I made a knife from 5160 spring steel and after I heat treated it and tempered it, I checked the hardness on a Rockwell C tester and the hardness is 57 C. I skinned a deer with it, and it stayed sharp enough to finish the whole deer but would not shave hair and had to be touched up with ceramic stone. Is this typical of this steel with the .6 carbon content ? Would 1080 or 1095 stay sharper ? Thank you for the help.
-
The BladeForums.com 2024 Traditional Knife is ready to order! See this thread for details: https://www.bladeforums.com/threads/bladeforums-2024-traditional-knife.2003187/
Price is$300$250 ea (shipped within CONUS). If you live outside the US, I will contact you after your order for extra shipping charges.
Order here: https://www.bladeforums.com/help/2024-traditional/ - Order as many as you like, we have plenty.
5160 edge retention ?
- Thread starter jones78
- Start date
A.McPherson
Knifemaker / Craftsman / Service Provider
- Joined
- Jan 27, 2012
- Messages
- 2,875
If you took the 5160 up to a higher hardness it would have better edge retention.
Here's a video about edge retention byLarrin
I tempered the knife in the kitchen oven at 350 degrees , three one hour cycles. Do you think maybe two one hour cycles would be better?If you took the 5160 up to a higher hardness it would have better edge retention.
Here's a video about edge retention by
The carbon content of 5160 can vary somewhat, if it’s on the lower end, it will be difficult to get higher hardness. If you are using recycled material, it might not be 5160.
5160 requires precise temperature control, if you are heat treating in a forge, you may be overheating.
A cryo quench will help.
I recommend you try a high alloy steel professionally heat treated.
Highly polished edges don’t last as long as coarser sharpened edges.
Hoss
5160 requires precise temperature control, if you are heat treating in a forge, you may be overheating.
A cryo quench will help.
I recommend you try a high alloy steel professionally heat treated.
Highly polished edges don’t last as long as coarser sharpened edges.
Hoss
- Joined
- Jan 1, 2011
- Messages
- 196
I made a hunter out of O-1. Used it and another knife to process an elk. It made it through a good portion of the elk, but the part of the edge doing most of the cutting was dulled. Still could make it work, but a touch up made it work better.
You can read about people making it through many deer without sharpening. Makes me think of when I helped my buddy with his last deer. He was very happy with the edge on the knife he was using (D2). I took out my 10v hunter that was very sharp and swapped knives. His was very dull by comparison. Still was making it through the deer, and he was happy with it, until he used a fresh edge.
The biggest jump in performance I’ve had is when I went from a forge heat treat to an oven.
I’m not surprised your 5160 knife needed a touch up, higher carbon should be a little better, but I’d bet you are still going to want to sharpen it between animals if you enjoy a good edge.
You could also thin the edge down if it isn’t already very thin.
You can read about people making it through many deer without sharpening. Makes me think of when I helped my buddy with his last deer. He was very happy with the edge on the knife he was using (D2). I took out my 10v hunter that was very sharp and swapped knives. His was very dull by comparison. Still was making it through the deer, and he was happy with it, until he used a fresh edge.
The biggest jump in performance I’ve had is when I went from a forge heat treat to an oven.
I’m not surprised your 5160 knife needed a touch up, higher carbon should be a little better, but I’d bet you are still going to want to sharpen it between animals if you enjoy a good edge.
You could also thin the edge down if it isn’t already very thin.
Stacy E. Apelt - Bladesmith
ilmarinen - MODERATOR
Moderator
Knifemaker / Craftsman / Service Provider
- Joined
- Aug 20, 2004
- Messages
- 37,978
I agree with all the others.
Do yourself a BIG favor and get yourself a copy of Larrin's book, "Knife Engineering." It will show you the different attributes of most all knife steels in the charts. Picking the steel for the task is how you make the best knife. What works in the kitchen doesn't necessarily work on a deer.
5160 is a fine steel for learning forging and makes a perfectly good general use or EDC knife. But for a knife used in the kitchen or a knife sued to dress game, it will not hold an edge for long.
Now, as to the tempering, Yes, you need a second temper ... on all knife steels. Here is part of one old post I made on tempering:
After the quench you need to immediately temper the steel once it cools to room temperature ( or after sub-zero or cryo treatment)
Immediate means as soon as is practical (not necessarily withing seconds or minutes). When a blade comes out of the quench, it is under extreme internal stress. It is also composed of very brittle untempered martensite. It can shatter, or crack easily, sometimes just sitting there, but surely if it is struck or dropped. The sooner it gets into the temper oven, the better. If doing several blades,set each aside laying flat on the bench until all are done. Carefully and gentle wash off all oil and put the batch into the oven to temper. Minutes or even an hour or two isn't necessarily a death sentence for the blade, but leaving around overnight or longer is asking for trouble. If you can't do a full temper immediately, do a snap temper at 300 or 350 for 30 minutes. When you have time do the standard two tempers.
(For plain carbon steels) When steel is quenched, the austenite that formed at 1400-1500F (called the A1 point) is converted to martensite. This conversion starts at about 400-450F (called the Ms). It finishes somewhere between 200F and room temperature (called the Mf). Thus, the steel must drop to room temperature before temper, so the conversion can be completed .The small amount of austenite that remains (retained austenite) is converted when the steel is heated back up to near the martensite start point again and then cooled back to room temperature. This new small amount of martensite is untempered, which is why you do two temper cycles. The second cycle tempers out the new martensite, and makes sure that the temper is evenly distributed.
(Note: On complex alloy steels, like stainless, the Mf can be 100F below zero. It takes a sub-zero or cryo treatment and two or three tempers to convert all the austenite to martensite. This is why cryo is recommended for such steels.)
As to temper times. Yes, you can temper with a torch in one or two minutes by drawing the blade spine and watching the colors, but it will be a very uneven and incomplete temper.A proper temper takes time.
The movement of atoms in steel is rapid at 1500F, but very slow at 400F. It takes at least an hour or more to allow the changes in structure to occur in the steel to get a good temper. The second temper finishes the job. While one ,one hour temper will do most of the job - two , two hour temper cycles is a much better procedure.
Tempering is the movement of atoms, and as said, that takes time. The temperature allows this to happen, so the temper cycle is a function of time and temperature. Raise the temperature and it happens faster, do it longer and it happens more. Of the two, temperature is the active factor. The ratio of temperature to time in activity is about 10:1. That means a small increase in temperature will have ten times the impact on the hardness than a moderate increase in time. For practical purposes, assuming the temperature to be constant, a four hour temper would not appreciably lower the hardness (maybe less than one point), but a ten degree increase in the temperature may affect it 1-2 points. This is why knowing the true temperature swings of your oven is important. If your home oven is set on 400F, that is the average that it is at. It may heat up to 425F and drop to 390F before the heat cuts back on during each heat/cool cycle. For accurate tempering a controlled oven is what you want. You can build one from a good quality countertop oven. These ovens are often very cheap at thrift shops.
Stacy
Do yourself a BIG favor and get yourself a copy of Larrin's book, "Knife Engineering." It will show you the different attributes of most all knife steels in the charts. Picking the steel for the task is how you make the best knife. What works in the kitchen doesn't necessarily work on a deer.
5160 is a fine steel for learning forging and makes a perfectly good general use or EDC knife. But for a knife used in the kitchen or a knife sued to dress game, it will not hold an edge for long.
Now, as to the tempering, Yes, you need a second temper ... on all knife steels. Here is part of one old post I made on tempering:
After the quench you need to immediately temper the steel once it cools to room temperature ( or after sub-zero or cryo treatment)
Immediate means as soon as is practical (not necessarily withing seconds or minutes). When a blade comes out of the quench, it is under extreme internal stress. It is also composed of very brittle untempered martensite. It can shatter, or crack easily, sometimes just sitting there, but surely if it is struck or dropped. The sooner it gets into the temper oven, the better. If doing several blades,set each aside laying flat on the bench until all are done. Carefully and gentle wash off all oil and put the batch into the oven to temper. Minutes or even an hour or two isn't necessarily a death sentence for the blade, but leaving around overnight or longer is asking for trouble. If you can't do a full temper immediately, do a snap temper at 300 or 350 for 30 minutes. When you have time do the standard two tempers.
(For plain carbon steels) When steel is quenched, the austenite that formed at 1400-1500F (called the A1 point) is converted to martensite. This conversion starts at about 400-450F (called the Ms). It finishes somewhere between 200F and room temperature (called the Mf). Thus, the steel must drop to room temperature before temper, so the conversion can be completed .The small amount of austenite that remains (retained austenite) is converted when the steel is heated back up to near the martensite start point again and then cooled back to room temperature. This new small amount of martensite is untempered, which is why you do two temper cycles. The second cycle tempers out the new martensite, and makes sure that the temper is evenly distributed.
(Note: On complex alloy steels, like stainless, the Mf can be 100F below zero. It takes a sub-zero or cryo treatment and two or three tempers to convert all the austenite to martensite. This is why cryo is recommended for such steels.)
As to temper times. Yes, you can temper with a torch in one or two minutes by drawing the blade spine and watching the colors, but it will be a very uneven and incomplete temper.A proper temper takes time.
The movement of atoms in steel is rapid at 1500F, but very slow at 400F. It takes at least an hour or more to allow the changes in structure to occur in the steel to get a good temper. The second temper finishes the job. While one ,one hour temper will do most of the job - two , two hour temper cycles is a much better procedure.
Tempering is the movement of atoms, and as said, that takes time. The temperature allows this to happen, so the temper cycle is a function of time and temperature. Raise the temperature and it happens faster, do it longer and it happens more. Of the two, temperature is the active factor. The ratio of temperature to time in activity is about 10:1. That means a small increase in temperature will have ten times the impact on the hardness than a moderate increase in time. For practical purposes, assuming the temperature to be constant, a four hour temper would not appreciably lower the hardness (maybe less than one point), but a ten degree increase in the temperature may affect it 1-2 points. This is why knowing the true temperature swings of your oven is important. If your home oven is set on 400F, that is the average that it is at. It may heat up to 425F and drop to 390F before the heat cuts back on during each heat/cool cycle. For accurate tempering a controlled oven is what you want. You can build one from a good quality countertop oven. These ovens are often very cheap at thrift shops.
Stacy