Machine precision error
Machine precision error
(OP)
Hello,
I am trying to do tensile test using abaqus implicit analysis with time period 2. I need time increment less than 2 e-16 but abaqus keep on saying MACHINE PRECISION REQUIRES A TIME STEP GREATER THAN 2.22000E-16 how can I overcome this problem . Can anyone help? I even seen that when I delete the plastic strain values it works fine but when I enter it , it shows this error.
My yield stress Plastic strain
350 0
775 0.5
1200 1
I could not find palstic strain values in internet so just took this from example
I am trying to do tensile test using abaqus implicit analysis with time period 2. I need time increment less than 2 e-16 but abaqus keep on saying MACHINE PRECISION REQUIRES A TIME STEP GREATER THAN 2.22000E-16 how can I overcome this problem . Can anyone help? I even seen that when I delete the plastic strain values it works fine but when I enter it , it shows this error.
My yield stress Plastic strain
350 0
775 0.5
1200 1
I could not find palstic strain values in internet so just took this from example





RE: Machine precision error
RE: Machine precision error
RE: Machine precision error
Maybe post more details of your analysis?
RE: Machine precision error
I have attached the image for detail. my aim is to break the aluminium by tensile force where I put the lastic values in image too
RE: Machine precision error
RE: Machine precision error
(2) Double check your material constants.
(3) You have zero pivot warnings which suggest your model may not be adequately constrained.
(4) Your strain increment is so large at certain stages in the analysis that the solver has not attempted plasticity calculations.
I would review your material properties, boundary conditions and solution controls.
RE: Machine precision error
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RE: Machine precision error
RE: Machine precision error
RE: Machine precision error
Abaqus Example Problems Guide
Section 2.1.16 "Progressive failure analysis of thin-wall aluminium extrusion under quasi-static and dynamic loads"
As suggested above, get some help/supervision if you can. When a static analysis fails to converge, the solver will often suggest that the increment required is lower than the minimum specified. In most cases, this is indicative of problems elsewhere and simply dropping the increment size will not improve convergence.
RE: Machine precision error
I learned how to make it. Now the model works. Thanks for the help. Am still a student trying to learn abaqus for my research on my own, where my supervisor knows that and this website taught me a lot.
RE: Machine precision error
b) One comes across way too many folks (in these forums) trying to swim across Nile when they barely know how to swim.
c) You should begin with the Getting Started Guide (Interactive) and Abaqus/CAE User's Guide. Take your time (two weeks or more, if that is what it takes). Learn the basics of linear analyses with linear elastic materials, small strains/rotations, and no contact - in a static analysis.
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