INVESTIGADORES
FRONTINI patricia Maria
artículos
Título:
On the applicability of the load separation criterion to acrylonitrile/butadiene/styrene terpolymer resins
Autor/es:
C. BERNAL; A. CASSANELLI; P. M. FRONTINI
Revista:
POLYMER
Editorial:
ELSEVIER SCI LTD
Referencias:
Lugar: Amsterdam; Año: 1996 p. 4033 - 4039
ISSN:
0032-3861
Resumen:
Load separation constitutes the basis for the experimental evaluation of the J-integral by using the singlespecimentechnique. The objective of this present paper is to investigate the applicability of the loadseparation criterion for evaluating the ductile fracture mechanics parameters of acrylonitrile/butadiene/styrene (ABS) terpolymers. This criterion allows the load to be represented as the product of two separatefunctions, namely a material deformation function and a crack geometry function. Load separation impliesa method for J-integral evaluation by using only a single load-displacement measurement. The originalmethod for evaluating J used an energy-rate interpretation, which required several load-displacementmeasurements to be made for identical specimens with varying crack lengths. J methodology based on loadseparation introduces new parameters, i.e. ~7, Tel and ~pl, which greatly simplify the calculation of J andconstitute the basis for the J-R multiple specimen technique. Recently, a method for both theexperimental determination of the r/-factors and the verification of load separation, which is based onseparation constants, has been proposed for the testing of steel. This method allows the calibration of theq-factors in new test specimen geometries. This present paper attempts to evaluate experimentallywhether the principle of load separation is valid when testing ABS polymers in a bending configuration inorder to obtain a valid single J-testing method, and to calculate the r/plastic factor experimentally byusing this new simple method based on the load separation criterion in non-growing-crackmeasurements. In addition, a new approach based on the load separation principle which allows notonly the calculation of J from a single specimen, but also the calculation of J-R curves from one testmeasurement has recently appeared. This approach is called the 'normalization method' and has alreadybeen applied to the J-testing of two rubber-toughened nylons and one ABS polymer. However, loadseparation has only demonstrated for different specimen geometries in steels. In addition, the loadseparation in ABS terpolymers has been verified in this present paper for growing cracks, by using anexperimental procedure available in the literature.