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Hi guys, so I was making a dagger and did 3 heat cycles at critical temp then quenched and tempered the blade for 3 hours at 350 F I was fitting the handle and guard and I twisted too Hard and the hilt snapped so I lost the blade. I'm attaching to show you my grain structure to see if it was properly treated (so I can learn something from this loss) I broke the blade in half so I could see the structure in the middle as well. Please comment below how you see the structure

I’m currently tempering my tomahawk head at 450 for an hour. Would wrapping it aluminum foil during the temper secure it affect the temper in any way? Sort of a stupid question just making sure because I spent a while on this blade and the handle

Yesterday evening I finished and heat treated my mini tomahawk head made from an old rusted prybar, and it successfully hardened to my surprise. I just did some research on tempering and wish I knew to temper the blade sooner, or that I had time to do it after the quench, but now it's the next morning and I don't know if tempering would be safe. The steel is fine and did not crack overnight and everything seems to be okay, but can critial damage be done during a temper similar to that of a heat treat? I heard 400F for 3 hours, cooling it every hour is the way to go, but this late after a treat I'm not sure how dangerous that would be, any suggestions? Thanks!

I ground my third knife today from a file. The first knife was forged and heat treated, the second was ground and tempered twice at 400 degrees +- 5 degrees. This time I tempered a file three times at 400 degrees +- five degrees for 1 1/2 hours, letting it cool in the oven to room temperature between cycles. I then ground a knife. I tested the file tang before I ground the blade and it easily bent about 30 degrees and then back to zero. I ground the knife and did the brass rod test on the middle part of the blade and it passed at 30 pounds force. The tip failed, staying deformed. The very tip bent with minimal pressure. I put the knife in a vise to see if the body would bend, and it snapped in two. So, what is going on? is this uneven tempering or over tempering, or something else. Also, the tip did not change color during grinding so I do not think it overheated. I would appreciate any help.

I started making a small pen knife from a 3/16 inch thick spring. I got it forged, filed, quenched, and tempered but it snapped when I bent it. today I am going to make another one with more care in quenching and tempering. it was tempered at 450 for 1 hour.

Specifications United States: AISI 6150, AMS 6450, AMS 7301, ASTM A322 (6150), ASTM A519 (6150), ASTM A829, SAE J1397 (6150) , SAE J412 (6150), AMS 6448, AMS 6455, ASTM A29 (6150), ASTM A331 (6150), ASTM A752 (6150), MIL. S-8503, SAE J404 (6150), UNSG 61500 International: DIN 50CrV4, EN 50CrV4, Chemistry Crucible: Carbon 0.50, Manganese 0.80, Silicon 0.30, Chromium 1.00, Vanadium 0.15 Metal Ravne: Carbon 0.51, Manganese 0.90, Silicon max. 0.40, Chromium 1.09, Vanadium 0.18, Metal Suppliers Online: Carbon 0.48-0.53, Manganese 0.7-0.9, Silicon 0.15-0.35, Chromium 0.8-0.9, Vanadium 0.15 min. Principle Design Features 6150 is a fine grained, highly abrasion resistant carbon-chromium alloy steel. Very good shock resistance and toughness are also key properties of this alloy in the heat treated condition. Forging Range Forge between 2200 and 1600 degrees Fahrenheit. Note that welding temperature is around 2300 degrees Fahrenheit. You pretty much want to be forging this stuff at a welding heat and be sure to stop hitting it before it gets too cold. The first heat you take will require a definite soak time, from 10-30 minutes, before you start forging. Critical 1360-1380 degrees Fahrenheit Normalize Cycle 1 - Make it good and hot, around 2200 degrees Fahrenheit, soak 10-30 minutes, air cool. Cycle 2 - Get it to 1600 degrees Fahrenheit, soak 10-30 minutes, air cool. Cycle 3 - Heat to 1550 degrees Fahrenheit, soak10-30 minutes, air cool. Hardening Preheat to 1200-1250 degrees Fahrenheit and equalize. Heat to 1500-1650 degrees Fahrenheit, soak 10-30 minutes. Quench Oil quench to hand warm (150 degrees Fahrenheit). Temper Immediately. Temper 2 hours minimum soak at temperature. Cross sections thicker than 2 inches require 1 hour per inch of thickness, round any fractions up. Knives from 6150 will get tempered cooler than you are used to, Here is a clue from an old post (Tempering 6150) "I heat treated a forged blade made of 6150, quenched it in oil and tempered twice at 375 for an hour each time. It Rc tested at 58." Do your own research! Find out, for yourself, all of the information I left out! Here are links to some of the sources used for the information herein: Crucible Selector - AISI 6150 Alloy Steel Metal Ravne Steel Selector - Steel VCV150 (Mat. No. 1.8159, DIN 50CrV4, AISI 6145/6150) Metal Suppliers Online - 6150 Ally Steel