When Steel components are tempered is it possible during the heat treatment process to allow too much time soaking at the target tempering temperature?
youtectic;
Yes, it is possible. Standard tempering times for most carbon and low alloy steels are 1 hour/inch at tempering temperature with slight incremental increases in time based on thicker components. If you remain too long at a specific tempering temperature you will reduce strength properties from carbide coarsening.
youtectic;
Although, I am not experienced in PM part processing, I believe the parameters regarding time at temperature would also apply to PM parts, based on what I have seen in literature.
The time is a minor function. If the target time is 2 hours you really shouldn't see any difference at 1.5 hours or 3 hours. On the other hand a 50F shift in temperature can have a major impact.
Thanks for your reply Plymouth
I was also wondering if excessve time at temperature could have maybe a detrimental effect on the dimensional stability of small components?
