making die for stainles steel tube flaring and inversion

Can anybody recommend the tools for machining a series of cold work die with
different fillets for 2.5 in tube inversion.
I've been thru a experimental procedure in the handbooks but that didn't
have any data about tools for making angles and radius. As I
understand it, there is a critical radius in which should increase while
angles are increased
I want to see the possibility of making these on one single tool, starting
at the highest angle for different radius
then change the old one to new angle and so on, any help is appreciated.
This want me for my Dissertation and i want to see the effect of punch
radius between 2 and 15 mm as well as
punch apex. angle between 60 and 85 degree.
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Stainless ie 304, 304L, & 316 are really nasty in this application. The radius of the die is strongly dependent on the speed and style (straight, rotary, hammer, combination) with which you actually do the forming. To make matters worse, the stainless has a slight 'memory' that lets the metal creep back towards it's old shape over a few days. It will pass inspection at the machine, won't pass inspection at the customer's place a few days later. (Ask me why I know!)
Ali wrote:
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You may want to get a competent die designer/maker to work on this with you. The reason there are die makers and not just engineers and machinists is because design goes only so far. Someone who is unfamiliar with how a metal _actually_ flows may get stuck on a matter seen as trivial to a seasoned die maker.
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Robin S.
Thanks for helping, considering about the memory in the stainless while inspection i wonder the reasons for backward relaxation is about creep In this case at the very beginning i am doin a routine simulation with a computer program Deform for reducing such risks and simply with one mouse clicking ! and really intersted about the reason why it behaves like this
About the possibility of making a series of dies I wonder if our machinist agree with me because it is his responsibility to make it in the range which has been already designed because the die after heat treatment are not machinable even if it is not hardened it shows abrasion and is out of our agenda
regards, A.R
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