dognose Posted January 17, 2014 Share Posted January 17, 2014 My question has to do specifically with drawing a temper. I think I have a clear grasp on all the procedures up to the final step. In previous posts, there has been mentioned drawing a temp of approx a 1,000 degrees and holding it there for the required time (depending on thickness) and then a gradual controlled cooling. I have access to a small programmable kiln, so I am able to do so. One of my questions is, if I use this method, it seems the tool will have the same hardness throughout, from end to end. All my experience with drawing tempers on other tool steels involves leaving the struck end of the tool in a softer state that the working end. I ask because I'd like to avoid marring the face of my hammer if possible, or is it better to just use a sacrificial hammer for striking hard hand tools? I've made H13 chisels before where I just slowly heated the working end with a rosebud to a yellow and then quenched them in oil. So far, those tools have held up well, I'd just like to be better informed and make tools the best way possible. Many thanks. Link to comment Share on other sites More sharing options...
ThomasPowers Posted January 17, 2014 Share Posted January 17, 2014 High alloy tool steels are often "different" and do not play by the normal rules. (eg S-1 does not profit from normalization) Perhaps one of our metallurgists can address the specifics for H13? Patrick? Link to comment Share on other sites More sharing options...
Rich Hale Posted January 17, 2014 Share Posted January 17, 2014 I have made a lot of struck tools from H 13....The books or charts do not mention wot I do. i will share and if you like you use and see if it fits wot you do. I do the same thing for S 7 Forge to final shape. Heat to non magnetic and put in a bucket of vermiculite overnight to anneal. Next day finish the piece as you wish ,,grind etc. Then heat the working end to non magnetic in a coal forge...lay it out of the way until it cools...If youi lay the hot end on anything it will lose its heat fast...You can put other end in a vise or lay off edge of bench etc. If it has a hole you can hang with wire . Link to comment Share on other sites More sharing options...
EricJergensen Posted January 17, 2014 Share Posted January 17, 2014 The key is only heating the working end to the hardening temperature after you anneal. That way the struck end does not harden. You could just put the struck end in your vice and leave it until it cools (what Rich said). Temper right after it cools. Two tempering sequences is recommended. 1) forge 2) anneal (in the kiln) 3) grind, file, etc 4) harden working end 5) temper Link to comment Share on other sites More sharing options...
Rich Hale Posted January 17, 2014 Share Posted January 17, 2014 i do not temper the tools i outlined the ht above..and for a logical reason..Both of these steels are hot work steels..They deform little at all even when the get to a dull red heat...that would take away efforts to temper them as the red would be higher temp than tempering heat.. I do use these as hot punch tools and at times they get to the dull red... Link to comment Share on other sites More sharing options...
ThomasPowers Posted January 17, 2014 Share Posted January 17, 2014 Some alloys dull red is tempering temp! Link to comment Share on other sites More sharing options...
Rich Hale Posted January 17, 2014 Share Posted January 17, 2014 In the right light... :) Link to comment Share on other sites More sharing options...
Stephen Olivo Posted January 17, 2014 Share Posted January 17, 2014 Interesting my friend just gave me a peice of h 13 and I have to research it. Thanks for info. Link to comment Share on other sites More sharing options...
ThomasPowers Posted January 18, 2014 Share Posted January 18, 2014 don't work it too hot---you can cottage cheese it! Link to comment Share on other sites More sharing options...
rthibeau Posted January 18, 2014 Share Posted January 18, 2014 H13 is an air hardening steel when used for struck tools. Buy it annealed or anneal it yourself then forge the business end to the desired shape......clean it, grind it, when all done heat just the working end to nonmagnetic and let it air cool. The struck end will be annealed and the working end will be tempered, as it were. In use, do not quench, let air cool. Link to comment Share on other sites More sharing options...
thingmaker3 Posted January 19, 2014 Share Posted January 19, 2014 Non-magneic is not hot enough to austenitize H13. Get a kiln or get another steel. (And yes, I know "Famous Smith" uses non-magnetic. It still isn't hot enough.) Link to comment Share on other sites More sharing options...
Frank Turley Posted January 20, 2014 Share Posted January 20, 2014 I'm using a color chart*, assuming we all may see incandescence differently, and assuming that we're looking at color in ordinary shop light, not sunlight. Tool steels are normally delivered annealed in 12' lengths. If the H13 is annealed as delivered, you can cold cut it to length with a saw or zip disc in order to preserve the anneal. On an end-to-end tool, one with a business end and opposite it, a striking head, do not forge or heat the striking end, again to preserve the anneal. Forge only the business end at 1900-2000F (bright orange), Stop at 1650F (bright red, above cherry red) and reheat. It is desirable to anneal after forging, but in a small shop situation, it is difficult to follow the recommended directions, because we are supposed to lose 40 degrees per hour. We don't have that much control. In my shop, I heat to 1550-1650F (bright red) and cool slowly in a dry lime/wood ash mixture. On alloy steels like H13, the non-magnetic thing doesn't always coincide with hardening. Do what the metallurgist says. Heat to 1800-1850F (orange) and cool in still air. Place it while cooling on a non-reactive material, as a fire brick, graphite block, or pile of coke. Don't place on metal, or you'll get a hard zone at the contact point. Harden only the business end. Temper at 1150F (blood red, just above dull red). Getting to your initial question, I am not a metallurgist, but here's what I think. If you've preserved the manufacturer's anneal, you can heat the entire tool to a blood red in your kiln and let it cool without hardening the striking end or affecting it adversely. *Metals for Engineering Craftsmen, London. Rural Industries Bureau, 1964. Link to comment Share on other sites More sharing options...
dognose Posted January 21, 2014 Author Share Posted January 21, 2014 In the manual pictured, there are charts/graphs showing the temps for normalizing, annealing, hardening, quenching and tempering various types of steel. For H13 under Quenching, the term (do) is used. All the other methods mentioned for different alloys I can understand, such as air, oil, brine or water. Nowhere in the book can i find what the letters (do) stand for. Anyone? Link to comment Share on other sites More sharing options...
Jim Kehler Posted January 21, 2014 Share Posted January 21, 2014 I think it stands for "ditto" as in same as above. Link to comment Share on other sites More sharing options...
rthibeau Posted January 21, 2014 Share Posted January 21, 2014 so what is the temperature of H13 at the nonmagnetic point?? just asking, I don't know Link to comment Share on other sites More sharing options...
ThomasPowers Posted January 21, 2014 Share Posted January 21, 2014 it is interesting to note that the Metals Handbook, (ASM) Vol 2 Heatreating indicates that H13 is *harder* when when tempered at 1000 deg F than 200 degrees to either side. It is also harder when quenched in air from 1950 than 1800 degF. We blacksmiths tend toward rough and ready methods but the high alloy steels are at their best when handled very precisely! (I really must save up my pennies and get an optical pyrometer...or go visit someone who has one....) Link to comment Share on other sites More sharing options...
ThomasPowers Posted January 21, 2014 Share Posted January 21, 2014 most steels it's around 1450 degF IIRC have to dig deep to find the curie temperature of H13 Link to comment Share on other sites More sharing options...
patrick Posted January 31, 2014 Share Posted January 31, 2014 This is kind of big topic as are most of those related to metallurgy. Let's first draw a distinction between steels used for tools and steels designated as tool steel by industry. For example, 4130 is often used for tools by some blacksmiths and it is very effective, but by industrial standards it is NOT a tool steel. Next, we need to break down the industrial tool steels into catagories since there are so many. It is unfortunate that the industrial designations are not uniform in their approach. Some are based on quench media generally used, some based on primary alloying elements and some based on intended service. The challenging thing is that many cross over more than one category. Those which are relatively low in alloy content have lower austentizing temperatures and also lower tempering temperature. Included in this group are the W, O, and L series tool steels. All of the remaining types are going be fairly high in alloy content, high in austentizing temperature and tempering temperature and will be air hardening in the section size used by blacksmiths. H13 specifically is alloyed to maintain its hardness at high temperature. To accomplish this, the alloying elements must be dissolved in the austenite during the austenitizing process. Because these alloying elements form complex iron/carbon/alloy compounds, the tempers and TIMES needed to dissolve them are much high than what is need for steels which only form iron carbides. These complex carbides and their dissolution temperature is what requires the use of austenitizing temps of 1850 F or more. If the entire tool is heated to forging temperature during forging, then you absolutely will get a fully hardened tool. If you start with annealed material and only heat one end, you can successfully maintain a soft striking end. Because of the high temperatures (1000 F or more) and very slow cooling rates needed to anneal this grade, it is very difficult to soften one end once you have the entire tool hard. You can however do a couple of things to get around this. 1. Grind the striking end with a generous radius. 2. Use a soft faced hammer. 3. Temper the entire tool to the hardness you want. Keep in mind that H13 will not get as hard as other grades-only to the low 50s HRC. This is not much different from an anvil face. If you don't need the maximum hardness but can live with something in the upper 40s HRC then temper the tool to get that hardness. For H13 that is going to be well in excess of 1000 F as Thomas mentioned.This has the advantage of adding a bit of toughness, but it also means you can get the working end of the tool that much hotter in service before it begins to be affected. If you have access to a furnace that can do this, I'd recommend this approach. 4. Depending on the tool geometry, you may be able to make a sleeve of soft steel to fit over the striking end. Any time you can get access to proper heat treating resources, you should take the time to use them and make your high alloy tool steels uniform in hardness (assuming they were completely heated to forging temp) since this gives you the most control of the final out come and tool performance. Differential forging and heat treat of high alloy tool steels can work, but it is not very controllable or predictable so you do assume more risk when using this approach. This is because the temperatures involved are so high that they cannot be easily judged by color in the same way that you can "run" colors from about 300F-550 F on a shiny piece of steel. With H13 you are dealing with tempering temps that are 1000-1200 F, depending on the hardness you need. That range is pretty tough to judge by eye. All that being said, when I use H13 it is often in the as-forged condition with no further heat treatment. Exceptions to this are my cut off hardy and if I ever get around to it, a set of power hammer dies. These tools I would absolutely have heat treated under controlled conditions. Link to comment Share on other sites More sharing options...
Stephen Olivo Posted January 31, 2014 Share Posted January 31, 2014 just curious after reading all that why with the cut off would you choose to temper? Link to comment Share on other sites More sharing options...
Steve Sells Posted January 31, 2014 Share Posted January 31, 2014 because untempered martinsite is brittle and asking for trouble. Link to comment Share on other sites More sharing options...
Stephen Olivo Posted January 31, 2014 Share Posted January 31, 2014 I understand that. I meant as before stated just forge and use and then there he adds for those things tempering them so I was just curious as to why the choice to temper some and not others with h13. Link to comment Share on other sites More sharing options...
gearhartironwerks Posted February 1, 2014 Share Posted February 1, 2014 H13 as per Grant Sarver: Forge Soak at 1900 for 1 hr. Quench in OIL Temper 1hr at 1000 deg Awesome for hot work. John Gearhart Ironwerks Link to comment Share on other sites More sharing options...
patrick Posted February 1, 2014 Share Posted February 1, 2014 I chose to heat treat the cut of hardy because it will see the most severe use of any tool made from H13 in my shop because I use that tool as both a hot cut and a cold cut. With the right combination of tool geometry and hardness you can do that. If I chose not to heat treat the tool and just use it in the as-forged condition, I would limit its use to hot metal only due do the relatively brittle nature of the as forged material. I make punches for as well as hacks for use under my power hammer from as-forged H13 and they work great, but I'd never use them on cold material the way I do with the anvil hardy. Link to comment Share on other sites More sharing options...
Stephen Olivo Posted February 1, 2014 Share Posted February 1, 2014 Thank you patrick that answered my question. Heavy use and cold cutting. Link to comment Share on other sites More sharing options...
Stefflus Posted February 1, 2014 Share Posted February 1, 2014 What are you cold cutting, H13 isn't the hardest of steels? Edge angle? Link to comment Share on other sites More sharing options...
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now