{"id":457974,"date":"2026-05-11T21:06:24","date_gmt":"2026-05-11T21:06:24","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/mat_063\/"},"modified":"2026-05-11T21:06:24","modified_gmt":"2026-05-11T21:06:24","slug":"mat_063","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/mat_063\/","title":{"rendered":"MAT_063"},"content":{"rendered":"<p>&lt;p&gt;Hello,&lt;\/p&gt;&lt;p data-pm-slice=&#8221;1 1 []&#8221;&gt;I want to run a simulation using MAT_063 (Crushable Foam), with Model 1 selected in the material card. I have read the documentation for this material model, and as far as I understand, the material requires the yield stress as a function of volumetric strain.&nbsp;My first question is whether I should provide only the plastic part of the stress&ndash;strain curve obtained from experiments, or if the material requires the entire stress&ndash;strain curve. Also, is it possible to use stress&ndash;strain data obtained from a uniaxial compression test?&lt;\/p&gt;&lt;p data-pm-slice=&#8221;1 1 []&#8221;&gt;The other question concerns a warning I receive in Keyword Manager &rarr; Model Check &rarr; Keyword Check for the defined material (MAT_63). The warning message states:&nbsp;&#8220;MAT_CRUSHABLE_FOAM (ID: 1): curve 1 does not monotonically increase.&#8221;&nbsp;The experimental stress&ndash;strain curve contains drops in stress, as shown in the figure below as an example. What should I do in this case to be able to use this material model and resolve the warning?&lt;\/p&gt;&lt;p data-pm-slice=&#8221;1 1 []&#8221;&gt;Does anyone have any ideas about these questions?&lt;\/p&gt;&lt;p&gt;&lt;span style=&#8221;font-size: 14pt;&#8221;&gt;<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2026\/05\/11-05-2026-1778533034-mceclip0.png\" width=\"326\" height=\"252\" \/>&lt;\/span&gt;&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-457974","topic","type-topic","status-publish","hentry","topic-tag-foam-1","topic-tag-lsdyna","topic-tag-stress-strain-curve"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_forum_id":["27814"],"_bbp_topic_id":["457974"],"_bbp_author_ip":["142.104.85.82"],"_bbp_last_reply_id":["0"],"_bbp_last_active_id":["457974"],"_bbp_last_active_time":["2026-05-11 21:06:24"],"_bbp_reply_count":["0"],"_bbp_reply_count_hidden":["0"],"_bbp_voice_count":["1"],"_bbp_engagement":["682300"],"_btv_view_count":["74"],"_bbp_topic_status":["unanswered"]},"test":"lsdyna928gmail-com"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/457974","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics"}],"about":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/types\/topic"}],"version-history":[{"count":0,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/457974\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=457974"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}