rndetermination of rock mass deformation modulus is very important in different projects, especially in civil and mining engineering works. in-situ measurements such as dilatometer, plate load and flat jack methods may be applied to determine the deformation modulus. however, these methods are very expensive and time- consuming. analytical methods are very useful approaches which can also be us...

superplastic materials show a very high ductility. this is due to both peculiar process conditions and material intrinsic characteristics. however, a number of superplastic materials are subjected to cavitation during superplastic deformation. evidently, extensive cavitation imposes significant limitations on their commercial application. the deformation and failure of superplastic sheet metals...

this study was conducted in order to investigate the influence of plastic deformation on the transformation of retained austenite in a trip steel with a high content of al and a low content of si. to the aim, appropriate treatments were used to produce the starting material (trip steel). the microstructure of the obtained steel was composed of bainite and phases including ferrite and retained a...

The design of extrusion dies depends on the experience of the designer. After the die has been manufactured, it is tested during an extrusion trial and machined several times until it works properly. The die is designed by a trial and error method which is an expensive process in terms of time and the amount of scrap. In order to decrease the time and the amount of scrap, research is going on t...

AIM To investigate the incidence of fracture and deformation observed on Reciproc instruments after clinical use. METHODOLOGY A total of 1696 Reciproc NiTi instruments that were discarded after normal clinical usage over 30 months were collected. Of these 1580 instruments were R25 (93%), 76 were R40 (5%), and 40 were R50 (2%). The treatments included 3780 root canal preparations, 3023 primary...

The quasi-static and dynamic compressive behavior of pyramidal truss cores made of 304 stainless steel were investigated using a combination of experimental techniques. Quasi-static tests were performed using a miniature loading stage while a Kolsky bar apparatus was used to investigate intermediate deformation rates. High deformation rates were examined using a light gas gun. Optical imaging o...

in this work, dynamic mechanical properties of three high-manganese steels with trip/twip or fully twip characteristics are studied. high strain rate experiments in the range of true strain rates between ~500 and 1800 /s are conducted using a dynamic torsional testing setup. all the three steels show a positive strain rate sensitivity in the intermediate range of strain rates (up to 500 /s). bu...

in this paper, the correlation between the surface rumpling and cracking phenomena with twinning mechanism during plastic deformation of hadfield steel has been investigated. the effect of stacking fault energy and the amount of strain are evaluated. the experimental samples with specific amounts of carbon, manganese and aluminum resulting in different stacking fault energies, were produced usi...

the flow stress of steel depends significantly on microstructural changes taken place during hot deformation processes. in hot deformation processes, the flow stress of steel is influenced by two main metallurgical phenomena, i.e. recovery and recrystallization, along with its chemical composition and thermo-mechanical parameters. the final mechanical properties of steel are also determined by ...