scholarly journals Microstructural and Mechanical Characterization of W-CuCrZr Joints Brazed with Cu-Ti Filler Alloy

Metals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 202
Author(s):  
Javier de Prado ◽  
María Sánchez ◽  
David Swan ◽  
Alejandro Ureña
Keyword(s):  
Mechanical Properties ◽  
Power Plants ◽  
Pure Shear ◽  
High Vacuum ◽  
Base Material ◽  
Mechanical Tests ◽  
Vacuum Furnace ◽  
Shear Loads ◽  
Microhardness Profile ◽  
Brazed Joint

The determination of the mechanical properties of a brazed joint is an important factor to reach the metallurgical level of a joint development. This paper evaluates the mechanical properties, and its correlation with the joint microstructure, of a W-CuCrZr joint brazed in a high vacuum furnace using 80Cu-20Ti flexible filler material in tape form. This joint is meant to be implemented in the divertor application in future fusion power plants. Main experimental parameters were a brazing temperature of 960 °C and a dwell time of 10 min. The microstructure of the joint was constituted by Cu solid solution and Cu4Ti phases. This last phase was distributed in the W-braze interface. Mechanical properties were evaluated by means of Vickers microhardness and mechanical tests by applying pure shear loads. The microhardness profile of the brazed joint indicated that W remained with the as-received hardness but CuCrZr base material was softened after the brazing procedure. Shear strength of 96 ± 15 MPa was obtained for the brazed joint and fracture propagated at the W-braze interface.

Synthesis of powder metallurgy Ti-3Fe-2Al alloy using high-frequency induction heating

2019 ◽  
Vol 34 (01n03) ◽  
pp. 2040031
Author(s):  
Stella Raynova ◽  
Khaled Alsharedah ◽  
Fei Yang ◽  
Leandro Bolzoni
Keyword(s):  
Mechanical Properties ◽  
Powder Metallurgy ◽  
Induction Heating ◽  
High Frequency ◽  
High Efficiency ◽  
High Vacuum ◽  
Residual Porosity ◽  
Effect Of Temperature ◽  
Vacuum Furnace ◽  
High Frequency Induction

A powder metallurgy approach was applied for the synthesis of an [Formula: see text] Ti-2Al-3Fe alloy. Blends of the elemental Ti, Al and Fe powders were compacted and subsequently sintered. High-frequency induction heating (HFIH) instead of conventional high-vacuum furnace heating was used for the sintering, due to its high efficiency. The effect of temperature on the level of densification, residual porosity and mechanical properties was studied. Electron dispersive spectrum analysis was used to study the dissolution and homogenization of the alloying elements. The results showed that a short induction sintering (IS) cycle in the range of 10–15 min is sufficient to achieve significant powder consolidation, evident by the increase of the density and mechanical properties. The residual porosity diminishes with the increase of the sintering temperature. Full dissolution of the alloying powders is completed after sintering at temperatures above those of [Formula: see text]- to [Formula: see text]-phase transformation.

GTAW Welded Inconel 625 Alloy Fuel Cladding for the Canadian SCWR: Microstructure and Mechanical Property Characterization

2020 ◽  
Author(s):  
German Cota-Sanchez ◽  
Lin Xiao
Keyword(s):  
Mechanical Properties ◽  
Grain Growth ◽  
Dendritic Structure ◽  
Base Material ◽  
Mechanical Tests ◽  
Nuclear Industry ◽  
Reactor Fuel ◽  
Inconel 625 ◽  
Fuel Cladding ◽  
Inconel 625 Alloy

Abstract Inconel 625 is considered one of the candidate materials for reactor fuel cladding in the Canadian supercritical water reactor (SCWR) design. Gas tungsten arc welding (GTAW) is being evaluated as a joining technique for SCWR fuel cladding since this method is widely used to join components in the power and nuclear industry. During the GTAW process, the welding thermal cycle produces different types of microstructures in both the heat-affected zone (HAZ) and fusion zone (FZ) that affect the material's mechanical properties. A series of welding experiments at various weld conditions were performed using an automatic GTAW orbital process on Inconel 625 alloy tubing. Simple analytical heat conduction and grain growth models were developed to predict weld temperature profiles and metallurgical transformations. Weld characterization included mechanical tests, optical microscopy, scanning electron microscopy - energy dispersive spectroscopy (SEM-EDS) elemental analysis, and microhardness measurements. Weld microstructural characterization revealed that a characteristic dendritic structure was formed in the FZ, while the HAZ exhibited larger equiaxed grains than those found in the base material. SEM-EDS analysis showed no distinct alloying element segregation in both the HAZ and FZ. Welds produced with heat inputs of about 3.00 kJ/cm3 presented similar mechanical properties as those observed in the base material. In these welds, grain growth was homogenously minimized in the FZ. It is concluded that the effective welding heat input control can optimize the weld microstructure and the weld mechanical properties in Inconel 625 tubing used as Canadian SCWR reactor fuel cladding.

Effect of environment on mechanical properties of micron sized beams of bone fabricated using FIB

2010 ◽  
Vol 1274 ◽  
Author(s):  
Asa H Barber ◽  
Ines Jimenez-Palomar
Keyword(s):  
Mechanical Properties ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
High Vacuum ◽  
Structural Features ◽  
Mechanical Tests ◽  
Length Scales ◽  
Bone Material ◽  
Force Microscopy ◽  
Atomic Force

AbstractBone is a complex material with structural features varying over many different length scales. Lamellae in bone are discrete units of collagen fibril arrays that are the dominant structural feature at length scales of a few microns. The mechanical properties of bone are importantly dependent on the synergy between the lamellae and structural features at other length scales. However, the mechanical properties at this micron level will be indicative of the bone material itself and ignores the structural and geometric organizations prevalent at larger length scales. The isolation of volumes of bone at the lamellar level requires precision cutting methodology and this paper exploits Focused Ion Beam (FIB) methods to mill small cantilever beams from bulk bone material. Importantly, FIB milling can only be performed in a relatively high vacuum environment. Atomic Force Microscopy (AFM) mechanical tests are therefore performed in two environments, high vacuum and air in order to assess the effects of vacuum on bone beam mechanical behaviour. Our results indicate that little difference in the bone beam elastic modulus is found from bending experiments at deflections up to 100nm in different environments.

Research on GTAW/SMAW Weldability of ADI/DI Using Electrodes ENi-Cl and ENiFe-Cl-A

2015 ◽  
Vol 1128 ◽  
pp. 242-253
Author(s):  
Ioan Catalin Mon ◽  
Mircea Horia Tierean ◽  
Adel Nofal
Keyword(s):  
Mechanical Properties ◽  
Tensile Test ◽  
Ductile Iron ◽  
Arc Welding ◽  
Filler Metal ◽  
Welded Joint ◽  
Base Material ◽  
Mechanical Tests ◽  
X Rays ◽  
Gtaw Process

The present research is dedicated to weldability of Austempered Ductile Iron (ADI) and Ductile Iron (DI) using Shielded Metal Arc Welding (SMAW) and Gas Tungsten Arc Welding (GTAW) methods. The welds were done using the arc welding process with Nickel base filler materials: ENi-Cl and ENiFe-Cl-A. Each weldment was examined visually, with X-rays and mechanical tests. After the mechanical tests, tensile test and impact properties of the welded joint are lower than mechanical properties of the ADI base material using ENiFe-Cl-A filler metal and GTAW process. This type of filler metal ENiFe-Cl-A can be applied successfully only for repair by welding of ADI parts. Using ENi-Cl filler metal with GTAW process applied to DI, the mechanical tests, tensile test and hardness of the welded joint are greater than mechanical properties of the DI base material. This procedure can be applied for welding. In case on DI welded using SMAW with ENi-Cl electrodes, the hardness of the welded joint is lower than the hardness of base material. This procedure can be applied only for repair by welding.

scholarly journals Electro mechanical properties changes of LDPE doped with industrial type MgO for cable insulation purposes

2021 ◽  
Vol 23 (3) ◽  
pp. 1315
Author(s):  
Sherif Haggag ◽  
Loai Nasrat ◽  
Hanafy Ismail
Keyword(s):  
Mechanical Properties ◽  
Base Material ◽  
Volume Resistivity ◽  
Dielectric Strength ◽  
Mechanical Tests ◽  
Filler Loading ◽  
Melt Flow Rate ◽  
Electrical Test ◽  
Cost Impact ◽  
Electrical Cables

<p>This manuscript introduces the changes of a comprehensive electromechanical properties bundle for low density polyethylene compounded to microscale magnesia (LDPE/MgO) to obtain electrical cables insulating material. Composites of various filler loading weight ratios were prepared by melt intercalation technique; multiple samples were produced in sets as they were cut with definite dimensions as per recommendations of the related testing standard then electrically and mechanically examined following the instruction dictated by the code while preserving typical test condition for all sets. Dielectric strength, volume resistivity, capacitance, and loss angle were the tests of the electrical test pack, while elongation, tensile strength, and melt flow rate were the mechanical and rheological tests applied. Test’s findings were compared to each other’s and to the base material to identify the differentiation. Electrical test results show improvements in the composite features at low loading percentages, whereas the mechanical tests revealed a deterioration in the mechanical properties along with all ratios under investigation. The research aims to determine the compositing benefit extents and drawbacks when a conventional compounding method and inexpensive filler are used, incurring marginal cost impact.</p>

Evaluation of Mechanical Properties of the Reactor Pressure Vessel Materials Changes by Small Punch Test Application

2013 ◽  
Author(s):  
Jana Petzová ◽  
Martin Březina ◽  
Ľudovít Kupča
Keyword(s):  
Mechanical Properties ◽  
Pressure Vessel ◽  
Nuclear Power ◽  
Power Plants ◽  
Mechanical Tests ◽  
Reactor Pressure Vessel ◽  
Small Punch Test ◽  
Small Punch ◽  
Punch Test ◽  
Reactor Pressure

The reactor pressure vessel (RPV) is the most important component of nuclear power plants. RPV steel near the reactor core is subject of irradiation degradation due to the fast neutron flux. Irradiation processes are rather complex but after all the damage of the steel crystal lattice lead to the changes of RPV mechanical properties as well as the shift of the transition temperature to higher values. Hence, monitoring of the RPV material irradiation changes must be proved during the all nuclear power plant (NPP) operation. The new surveillance specimen programs (SSP) at all Slovak NPPs reactors included, among the standard mechanical tests, also new types of evaluation mechanical properties due to method Small Punch Test (SPT).

Availability of Resilient Modulus and Permanent Deformation Laboratory Tests of Stabilized Soil with Coal Ashes for Pavements Base

2012 ◽  
Vol 517 ◽  
pp. 570-576 ◽  
Author(s):  
L.S.E. Lopes ◽  
P. Vargas ◽  
M.D.T. Casagrande ◽  
L.M.G. Motta
Keyword(s):  
Mechanical Properties ◽  
Power Plants ◽  
Resilient Modulus ◽  
Permanent Deformation ◽  
Thermal Power ◽  
Bottom Ash ◽  
Base Material ◽  
Coal Ash ◽  
Stabilized Soil ◽  
Ash Disposal

Fly and Bottom ash a coal combustion residue of thermal power plants has been regarded as a problematic residue all over the world. This study presents the results of testing for resilient modulus and permanent deformation to evaluate the mechanical properties of a soil stabilized with fly or bottom ashes, with and without lime addition. The soil tested is a regional sandy soil, which is not suitable for use in pavement works. The addition of fly ash with lime improved their mechanical properties, these being dependent on the ash content, moisture and number of load cycles. However in the mixtures only with ashes, the improvement was lower than the mixtures with ashes and lime. It was performed a paving project to assess their competitiveness as a base material for pavements. The results of this project showed that the soil stabilized with ashes is competitive for low volume traffic roads, with the advantages of minimizing the environmental problems caused by coal ash disposal.

Evaluation of Critical Resolved Shear Stresses for Various Plastic Deformation Mechanisms To Understand Mechanical Properties of Magnesium-Yttrium Alloys

2015 ◽  
Vol 1741 ◽  
Author(s):  
T. Mineta ◽  
S. Miura
Keyword(s):  
Mechanical Properties ◽  
Solid Solution ◽  
Plastic Deformation ◽  
Basal Slip ◽  
Pure Shear ◽  
Mechanical Tests ◽  
Deformation Mechanisms ◽  
Solid Solution Alloy ◽  
Shear Stresses ◽  
Von Mises

ABSTRACTIn order to understand enhanced mechanical properties of magnesium-yttrium (Mg-Y) alloys, applied stresses which were required to operate independent plastic deformation mechanisms on various stress axes were evaluated. Moreover, for this analysis, mechanical tests including newly-established testing method “pure-shear test” were conducted to evaluate Critical Resolved Shear Stresses (CRSSes) for various plastic deformation mechanisms of Mg-Y solid solution alloy single crystals with various Y concentration. Relatively higher solid solution strengthening of dominant plastic deformation mechanisms such as basal slip and extension twin at room temperature, results in increase in the activation of non-basal slip system. By a simple analysis based on von-Mises criterion with experimental CRSS values, it is revealed that enhanced mechanical properties of Mg-Y alloys might be attributed to the decrease of difference in the activity of plastic deformation mechanisms by Y addition.

Relaxation of Exemption Requirement of PWHT for SA-508 Grade 1A, by Consideration Surface Welding Residual Stress As Evaluated by Instrumented Indentation Testing Method

2017 ◽  
Author(s):  
Jong-hyoung Kim ◽  
Jun Sang Lee ◽  
Sungki Choi ◽  
Jong-sung Kim ◽  
Dongil Kwon
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Residual Stress ◽  
Power Plants ◽  
Mechanical Tests ◽  
Pressure Vessels ◽  
Post Weld Heat Treatment ◽  
Welding Residual Stress ◽  
Acceptance Criterion ◽  
Weld Heat

Generally, post-weld heat treatment is applied to decrease welding residual stress and improve the mechanical properties and microstructure of weldment, and its performance has been recommended for many years [1, 2]. However, current steel-making technology has improved significantly and, steel toughness levels have generally improved substantially [1]. Additionally for several quenched and tempered steels, it is reported that in some cases, mechanical properties such as tensile strength and impact toughness are degraded after post-weld heat treatment [3]. In addition, for large steel assemblies, post-weld heat treatment can be expensive, so that there is an economic incentive to avoid post-weld heat treatment [2]. The research presented here suggests a way to exempt post-weld heat treatment for SA-508 Grade 1A material, which is used for pressure vessels in nuclear power plants, by considering both mechanical properties and residual stress to simplify the welding procedure. Weldments made of 120 mm thick SA-508 Grade 1A should be post-weld heat treated, according to current ASME BPV Code. In order to increase the PWHT exemption thickness to 120 mm, we performed mechanical tests using welding coupons without PWHT; the test results satisfied current mechanical property criteria. We present a residual stress acceptance criterion based on brittle fracture criteria in this research.

TiO2 Nanoparticle Addition into Molten Steel: From Lab Scale to Industrial Scale

2014 ◽  
Vol 783-786 ◽  
pp. 813-817 ◽  
Author(s):  
Idurre Kaltzakorta ◽  
Lorena M. Callejo ◽  
Zuriñe Idoyaga
Keyword(s):  
Mechanical Properties ◽  
Molten Metal ◽  
Molten Steel ◽  
Pure Iron ◽  
Microalloyed Steel ◽  
New Technology ◽  
High Vacuum ◽  
Vacuum Furnace ◽  
Industrial Level ◽  
Iron Bath

In this work, the design of a new technology for nanoparticle addition into molten steel that improves the mechanical properties of the material, as well as the upscale of the process, was pursued. The process was scaled from laboratory to industrial level starting from first experiments carried out in pure iron bath, in order to analyze the behavior of nanoparticles in molten metal environment, and finishing with the addition of nanoparticles into microalloyed steel bath as industrial trials. The first steps of the research were performed in the levitation furnace at Tecnalia R&I installations that can cast samples up to 1 kg, continuing with a high vacuum furnace with a capacity up to 35 Kg. By the end of the investigation, the process was scaled up to industrial level at Gerdau facilities.

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