Hi all
There is a knife in planing stage atm from 1.2767 / Boehler K600
http://www.bohler-edelstahl.com/files/K600DE.pdf
Reading the data sheet i thought the heat treatment process has to look something like this :
Heat treatment K600 (26.05.2013)
- Smithing:
Forming the main shape
- normalizing (4 cycles):
a) at 750°C, hold time 5 min, cool down slowly
b) at 750°C, hold time 5 min, cool down slowly
c) at 750°C, hold time 5 min, cool down slowly
d) at 750°C, hold time 5 min, cool down slowly
- sharp Normalizing (3 cycles):
a) At 800°C, hold time 1 minute, quench in warm oil (about 40°C)
b) At 800°C, hold time 1 minute, quench in warm oil (about 40°C)
c) At 800°C, hold time 1 minute, quench in warm oil (about 40°C)
- Annealing:
a) at 660 °C letting it cool down *very* slowly to 600°C in the oven (~4h)
b) then let it cool down at room temperature
- Polishing/Grinding:
Removing scale and the first grind to give the form to the blade and tang
- Stress reduction:
a) heat slowly to 640°C temperature
b) hold for 3 hours, letting it slowly cool down to room temp
- Hardening:
a) heat to 450°C, hold time 5 minutes
b) heat to 650°C, hold time 5 minutes
c) heat to 840°C, hold time 10 minutes, quench in warm oil (about 40°C)
- deep cooling (as soon as possible after quench):
1) crushed ice cubes from freezer, salt and pure alcohol (~ -20°C)
2) quench blade, hold time about 10 minutes
- grain material test:
breaking the test pieces of steel in a vice and checking the grain structure
- Tempering (as soon as possible after deep cooling):
1) at 200°C for 2 hours (1st cycle)
2) quench in water immediately
3) at 200°C for 2 hours (2nd cycle)
4) quench in water immediately
5) at 200°C for 2 hours (3rd cycle)
6) quench in water immediately
- Stress relieving (as soon as possible after last temper):
1) at 170°C for 2 hours (3rd cycle)
2) let it cool at room temperature
- final shaping and sharpening on wet grinder
Full height Convex edge
I think it should result in something like 56 HRc after heat treat.
Can you guys give me any pointers if this is correct, or if i am totally off target with this.
Thanks a lot in advance.
Yours sincerely,
me
There is a knife in planing stage atm from 1.2767 / Boehler K600
http://www.bohler-edelstahl.com/files/K600DE.pdf
Reading the data sheet i thought the heat treatment process has to look something like this :
Heat treatment K600 (26.05.2013)
- Smithing:
Forming the main shape
- normalizing (4 cycles):
a) at 750°C, hold time 5 min, cool down slowly
b) at 750°C, hold time 5 min, cool down slowly
c) at 750°C, hold time 5 min, cool down slowly
d) at 750°C, hold time 5 min, cool down slowly
- sharp Normalizing (3 cycles):
a) At 800°C, hold time 1 minute, quench in warm oil (about 40°C)
b) At 800°C, hold time 1 minute, quench in warm oil (about 40°C)
c) At 800°C, hold time 1 minute, quench in warm oil (about 40°C)
- Annealing:
a) at 660 °C letting it cool down *very* slowly to 600°C in the oven (~4h)
b) then let it cool down at room temperature
- Polishing/Grinding:
Removing scale and the first grind to give the form to the blade and tang
- Stress reduction:
a) heat slowly to 640°C temperature
b) hold for 3 hours, letting it slowly cool down to room temp
- Hardening:
a) heat to 450°C, hold time 5 minutes
b) heat to 650°C, hold time 5 minutes
c) heat to 840°C, hold time 10 minutes, quench in warm oil (about 40°C)
- deep cooling (as soon as possible after quench):
1) crushed ice cubes from freezer, salt and pure alcohol (~ -20°C)
2) quench blade, hold time about 10 minutes
- grain material test:
breaking the test pieces of steel in a vice and checking the grain structure
- Tempering (as soon as possible after deep cooling):
1) at 200°C for 2 hours (1st cycle)
2) quench in water immediately
3) at 200°C for 2 hours (2nd cycle)
4) quench in water immediately
5) at 200°C for 2 hours (3rd cycle)
6) quench in water immediately
- Stress relieving (as soon as possible after last temper):
1) at 170°C for 2 hours (3rd cycle)
2) let it cool at room temperature
- final shaping and sharpening on wet grinder
Full height Convex edge
I think it should result in something like 56 HRc after heat treat.
Can you guys give me any pointers if this is correct, or if i am totally off target with this.
Thanks a lot in advance.
Yours sincerely,
me