Flamanville EPR RPV’s Heads Carbon Segregation: Tests Program Definition to Characterize the Mechanical Properties of the Carbon Segregation

2018 ◽  
Author(s):  
Stéphane Marie ◽  
Jérôme Demarecaux ◽  
Philippe Fichot ◽  
Elisabeth Keim ◽  
Johannes May ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Carbon Content ◽  
Mechanical Tests ◽  
Main Issue ◽  
Residual Carbon ◽  
Testing Program ◽  
Carbon Segregation ◽  
Brittle To Ductile Transition ◽  
Drop Weight ◽  
The Impact

To characterize the mechanical properties of the residual carbon segregation of the Flamanville EPR RPV heads, a testing program have been organized by Framatome and performed in 3 laboratories (Wood, Framatome technical center of Erlangen and SCK Mol). This paper presents the tests program, how it has been defined and its goals. The main issue was the impact of the carbon content on the toughness properties. A procedure was defined to characterize specifically the toughness distribution in the upper part of the brittle-to-ductile transition. The ductile regime was also investigated. These tests were completed with tensile, Charpy and drop weight tests, representing a final total of approximatively 1700 mechanical tests.

Flamanville EPR RPV’s Heads Carbon Segregation: Characterization of the Segregation in the Heads

2018 ◽  
Author(s):  
Philippe Fichot ◽  
Olivier Calonne ◽  
Mathieu Segond ◽  
Stéphane Marie ◽  
Yvon Desnoyers ◽  
...  
Keyword(s):  
Carbon Content ◽  
Residual Carbon ◽  
Testing Program ◽  
Specific Strategy ◽  
Carbon Segregation ◽  
Geostatistical Approach ◽  
Short Time ◽  
Non Destructive

To characterize the mechanical properties of the residual carbon segregation of the Flamanville EPR RPV heads, a testing program has been defined by Framatome using three sacrificial representative heads. The first step of this program was a 3D characterization of the carbon content inside each piece. A specific strategy has been defined using two methods for the carbon measuring: - In situ measurements using a mobile arc spark spectrometer. This device allows a higher number of non-destructive measurements in a particularly constrained environment and in a short time, - Conventional spectrometry performed on chips sampled from the pieces. This technique is more accurate but is destructive and more time consuming. Also, to consolidate the representativeness of the sacrificial vessels heads, the results were analysed using a geostatistical approach. This paper presents how these two techniques have been used to characterize the carbon content in the segregated part of the pieces and the conclusion of the geostatistical analyses.

Flamanville EPR RPV’s Heads Carbon Segregation: Impact of the High Carbon Segregation on the Mechanical Properties of the RPV Steel

2018 ◽  
Author(s):  
Stéphane Marie ◽  
Jérôme Demarecaux ◽  
Philippe Fichot ◽  
Mejido Hajjaj ◽  
Cecile Miller
Keyword(s):  
Mechanical Properties ◽  
Carbon Content ◽  
Worst Case ◽  
Carbon Segregation ◽  
Brittle To Ductile Transition ◽  
Rpv Steel ◽  
Extensive Test ◽  
Higher Temperature ◽  
Integrity Assessments ◽  
Acceptance Tests

To characterize the mechanical properties of the residual carbon segregation of the Flamanville EPR RPV heads, a testing program have been organized by Framatome and performed in 3 laboratories. Three sacrificial pieces have been used for this program, allowing the investigation of different carbon contents, coupled with different quenching conditions (thanks to a specimen sampling at different positions in the heads thickness). As expected, the increase of the carbon content leads to an increase of the tensile properties, a shift toward the higher temperature of the brittle-to-ductile transition and a lowering of the toughness in the ductile regime. In the worst case, compare to the RTNDT measured in the frame of acceptance tests of the heads, the temperature to be considered to envelop all the experimental results with the toughness curve of the RCC-M code is 20°C higher. The extensive test program allows a quantification of these impacts for the integrity assessments of the RPV. It is also demonstrated that the segregated material remains homogeneous, with a classical failure mode by cleavage. Master Curve approach is also applicable and used to characterize the carbon content impact on the toughness properties.

Research on the Flow Characteristics of Polymer Injection Molding under Ultrasonic Vibration and Plastics’ Mechanical Strength

2010 ◽  
Vol 37-38 ◽  
pp. 1092-1100
Author(s):  
Ji Bin Li ◽  
Ke Ke Xu ◽  
Xin Bo Lin ◽  
Xiao Yu Wu ◽  
Guo Li Gao
Keyword(s):  
Mechanical Properties ◽  
Injection Molding ◽  
Ultrasonic Vibration ◽  
Flow Characteristics ◽  
Mechanical Tests ◽  
Impact Testing ◽  
Melt Flow Rate ◽  
Polymer Injection ◽  
Molding Method ◽  
The Impact

In this paper, ultrasonic vibration is adopted and exerted on injection molding in order to improve plastics’ forming ability, and the impact testing is used to analyze different injection parts’ mechanical properties. On the one hand, experiments prove that ultrasonic vibration can increase polymer’s melt flow rate, decrease melt viscosity, and improve injection flowing in mould cavity. On the other hand, the mechanical tests prove that the ultrasonic vibration can improve plastics’ tensile strength, elastic modulus and other mechanical properties. As a result, a weldless ultrasound-assisted injection molding method is recommended.

Towards improved understanding of PEG-impregnated waterlogged archaeological wood: A model study on recent oak

Holzforschung ◽  
2010 ◽  
Vol 64 (2) ◽  
Author(s):  
Ingela Bjurhager ◽  
Jonas Ljungdahl ◽  
Lennart Wallström ◽  
E. Kristofer Gamstedt ◽  
Lars A. Berglund
Keyword(s):  
Mechanical Properties ◽  
Microfibril Angle ◽  
Mechanical Tests ◽  
Chemical Degradation ◽  
Cellulose Microfibrils ◽  
Radial Compression ◽  
Biological Degradation ◽  
Archaeological Wood ◽  
Waterlogged Archaeological Wood ◽  
The Impact

Abstract To prevent deformation and cracking of waterlogged archaeological wood, polyethylene glycol (PEG) as a bulk impregnation agent is commonly applied. PEG maintains the wood in a swollen state during drying. However, swelling of wood can reduce its mechanical properties. In this study, the cellular structure of oak and cell wall swelling was characterized by scanning electron microscopy (SEM) of transverse cross-sections, and the microfibril angle of oak fibers was determined by wide angle X-ray scattering (WAXS). Samples of recent European oak (Quercus robur L) impregnated with PEG (molecular weight of 600) were tested in axial tension and radial compression. Mechanical tests showed that axial tensile modulus and strength were only slightly affected by PEG, whereas radial compressive modulus and yield strength were reduced by up to 50%. This behavior can be explained by the microstructure and deformation mechanisms of the material. Microfibril angles in tensile test samples were close to zero. This implies tensile loading of cellulose microfibrils within the fiber cell walls without almost any shear in the adjacent amorphous matrix. These results are important because they can help separate the impact of PEG on mechanical properties from that of chemical degradation in archaeological artifacts, which display only small to moderate biological degradation.

scholarly journals Some Mechanical Properties of Experimental Mg-Al -RE-Mn Magnesium Alloys

2014 ◽  
Vol 14 (1) ◽  
pp. 13-16 ◽  
Author(s):  
K.N. Braszczyńska-Malik
Keyword(s):  
Mechanical Properties ◽  
Rare Earth ◽  
Impact Strength ◽  
Rare Earth Elements ◽  
Mass Fraction ◽  
Brinell Hardness ◽  
Mechanical Tests ◽  
Gravity Casting ◽  
Compression Properties ◽  
The Impact

Abstract The results of some mechanical properties of four Mg-5Al-xRE-0.4Mn (x = 1 - 5) alloys are presented. The microstructure of experimental alloys consisted of an α-Mg phase and an α+γ semi-divorced eutectic, Al11RE3 phase and an Al10RE2Mn7 intermetallic compound. For gravity casting in metal mould alloys, Brinell hardness, impact strength, tensile and compression properties at ambient temperature were determined. The performed mechanical tests allowed the author to determine the proportional influence of the mass fraction of rare earth elements in the alloys on their tensile strength, yield strength, compression strength and Brinell hardness. The impact strength of the alloys slightly decreases with a rise in the rare earth elements mass fraction.

scholarly journals Reinforcing polypropylene with calcium carbonate of different morphologies and polymorphs

2018 ◽  
Vol 25 (4) ◽  
pp. 745-751 ◽  
Author(s):  
Yanwei Jing ◽  
Xueying Nai ◽  
Li Dang ◽  
Donghai Zhu ◽  
Yabin Wang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Calcium Carbonate ◽  
Mechanical Tests ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Crystallization Property ◽  
Reinforced Composite ◽  
Treated Sample ◽  
The Impact

Abstract The influence of calcium carbonate (CaCO3) with different polymorphs (calcite and aragonite) and morphologies (granular and rod-like) on mechanical and crystallization properties of polypropylene (PP) was investigated. Meanwhile, these CaCO3 fillers coated with oleic acid were added in different contents to PP. The results indicate that the tensile strength, flexural strength, modulus, and crystallization property of the filler-treated samples are improved, but the impact strength decreased. The crystallinity of the composites is higher than that of neat PP. Moreover, in the rod shape filler-treated sample, in both whisker species, the mechanical properties of composites are superior to the particles filled. Differential scanning calorimetry, X-ray diffraction, and mechanical tests display that calcite whisker-reinforced composite has higher crystallization enthalpy, melting enthalpy, degree of crystallinity, and mechanical properties than aragonite whiskers and calcite particles filled composites.

Influence of Carbon Content in Cobalt-Based Superalloys on Mechanical and Wear Properties

2004 ◽  
Vol 126 (2) ◽  
pp. 204-212 ◽  
Author(s):  
Rong Liu ◽  
Matthew X. Yao ◽  
Xijia Wu
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Carbon Content ◽  
X Ray Diffraction ◽  
Wear Properties ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Pin On Disc ◽  
Rotating Bending ◽  
The Impact

Two cobalt-based superalloys containing 1.6% and 2% carbon respectively were studied, with the emphasis on the influence of the carbon content on their microstructures, wear resistance, and mechanical properties. Phase formation and transformation in the microstructures were analyzed using metallographic, X-ray diffraction, and differential scanning calorimetry techniques. Wear resistance, tensile and fatigue behaviors of the alloys were investigated on a pin-on-disc tribometer, MTS machine and rotating-bending machine, respectively. It is found that the wear resistance was increased significantly with the carbon content. The mechanical properties of the alloys are also influenced by the carbon content, but the impact is not so significant as on the wear resistance. It was observed that the carbon content increased the yielding strength and fatigue strength, but decreased the fracture stress and fracture strain.

Analysis of the Mechanical Properties of Pristine and Thermally Aged PC/PMMA Micro and Nanolayered Films

2010 ◽  
Author(s):  
Hui Shen ◽  
N. D. Gannon
Keyword(s):  
Mechanical Properties ◽  
Film Thickness ◽  
Polymer Films ◽  
Thermal Aging ◽  
Layered Structures ◽  
Mechanical Tests ◽  
Hierarchical Systems ◽  
Process Technology ◽  
Barrier Materials ◽  
The Impact

Microlayered polymer films are synthetic polymers with biomimicking layered structures which have been successfully commercialized. Nanolayered polymer films have been developed in recent years using advanced process technology. The innovative nanolayered polymer films have more complex hierarchical systems with truly biomimic nature. There are many potential applications for the nanolayered films such as gas barrier materials and spherical gradient refractive index lens. However, as polymers possess many properties that are different from metals and other traditional materials, the mechanical properties of the polymer films can vary widely depending on the material formulation, environmental temperature, and time. In this work, standard mechanical tests have been conducted to study the relationship between the mechanical properties and the layered structures. The impact of thermal aging on the mechanical behavior of the micro and nanolayered polymer films has also been investigated experimentally. The composition of the polymer films under study are 50vol% polycarbonate (PC) and 50vol% poly(methyl methacrylate) (PMMA). The layer thickness ranges from 31 nm to 32 μm and the film thickness 50.8 μm to 254 μm. These films were thermally aged at 115°C and 125°C in a constant temperature oven for up to four weeks. The mechanical properties, including the modulus of elasticity, tensile strength and ductility, have been tested on the pristine and thermally aged films. It has been observed that the mechanical properties of the films vary with the layered structure and film thickness. The thermal aging temperature and aging time have significant effects on the overall character of the stress-strain responses. Films with different thicknesses and layer formations respond to the thermal conditions differently.

Flamanville EPR RPV’s Heads Carbon Segregation: Vessel Heads Manufacturing

2018 ◽  
Author(s):  
Benoit Lefever ◽  
Stéphane Marie ◽  
Thierry Berger ◽  
Isabelle Bobin Vastra
Keyword(s):  
Carbon Content ◽  
High Carbon ◽  
High Carbon Content ◽  
Testing Program ◽  
Carbon Segregation

The FA3 RPV heads segregation has been an important issue for the Flamanville 3 EPR project. A high carbon content of carbon has been measured at the outer central part of the two heads. Manufactured in 2006 according to the RCC-M requirements, these pieces were also submitted to the ESPN (i.e. nuclear pressurized equipment) French order requirements, and in particular the ESPN technical qualification. This paper presents the manufacturing of these heads to explain the origin of the segregation and place this process in its context, with in particular a clarification of the technical qualification requirements in 2011, which are different to the RCC-M qualification process. This qualification required additional chemical and mechanical characterizations in the segregated area of the representative vessel head. The additional Charpy-V test did not meet the 60 J requirement of the ESPN order and led to the large testing program to characterize the toughness properties of the segregated material.

scholarly journals Investigation on Mechanical Properties of Graphene Reinforced Jute Fibre Reinforced Polymer Composites

2020 ◽  
Author(s):  
Rathinasabapathi G ◽  
Krishnamoorthy A
Keyword(s):  
Mechanical Properties ◽  
Fatigue Strength ◽  
Impact Strength ◽  
Mechanical Tests ◽  
Layered Composite ◽  
Fiber Reinforced Polymer ◽  
Jute Fibre ◽  
Reinforced Polymer ◽  
Fibre Reinforced Polymer ◽  
The Impact

In this study, the impact of adding Graphene Nano Platelets on the mechanical properties of Jute Fiber reinforced Polymer (JFRP) composites has been investigated. JFRP composite specimens were fabricated with varying number of layers (3 Layers, 4 Layers, and 5 Layers) and different orientations (30 degree, 45 degree, 60 degree) reinforced with 2% weight graphene nano platelet. Ultrasonicator is used for dispersion of graphene nano platelets into the epoxy matrix. Mechanical Tests namely Tensile test, flexural test and impact test is carried out to study the behavior of JFRP with different layers and orientations. The results proved that the use of 2% weight of Graphene Nano platelets led an enhancement in fatigue strength and impact strength. Also it is found that 3 layered with 30 degree orientation composite specimens had better mechanical properties compared to 4 layered and 5 layered composite specimens.

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