INCONEL 625 Sheetmetal parts bending 1

[lukaszsz]

Hello everyone,

I'm facing difficulties to find what are minimum allowable dimensions of bent part made from INCO 625

I've made some quick sketch with 1/2 of symmetrical cross-section

Depth, H_offset and stock thickness are determined
What I'm looking for is any source that could provide me minimum bend radius, slope angle and minimum length of offset for INCONEL 625 part

Thanks for Your help, Lukaszsz

LukaszSz. Poland, Warsaw University of Technology, Faculty of Power and Aeronautical Engineering : MEchanical Engineering. BsC - 2013

 

[ctopher]

I think inside bend radius should be equal to material thickness.
Check out this doc. Link

Chris, CSWA
SolidWorks 13
ctopher's home
SolidWorks Legion

 

[MikeHalloran]

Is that half of a U-shaped straight part,
or is it half of a round drawn part?

If it's a drawn part, it appears to be a rather deep draw. ... and the tapered side makes the draw more difficult. Of course, absent dimensions, I have to guess, and my mental picture may be very different from yours.

Your questions are more related to sheet metal processing.
Look in the 'forming' chapter if the part is to be made in a press brake.
Look in the 'drawing' or 'spinning' chapter if the part is to be round.

You can easily find a data sheet from any of the producers of Inconel 625.

That will tell you that the yield point, which is important to forming, is roughly 4x that for mild steel. All that means is that the material fights back really, really hard, so you need stiff tooling.

Also, calculate the 'elongation' for your proposed bends and compare it with the given value for the material. As the elongation required to form your bend approaches the elongation at break, the chance of cracking the material while bending increases.




Mike Halloran
Pembroke Pines, FL, USA

 

[lukaszsz]

Is that half of a U-shaped straight part,

It is half of a U-shaped straight part

I'm totally green in Sheetmetal parts design, I got material properties for INCO 625 but no have idea if there are any guidelines / manufacturing requirements for walls slope and flange offset angle / radii. I know that springback is problem for walls (tahts whythere is a slope) and creeping/cracking is also a concern when radius is forming. The only I need is formulas / eng. tables to obtain proper values of those dimensions

Could You please post some links refers to publications that contains design guidelines for sheetmetal parts?

LukaszSz. Poland, Warsaw University of Technology, Faculty of Power and Aeronautical Engineering : MEchanical Engineering. BsC - 2013

 

[MikeHalloran]

http://www.amazon.com/Audels-Sheet-Metal-Workers-Handy/dp/B000J4JWM4

Mike Halloran
Pembroke Pines, FL, USA

 

[MintJulep]

Just by eyeball I wouldn't expect your part as-drawn to offer any particular difficulties to any half-way competent sheetmetal shop.

 

[berkshire]

Lucaszcz,
Inco 625 forms very much like stainless steel, if it is in the annealed condition. You should be able to achieve inside bends of 1.5 times the thickness of the metal in thicknesses of 1 to 5mm with no problem. The material will work harden, and you should try to get your forming done with as few press strokes as possible. on a 90* bend you should have about 3 to 4 * of spring back, however as this material work hardens very rapidly, spring back also increases.
B.E.

You are judged not by what you know, but by what you can do.

 

[Duwe6]

If possible, make these bends across the rolling direction. Everything has a propensity to try to split when tightly bent [and 1.5 T is tight] along the rolling [grain] direction.

 

[tbuelna]

625 Inconel sheet will be slightly more difficult to form than austenitic cres alloys. It has the same tendency to work harden during forming operations. Based on the ratio of panel thickness to bend radius shown in the sketch, there should not be a problem. But the overall shape of the part, including the relative location and orientation of the bends, might present some problems.

 

[lukaszsz]

Thank You all for those replies, i dig into some data and estimated springback for 90deg stamp walls to 3 deg and bend radii .060 for .032 sheet thickness. I;ve seen a lot of information (charts and tables) related to other cres alloys in martin marietta mechanical design book but in fact i was unable to find similar for INCO 625

LukaszSz. Poland, Warsaw University of Technology, Faculty of Power and Aeronautical Engineering : MEchanical Engineering. BsC - 2013

 

[tbuelna]

This document from Haynes Intl may be helpful:

http://www.haynesintl.com/pdf/h3159.pdf