thread located in Bloomers and Buttons

Georgian 'Bulat' technology by Zaqro Nonikashvili

Jan

Edited July 26, 2016 by Jan Ysselstein

[Jan Ysselstein]

The fourth ingot is mostly solid but does have gas under the top...I will cut off about 1/4 to 1/3 the ingot and hope the bubbles get removed that way. I will continue with this series for a few more melts but keep that away from this topic. We have enough metal to work with. That system will have to run for a long time so I better fix it now.

 

The ingot weighs 1445 grams, consumed about 16lbs of propane in 1.65 hrs ( of full heat )...I am not sure the crucible would have lasted much longer. I will try to use the 2/3 of the ingot as planned. Here are some pics,

The viewer should compare the microstructures of the fast vs slowly cooled ingots ( in the posts above ).

 

Edit, This ingot is all porous and will be forged into plates..so I will have to repeat it, darn .

 

fourth ingot

fourth ingot microstructure

same

same

Edited July 26, 2016 by Jan Ysselstein

[Jan Ysselstein]

Well, it looks like the forged from an ingot blades ( these are not going to be welded) will come from ingot #2 or ingot #3...#4 is a mess. Tomorrow I will do a run (with an already staged crucible) to get past the porosity problem, it should work.

 

For the next few weeks I will push away and catch up on some other priorities.

 

Jan

[Jan Ysselstein]

THIS IS A SECOND #4, REPLACING WHAT IS SHOWN IN THE ABOVE POST

 

OK , I think we are out of our funk...ingot 4 was made again ( from fresh raw materials ) and it looks very good. The solution seemed to be not running longer but running hotter. I will discard the original #4. The actual carbon content should be just about 1.4% Carbon. Here are some pics of the melt.. The ingot weighs about 1000 grams, 1 hour at high, high heat. The ingot was cooled at an intermediate cooling rate.

 

top of ingot

side of ingot

bottom of ingot

micro structure

 

 

Jan

Edited July 27, 2016 by Jan Ysselstein

[Joshua States]

Now we are getting somewhere.

Where did you get the crucible?

[Jan Ysselstein]

Joshua,

The crucibles are homemade. The crucibles are a project onto themselves. Each crucible is only good for one ingot.

Jan