Fracture resistance of shell-steel reactor steel with mixed deformation modes for justification of extension of nuclear power plants lifetime
Journal Title: Праці Одеського політехнічного університету - Year 2017, Vol 1, Issue 51
Abstract
Preliminary thermomechanical loading promotes increase of resistance to brittle fracture of heat-resistant steels with fractures and is the fundamental basis of the perspective method of increasing the resource for ensuring safe operation of power reactor corps. In existing standards for calculating the strength of equipment of nuclear power plants, the calculation for fracture toughness is performed only for plane opening mode of fracture (mode I), but the plane of the fracture can have an arbitrary orientation with respect to external forces. Aim: The aim of the research is an experimental study of the effect of the preliminary thermomechanical load under modes I and II on the fracture toughness for modes II and I of reactor steels, respectively, as well as the preliminary thermomechanical load under the I + III mode for the fracture toughness under the I + III mode. Materials and Methods: Experimental studies of static fracture resistance were performed on samples on four-point bending (mode II), on cylindrical specimens torsion (mode III), and on a modified compact sample with an oblique fracture (mode I + III) for 15Ch2NMFA(II) and 15Ch2MFA(II) steels. Results: It is shown that the fracture toughness characteristics for transverse and longitudinal displacements (modes II, III) are smaller than for normal detachment (mode I) at a test temperature exceeding the brittle-viscous transition temperature, and vice versa, more when the test temperature is lower. It was found that the preliminary thermomechanical load under mode II causes an increase in the fracture toughness under mode II and a reduction in the fracture toughness under mode I for tempering embrittlement reactor steels. Under these conditions, this index practically does not change for plastic reactor steels. The established patterns show the need to modify regulatory documents to assess the ultimate bearing capacity of structural elements with fractures, in particular, the shells of nuclear power reactors, equipment of the 1st and 2nd circuits, pipelines.
Authors and Affiliations
V . V . Pokrovsky, V . G . Sydiachenko, V . M . Ezhov
Keywords
Related Articles
- EP ID EP311530
- DOI 10.15276/opu.1.51.2017.03
- Views 167
- Downloads 0
Numerical and experimental investigation of heating processes in rubbercord composite un-der cyclic deformation
Composite materials such as elastomers, are widely used in modern engineering. An essential feature of such mate-rials is their viscoelasticity. It’s accompanied with the release of energy as a heat. The self-heating pro...
The role of ecological safety in ergonomics development
The problem of a necessity of application of ecological safety aspects for increasing of ergonomics decisions effectiveness is considered. Actuality of the marked problem is conditioned by the presence of close intercomm...
Obtaining solutions of silver nanoparti-cles under plasma discharge
The paper considers obtaining water solutions of silver nanoparticles with contact non-equilibrium low tem-perature plasma discharge. The aim of the work is to study the influence current of a discharge non-equilibrium l...
Optimal operational regimes of sea water desalination plants with mechanical vapor compres-sion
Desalination of sea water is becoming more urgent for many regions. In the coming decades water will be used for desalination from various reservoirs of the World Ocean. It is important to determine the operating modes o...
Plasma-chemical preparation of nanoscale cobalt oxide
As of today, sols and nanodispersed systems of transition metal oxides are increasingly spreading. Due to a number of properties, undoubted interest for the development of technologies in various industries is represente...