![](\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/08\/08-08-2023-1691501573-mceclip0.png\")
<\/p>\nI am trying to simulate part of a system which works under high pressure (1GPa). I am using a 2D axisymmetric model for that:<\/p>\n
<\/p>\n
I’ve fixed the model in one edge that should represent the threaded connection to an external fixture device and applied pressure on the edges up until where the sealing (not represented) should act. Axis of symmetry is on the bottom edge of the smaller part. Contact between the parts is frictionless.<\/p>\n
Both parts are from stainless steel (DIN 1.4542) hardened to H1050 condition (yield strength = 1140 MPa and Tensile Strength 1210 MPa). As the manufacturer could not provide me a strain stress curve, I am using a bilinear hardening model, with a tangent modulus of 512 MPa (extracted arbitrarily from literature).<\/p>\n
The problem is that the simulation converges very well until the very last iteration, where suddenly some elements become highly distorted (usually near the contact regions with radii). I tried tweaking the settings with everything I could: intense mesh refinement, improved contact settings, several substeps, etc. I don’t know anymore how I could fix that. My idea is that it this behavior is probably related to the material model, but I can’t explain exactly why this would happen.<\/p>\n