ANALYSIS OF THE INFLUENCE OF TEST TEMPERATURE AND SPECIMEN SIZE IN THE DETERMINATION OF THE MASTER CURVE
Carlos Berejnoi1; Alvaro I. Ruiz1; Juan E. Perez Ipiña2
1 Facultad de Ingeniería, Universidad Nacional de Salta / CIUNSa; 2 CONICET / Facultad de Ingeniería, Universidad Nacional del Comahue
doi:10.20906/CPS/COB-2015-2247
Resumo
This work presents an analysis of the effects of specimen size and test temperature in the determination of T0, the reference temperature of the Master Curve for ferritic steels in the ductile-to-brittle transition region. The Master Curve procedure, for the determination of KJc(med) as a function of temperature, assumes a Weibull distribution with Kmin=20 MPa.m0.5 and slope b=4 for 1T specimen size. It is allowed the use of different specimen sizes, but it is mandatory the conversion of KJc data to equivalent KJc(1T). ASTM E 1921-14 presents the methodology for the calculation of T0, using datasets obtained at single and multiple temperatures. The standard imposes that the test temperature of dataset used for T0 calculation must be in the range T0 +/- 50 ºC. Single and multi-temperature options were applied to the Euro Dataset. For the first case, it is observed that the upper restrictive limit of temperature may be relaxed, using data censored if corresponds. When multi-temperature option is used, it is observed that the KJc(med) rises as specimen size increases, being the most conservative the KJc(med) obtained using 1/2T data. In these cases, it results more important the effect of specimen size than the effect of the test temperature used for the calculation of T0.
Palavras-chave: Ductile-to-brittle transition; Scatter; Master Curve