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Introdução ao comportamento mecânico dos materiais ��������� ��� ���������� �����ff��fiffifl �! � �"�#�%$&� '��(�)� �+*ffi,-,-* 1 Introdução .0/&13254�2568792:732<;(79=�>5=@?A/�BC25?D25687�EF=@4�79GH/�IC>5=H4�J�254�>513IK79=H4L6�E E@/M=@4�79ICBNEPORQR687913=(J�S�T5U@=�E@= >V=H?A/W=H1X7�EZY ?D256879=[?A2V>]\@6&I^>5=@4�J�=H4_?`EZ79251�INE@IC4XacbKd<ef2-gffiJ�2VJ�I^>5E@JhEPE@=[>5S�1�43=�i#jlk[mndpoHocYMQR687913=(J�S�T5U@=�qP>VI^rV6�>5I^E J�=H4-?`EZ79251�INE@IC4ffi/hE@19EsEt256&uH256�v�E@13I^EZaxw&J�2�132V43/W=H6�49Ezy�I^BCI^JhE@J&2�J�=|{%25/hEz1�7�Ez?A2V6f73=|J�2%}ffi6&uH256�v�E@13I^E jl2<7�E@BC~�13uHIC>]ED2|J�2jlEz792V13INEzI^4[JhE}L43>5=@BNEi!=HB^IK79g5>V6�I^>5EDJ�E�6�IKH251�43ICJhE@J�2sJ�2 &U@=i�E@S�BC=�%132<Y /�1�=nJ�S&T]U@=sJ�254X792%J&=n>VS�?A2V6879=t6�Es^687325uH13Ex=HSA25?Ł/hE@1X792V4g[/M2V13?DIC79ICJhE /hE@13Ex=Hyf�2V79IKH=H4-J�I^J�z79IC>5=H4 432V?h6�4P>5=@?A2V13>5I^E@I^42xJ&2543J&2sfS�2xE=H68792 432R3ED>VIC79E@JhE& E/�1�I^?D25I^13E`/hE@1X792 J�2V4�7�EE@/W=H4�73I^B^EA=H19Ez?7913Ez7�EzJ�=H4�=H4xE@43/W25><79=H4�uH2V19E@IC4 JhE13254�/M=@4�7�EJ�2 S�? 43G@B^I^J&=|J�2V=@13?Ap@25B_E|S�?254X=H13TV=A?D25>5\@6�I^>V=|2<;(7325136&=�{�I^43>VS&79IC19E@?YR4�2FE@4:1�254�/M=H4X7�E@4P6�= 1�25uHIC?A2 25B^@4�73I^>V=[2ffi6�=�132VuHI^?D2�/�B^@4�73I^>5=&wZyW25?">V=H?D=�EzB^uHS�?AE@4>5E@19Ez>V792V13C4�79IC>]E@4_2V43/W25>5I^E@I^4_J�2#>52V1�79E@4>VBNE@4�432V4 J�2�?AEz792V13INEzI^45 ./&13254�2568792792;n73=B^I^J�ES�6�JhE@?D256879E@B^?D2568792>V=H? =2<25IC73=JhE�7925?D/W2519EZ79S�13E2J�E79EZ;&EJ&2 J�2<=H13?AE@T]Uz=0 ¡F¢¤£¦¥ £R§ 43=@y�132=>V=H?D/M=H1X7�E@?D256873=?A2V>]\@6&I^>5=`J�=H4 ?AEz792V13INEzI^45F}ffi?E@J�ICT]U@=`432|¨E@13 S�?AEFy�132<H2:J�IC43>VS�4343U@=�43=Hy�1�2:=F256�©@?A2V6�= JhE%¨E@J�ICu8E%?D25>5\@6�I^>5E&wH2V?+4�25S�4#E@4�/M2V>V79=@4L?`E@IC4�uH2V19E@IC45 1.1 Temperatura ª taxa de deformação .E@S&?A2V6f73=`JhE792V?A/W2513Ez79S&19E J�2sS&?�43I^4X792V?`E >5=H1�132V43/W=H6�J�2sEAS�?�EzS�?A2V6879=DJhED2V6�251�uHINE >5IC6�g<Y 79IC>]E J�=H4�z79=@?A=H4:2]«z=HSl?A=HBCg5>VS�BNE@4:fS�2x>5=@?A/W¬n2V?254X792s43I^4X792V?`E&-QR4�73=`/W=nJ�2�4�251%J&25?D=H6�4�7319E@J&= 25?S�?`E�@1�2]E JhEF^4�I^>5EF>5=H6�v&25>5ICJhE >5=H?D=%O�jl2V>]\@6&I^>]E�}L4�79Ez79C4�73I^>]Ea�i=H1ffi?D25I^= J�E@4L251313E@?D25687�E@4 J�2V4�7�EJ�IC43>VI^/�BCI^6hE /M=(J�2YR432V1FJ�2V?A=H6&4�7913E@1FfS�2 E`?Dg5J&INE`JhE2V6�251�uHINEA>5I^6&gV79IC>]E`J&=H4�z79=@?A=H4[2p«Z=HS ?D=HB^gV>5S�B^E@4 J�=®4�I^4X7925?AEg`¯%°xw�=@6�J�2A¯)g`E>5=@6�4�79E@68792`S&6�IC@251343E@B#J�=H4xu8E@432V4t2 °Łg`E792V?A/W2<Y 19EZ79S�13EE@y�43=@B^S&79E&�}L?¤S�?±43GHBCI^J�=A25?1325/W=HS�4�=E`256�2V13uHI^E>5IC6�gV73I^>]EAJ�=H4 z73=H?D=H4%2V4�7�>V=H6879I^J�E 6�=?A=p(I^?D256873=nICy�19EZ79GH1�I^=�w6&=?D=p(I^?D256879=J�2D13=z7�E@>5U@=JhE@4�?D=HB^gV>5S�B^E@4F2 6�=?A=p(I^?D256879=J&2 7913E@6�4�BNE@T5U@=�w�fShE@6�J&==(>5=@13132J&ICS�43U@=�{%2V4�79E=H1�?`E`=IC6�>51�25?D2V79=JhE7325?D/M2V19Ez73S�19E¨E@>VI^B^IK7�EAE =(>5=H1�13r56&>5INEJ�=@4[/&13=(>5254�43=H4[J�2�J�2<=H13?AE@T]Uz=/�BN@4X79IC>]E|6�=D?`EZ79251�INE@B² i=(J�2V?A=H4PJ�2<h6�IC1PE@uH=H13EDE|79EZ;&E J&2xJ&2V=H1�?`E@T5U@= >5=H?D=�³ ¡-¢)´ ¡ ´Hµ ¶ d@Cd· .F6�J�2 ¡ g%E J�2<=H13?AE@T]Uz=x2V43/W25>VCh>5Ex6�=@13?AE@B¸�¹=H?D= ¡ gPS�?º6f~�?D251�=tE@J&I^?D256�4�I^=H6hEzB¸wHE�~�6�ICJhE@J�2 JhEs79EZ;&EtJ�2FJ&2V=H1�?`E@T5U@=t4�2513»½¼z¾h¿RÀ²LQR6879S�IK79ICzE@?D2568732�43E@yM2V?A=@4fS�2F=H4/�13=(>52V4343=@4cJ�2FJ�2<=H13?AEZY T]Uz=x/&BN@4X79I^>5E%6hU@= =(>5=@13132V?IC6�4�79E@687�E@6�25E@?D2568792zw86�25>V25434�IC79E@6�J�=xJ�2:S�?+I^68792V1�zE@B^=%J�2c792V?A/W= /hE@13E m σ ε T dε/dt Á ICuHS�19Ed@CdH³�}�;n2V?A/�BC=`J�=@4%2V2VIC73=H4%JhED7925?D/W2519EZ79S�13EA2tJ�ED7�E;�EAJ�2tJ�2<=H13?AE@T5U@=`4�=Hy�132s=>5=@? 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