Ciclic Hardening Simulation 1

[engeserv03]

Hello,

I would like to develop a simulation to a carbon-steel pipe (A106B) which has a cyclic loading temperature ( 21oC to 300 oC to 21 oC )due this loading, restrictions and stiffiness are got internal stresses and in someplaces in this pipe (curves) the local level of these stresses are above yelding point.
My goal would be to verify if this level of stresses can decrease with pass of cycles ( after 10 for ex.) due to cyclic elasto-plastic effects.
Reading the Abaqus manual, I could verify the simulation resources to apply "isotropic or kinematic hardening to cyclic loadings " but I am having very difficults to get and apply correctly the "material parameters" or "option configuration" for this.

Someone would have similar experiences with Abaqus and could help me.

Thanks for all

 

[TGS4]

Where are you getting your cyclic stress-strain curve data from? We'd be glad to help you, but you need to ask very specific questions first.

 

[engeserv03]

HI TGS4,

As I said I would like to verify if the level stresses decrease after some temperatures cycles due to elastic-plastic effects.

The material is a carbon steel pipe ASTM A106B which has
tensile strenght= 42 kgf/mm2 , yeld strenght = 24,6 kgf/mm2 and the max. elongation = 26%

I tried to apply in Abaqus 6.5.1, the following properties sets:

Plastic>Hardening=Combined
Data Type=half cycle
Suboption: Cyclic hardening
Values
1)yield stress = 24,6 plastic strain = 0
2)yield stress = 42 plastic strain = 0,26

and the same values to "equiv stress" and equiv plstic strain"

With this inputs, I could get the residual stresses, the final stress ( = yield stress) but the stress values did not change after 10 cycles.

I think that the inputs values are not suitable for this kind of simulation.
If I to work with, Hardening > Combined
Data Type > Parameters

I need to inform: "yeld stress at zero plastic strain" and
"kinematic hard parameter C "

I am not sure about these values. Could you give me some orientation ?

Thanks