High strength steel K factor

Hello,

I am working with high strength steel grade S700MC and I would like to know if somebody here work with it and which parameters you use in SW for it. I think the K factor should be between 0.4 and 0.5 but difficult to have something accurate with our trial a 0.05 change a lot in fact.

Or press brake software use the same rule for unfold S355 and S700MC for me that is wrong but I need your help for find out.

Hope that make sense.

Thanks,

SolidworksSheet Metal