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ASTM E399, 1999 – Standard Test Method for Plane-Strain Fracture Toughness of Metallic Materials. 106 APÊNDICE Tabela 1 – Valores da correção de curvatura da trinca de fadiga * Corpo-de-prova com sobrecarga REGIÃO R CORPO-DE-PROVA K máx final K máx correção DIFERENÇA (%) cp 1 58,60 65,93 12,5 cp 2* 66,21 70,24 6,0 cp 3 64,10 64,14 0,1 cp 4 54,47 58,10 6,6 0,1 cp 5 64,10 68,37 6,6 cp 1* 93,42 98,48 5,4 cp 2* 93,42 101,55 8,7 cp 3 82,13 87,89 7,0 METAL DE BASE 0,5 cp 4 95,19 95,24 0,05 cp 1 58,60 62,13 6,0 cp 2* 70,82 75,77 7,0 cp 3 66,18 70,03 5,8 0,1 cp 4 73,13 77,01 5,3 cp 1* 93,42 102,64 9,8 cp 2* 93,42 100,59 7,6 cp 3 91,27 96,90 6,1 METAL DE SOLDA 0,5 cp 4 93,42 98,95 5,9 cp 1 56,76 64,50 13,6 cp 2* 64,10 70,87 10,5 0,1 cp 3 72,87 76,68 5,2 cp 1 80,63 93,41 15,8 cp 2 97,28 101,79 4,6 ZTA 0,5 cp 3* 93,42 106,44 13,9