Heat Treating, general discussion

for some bundle we quenched in water and oil, the structure has ferrite with martensite and bainite. austenitizing temp. 860C Holding time: 60 min Dipping time:300 seconds moving time: 100seconds has anyone knowledge about existence of ferrite in quench microstructure?

I need 27 j impact energy at -20C temp. for s235j2 (C:0.1- Si:0.04- Mn:0.45- P: 0.025, S: 0.02) what heat treatment cycle is good for this steel?

Hey everyone! I have an odd and out of the blue question about tempering, so just humor me for a second. I'm writing a story with a blacksmith protagonist who fails at tempering, so all his products end up brittle. I've heard of this brittleness happening as a result of bad tempering, but I have no clue as to how one does it--and just HOW brittle can the metal get? Thanks!

I am starting this new thread on pyrometers as I believe that there is much interest in accurate temperature measurement in heat treating. I have a thermocouple pyrometer which reads to 2000 degrees F. which I have used in a brick pile forge. I have very successfully used this pyrometer in heat treating some pipe notching dies which I machined out of O6. I heated the dies in molten salt (common rock salt). I inserted the thermocouple probe into the molten salt along with the suspended die and when the temperature rose to the desired hardening point I reduced the flame and let the steed die soal a little toallow the die to come up to the temperature of the salt bath. …

I have a pry bar that i broke one of the nail pulling ears off of. I thought it would make a great blacksmithing project to cut off the other ear, and reform the nail puller jaw. the question is. how is the standard crow bar, or pry bar heat treated? (this is the standard 6 sided hex bar with a more than 90deg bend on the nail puller end and a slight bend on the other flatened end) Are these heat treated? I would think air quench would mean the steel is to soft for prying, but water quench would make it to brittle and subject to fracture especially when being beat on with a hammer.

A man at work was talking about aguy he knows who uses dry ice in his tempering process. I have never heard of this or seen it discussed on here. I did some reading on it last night,it's apparently very effective. I guess you could call it cold treating.

I started with a piece of 7/8 O.D 4130 chromoly tube. Had them bent to make a pair of bicycle handle bars aprox 30" width and 4" rise. The bars bent the first day about 7 degrees at the first bend. My thoughts are to heat treat again after the bending process. Things Ive read and heard from fellow small time manufacturers, heat up the furnace, home oven in my case, to about 450-500 degrees F. let bake for 20minutes and then dip in motor oil to seal the heat process. This is a final touch to the handlebars before production levels. I need to know if this process can harden the chromoly just enough to hopefully prevent bending again. thanks, G

Hi everyone, I thought I'd use this post to introduce myself. I started smithing about three months ago. As I began messing around, I quickly found out what the term "burnt iron" was. I work in the lab of a grey/ductile iron casting foundry in NEPA, under a fantastic and very experienced metallurgist. He has been helping me along throughout my progress, but with my question concerning burnt iron, he couldn't help (he had never heard the term). So last weekend, while working in the forge, I purposely burnt the end of a rod, bringing it to its liquidius temp (honestly didn't think I could do that). I cut two pieces: one burnt and one untouched. The microstructure …

I just read an article by Dave Smucker on Heat Treatment of Tool Steel. As I was reading it, I was wonder if there is a minimum temperature that tool steel needs to reach to forge weld for a blacksmith with a 3 lb hammer and anvil. I would image that at room temperature it would be impossible to weld two pieces of tool steel together by hand. However, as the steel is heated, is there a grain structure that is reached that allows for forge welding to take place with less stress and deformation? Or, do we want to reach a certain grain structure before forge welding? Do we want to forge weld at a specific grain structure. Dave indicated that after forging we don't want …

I'm making an anvil bridge tool from a piece of 5160 to sit in the hardy. How far should I temper it? Obviously I don't want it to bend with use, but hammering in the middle of the bridge would be likely to cause cracking if it was too hard. Any suggestions? I'd imagine it wants to be a bit softer than an anvil face.

Is is feasible to achieve certain temper colors by using a household oven? For instance, if I want my wizard bottle opener to be a nice shade of blue can I achieve a nice even blue hue using my kitchen oven?

Fellows, I looked over the anvil forum, and this seemed a better place to put this. I've been corresponding with a good friend of mine for some time now on the relative merits of making your own anvils. It just so happens that several years ago I was the Safety officer on a large industrial construction project, and aquired several small pieces of 4140 plate in 2", 3", and 4" thickneses, in addition to a 6" diameter by 16 inch length solid cylinder of the same material. In our most recent conversation, (which also included ruminations on building a "B" bore (one inch bore) wall gun from high pressure fracking pipe, and the need for a rifling bench if we were to do so,)…

I've read that car spring steel and steel of a similar carbon content shouldn't be heated above red/orange, if it has been is there any way of undoing the mistake? Higher carbon steel feels a lot harder to work with than mild steel, logic says heat it up more so it's easier to work with but if I shouldn't heat it up beyond red/orange, is hitting harder my only option?

Hi friends, I want to make a diamond awl for leather stitching. The awl blade needs to be very strong so as not to bend or break while pushing it through fairly thick leather, so whatever metal I use, I am planning on heat treating it... A few questions... --Would 1084 or 01 steel be better to use for making an awl? --What would the basic heat treat workflow look like for 1084 or 01? Thank you in advance for your time and expertise!!!

My steel yard has volumes of 4150 tool steel in a usable size. I typically use spring steel or 4140 for making top & bottom tools, tongs, and hammers. My question is, can I exchange 4140 for 4150? If so, what is the difference in the two metals. I'm guessing 4150 has more carbon and would require a higher temp range for tempering. Am I right? Can it be cooled the same? Thanks!

My style of blacksmithing could be classified as " Rural Circa 1850 " as apposed to "ASME Circa 2012" . Is there a rule of thumb as to how much oil is needed to safely and effectively quench a given weight of steel. Now I know this question may be a little vague, but I'm using junkyard leaf and/or coil springs and the parts to be quenched will be in the range of a few ounces up to a maximum of about two pounds. I can not keep the oil at the forge so I expect to bring the oil to the forge and remove it after I use it. I know there are oils specifically made for quenching steels, but what did blacksmiths use a hundred years ago, before these were invented. W…

i have heard of double and triple tempering, tempering, shining, re-tempering etc, and have been told that the longer the steel is held at the tempering temp, the more effective it is? has anyone got any more in depth explainations? thanks monty

We machine some parts from 4140A. For wear resistance, they need a harder face. Obviously there are probably better materials and processes for face hardening but these parts are less than 1" cubed so hard to not full harden then anyway. We originally made these from 4140HT which is HRC 28-32. That is really not hard enough but we were trying to avoid the process. We found that we needed the Annealed condition for easier machining and further have been hardening them with a torch and oil. each is carefully heated to just when they glow a bright orange. Th process has been getting them to about HRC 50 which is about spot on. It is my understanding that 4140 can a…

We have a 80 pound steel casting (0.3% C max, 1.85%Mn max, Si 1.5% max) that is quenched and double tempered. Is there a test (hardness, microstructure, etc.) we can do to determine if it was double tempered or tempered just once?

Has anyone here taken any of the ASM online courses? Specifically I am looking at "Metallurgy for the Non Metallurgist" and "Heat treatment of steel". I feel I should get a better understanding of heat treatment for some of the work I am doing and so I have a better understanding of metallurgy when I am talking to engineers. As well I would like to get a better understanding of the phase diagrams in the heat treaters guide. The courses are not cheap so I am wondering if I would learn just as much by buying the books they have with the same titles. Or is there more or better presented information in the courses? Of course there may be something to be said for the …

Hello, all, The coil spring in the 300A work clamp for my welder recently broke, and since I have some 5/32" spring steel that's almost the exact same diameter as the wire used in the original spring, I figured I'd give it a try. (I just knew the springs from that old bed boxspring would be useful for SOMEthing!) Anyway, I'm a complete novice at blacksmithing, and just wanted to check with you folks for any tips on making this spring. In general, I plan to: 1. Heat the spring material to cherry red to shape it 2. Quench in oil 3. Temper to about 700°F The main questions I have are: 1. Should I heat the spring material to critical temperature and allow it to …

Bought a TD6 PID controller for a tempering oven. The english syntax in the 'manual' is so bad as to be totally useless. "In display estate press SET,P/MV lamp on means SV setting while off means MV manual output setting but only on manual operation and input connect do MV settable" I can set the target temp and that's all. I need to change from celsius to fahrenheit. I'd like to set a ramp speed for cooling but can live without it. Any help would be appreciated. Keith

I am making some parts from A36 that are riveted together and using super quench trying to hardIT a little. My question: Since it has a lot of salt in it am I going to run into a corrosion problem later? - How are any other users of this cleaning up your parts? Thanks for any help folks -- Bill

I coulda added on to the 4140 topic but would like to start my own here. There's two steels Grant turned me onto; 4140 as used in Off-center's swage dies (why doesn't someone ask what hardening method Kayne uses now?) and 8630. Similar to 4140, this stuff is supposed to be oil hardening. Similar to 4140, achieved hardness with oil quench leaves alot to be desired. Grant mentioned about water for thicker sections of 4140 and I would now concur. Unfortunately I never got to ask him about water quenching 8630. References list both methods and I'm wondering what you guys have used. The dies I've made have differing sections of mass that I'm afraid may stress out. I water …

Hi folks, I'm heating a #4 Morse taper lathe center as I type this. As a machine operator my understanding of the hot side of metal working is very limited. So if any one would like to comment on what I'm doing here i would be glad to read what you have to say. I started with a #4 dead center that had been abused to the point that, well there was no point the 60* taper was blunt to about 5/16" so I turned a new point on it and could tell that it was way harder near the O.D. than near the center. I don't know what it is made of but it is not rusty after many years of laying around (other parts that were stored with it are). It was pretty hard, I had to run the spindle bet…