MartinaC 2 Report post Posted March 12 Hi everyone, I am modeling an additive manufacturing steel element and I have to define non-isotropic material (so an-isotropic or orthotopic), then I have to perform a non-linear analysis. Is it possible to add the non linear behavior to orthotropic or an-isotropic material? As for isotropic material MAT1 I can use MATS1 and TABLES1. Best regards Martina Quote Share this post Link to post Share on other sites
Rahul R 316 Report post Posted March 12 Yes it is possible to perform nonlinear analysis with orthotropic material. Till Optistruct 2017.1 we support small displacement analysis. Starting from OptiStruct 2017.2 we now support both small and large displacement analysis. PFA sample for deck for small and large displacement analysis. If possible use latest version 2018. composites_LGDISP.pdf frame_lgdisp_4.fem frame_SMdisp_4.fem Quote Share this post Link to post Share on other sites
MartinaC 2 Report post Posted March 12 Thank you! I'll try. Martina Quote Share this post Link to post Share on other sites
MartinaC 2 Report post Posted March 12 The parameters of the material MAT8 should be set on the linear elastic behavior. Then the behavior after yielding is defined in the MATX43. Is it correct? Quote Share this post Link to post Share on other sites
Rahul R 316 Report post Posted March 15 Please make sure to refer comments of MATX43. MATX43.pdf Quote Share this post Link to post Share on other sites
MartinaC 2 Report post Posted March 16 Perfect, I found them in Help>HyperWorks Desktop. Than you for the answers. Rahul R likes this Quote Share this post Link to post Share on other sites
MartinaC 2 Report post Posted March 18 Hi Rahul, what about PSOLID element? MAT8 is avaiable only for bi-dimensional element. Quote Share this post Link to post Share on other sites
Rahul R 316 Report post Posted March 18 Please check below post for MAT9ORT with PCOMPLS. MartinaC likes this Quote Share this post Link to post Share on other sites
MartinaC 2 Report post Posted March 20 Dear Rahul, Thank you for the link! I have CTETRA elements in my model, so I think I have to use MAT9ORT associated to PSOLID property. I do not have properties of each layer because my material has not proper layers. I have mechanical properties about the whole body obtained throughout tensile tests. My doubt is if the directions 1, 2 and 3 along which I have to define mechanical properties in MAT9ORT (as elastic modulus, Poisson's ratio etc.) are about local reference system of each element, or are about the global reference system xyz. And I do not understand how can I check direction 1, 2 and 3 in my model. Bests Martina Sigfrid likes this Quote Share this post Link to post Share on other sites
MartinaC 2 Report post Posted April 3 Hi, I model my sample using MAT9ORT Card Image for PSOLID elements. I activate the options for non-linear analysis MATX28 and select the TABLES1 for each direction, describing the non-linear behaviour. Results do not show the non-linear behaviour and maximum stresses exceed ultimate strength. I used the same procedure and tables I used for MAT1 (that works), but I do not have reasonable results. Please help me fixing my problem. I upload my model. If other files are needed I can upload them. Best regards Martina Sample_orth_NLQS.fem Sample_orth_NLQS_RESULTS.mvw Quote Share this post Link to post Share on other sites