✍ Scribed by D Franşois; A Krasowsky
No coin nor oath required. For personal study only.
A plane strain transition temperature for a given specimen thickness is defined for ferritic steels as the temperature along the K,c transition curve where the ASTM validity limit is reached. It corresponds to a ratio p of the thickness to (K&T,)* proportional to the plastic zone size, equal to 2.5. An empirical formula describing the K,c transition curve yields a relation between the plane strain transition temperature, yield point and the thickness, which depends upon the chosen value of p. For a given steel transition temperatures deduced from other tests such as the temperature corresponding to the initiation of stable tearing, the Charpy FATT, the NDT, the DWTT-FATT, were found to correspond to various characteristic values of the p ratio. This was checked using results found in the literature for different steels. This relation between a particular transition temperature and the thickness, which depends upon the shape of the K,c transition curve, the yield stress and the corresponding value of the p ratio, is useful to make predictions about the thickness and the strain rate effects. It can be used to deduce transition temperatures of various tests from the knowledge of either the K,c transition curve or from two other transition temperatures. It could provide a method to decide when the stress relief is needed after welding plates of a given thickness. It should also find its use in studying irradiation effects.
📜 SIMILAR VOLUMES
The paper focuses on the behaviour of materials for which the onset of crack extension and unstable fracture coincide in a rising load fracture mechanics test. A theoretical analysis shows that use of the experimental test JIG value gives a non-conservative prediction of unstable fracture when a str
The fracture toughness of the tempered martensitic stainless steel Eurofer97 has been experimentally characterized in the ductile-to-brittle transition (DBT) region with sub-sized compact tension specimens. The median fracture toughnesstemperature curve in the lower transition region has been found