Question:
I think someone here might be able to help me... It is
recommended by a steel spring wire manufacturer that immediately after
coiling, the springs should be stress relieved at about 400°C.
(750°F.) for 30 minutes. If one doesn't have an oven that can heat
something that high, can the springs be heated at a lower temp for less
time? or does heat treating not work like this?
Answer:
Normaly not. But I remember that I have read different numbers like
350°C for 2 or 3 hours. As it is a stress relieve tempering, getting as
close to the required heat and considerably _increasing_ (NOT reducing!)
time should work. But also, the temperature depends on the steel used.
Perhaps within reason, but the time required will probably become
impractical if you deviate very much from the prescribed temperature.
750F sounds very high for normal spring materials. Are you using
something unusual?
Lower temp for longer time. But you ought to be able to find a
suitable oven. Ceramics kiln? It is pretty easy to put together an
oven from insulating firebrick and nichrome that will go to 400 C.
Ceramic kiln go to about 1000 C.
