Search Results for nuclear reactors

The corrosion of structural materials and control of coolant chemistry are key factors that impact the lifetime of nuclear reactors and the development of future reactors. This article reviews corrosion issues in four reactor concepts that use vastly different coolant types: light water reactors, lead fast reactors, high temperature gas-cooled reactors, and fluoride salt-cooled high temperature reactors.

Researchers at Pacific Northwest National Laboratory (PNNL) use a combination of scanning and transmission electron microscopy, atom probe tomography, and focused ion beam milling to analyze corrosion and crack structures in light-water reactor components with near-atomic spatial resolution.

Laser powder bed fusion (LBFP) additive manufacturing is a potential route for the rapid qualification of new materials for use in nuclear reactor design. Process anomalies such as spatter particles can induce lack of fusion (LOF) voids that may adversely affect the material's mechanical performance. This examination of the spatter particle process in a nickel superalloy using X-ray computed tomography and optical microscopy was conducted to identify possible causes for the formation of LOF voids and other variations during LBPF processing.

Cold spraying is a potentially attractive method for producing accident tolerant fuel cladding, near-net shape nuclear reactor components, and nuclear fuel storage canisters.

Enhancement of the diffusion bonding process for the development of compact heat exchangers (CHXs) provides an energy efficient solution for high-temperature applications in advanced nuclear reactors and other technologies. However, available information is limited concerning the diffusion bonding (and manufacturing) of CHXs in high temperature applications and associated selection of bonded materials, bonding conditions, mechanical performance, and thermo-fluid characteristics. This article reviews the available knowledge and the ongoing research being conducted to address gaps in information and application.

Zircotec Ltd., UK, originally developed its technologies for use in nuclear reactors. During the last decade, its coatings have been used in several other applications, including orthopedic implants, and the company has expanded into the defense sector with a greater emphasis on heat protection. This Technical Spotlight outlines some of the company's process capabilities.

Development of new, radiation-tolerant materials that maintain the structural integrity and safety margins over the course of a nuclear power reactor’s service life requires the ability to predict degradation phenomena. Modern post-irradiation examination methods make use of specialized high-flux test reactors and dedicated characterization facilities to limit occupational exposure and prevent the spread of radioactive contamination. This article illustrates the use of these advanced techniques to characterize precipitates in neutron-irradiated Fe-Cr-Al alloys.

This article describes work being done at the University of Limoges to develop thermal spray coatings for use in new nuclear power plant designs.

Nondestructive evaluation comprises a large family of specific test disciplines including visual inspection, dimensional metrology, ultrasound, radiography, penetrant tests, magnetic particle tests, leak tests, eddy current tests, potential drop tests, flash and vibrothermography, shearography, acoustic emissions, and many other methods. This article offers an overview of NDE science and discusses some key considerations for choosing specific techniques.

A novel brazing approach for joining SiC-based fuel cladding is a promising technology for enhanced accident-tolerant nuclear fuels.

For those who are active within the thermal spray industry, 2017 offered a dramatic mix of jubilation and concern over conditions within the global thermal spray market. This article briefly reviews some of the market factors influencing the industry in 2017 and future outlook.

Cold spray was primarily developed for use in applications that are extremely sensitive to high process temperatures. Due to this factor and its other unique capabilities, cold spray is becoming attractive as an enabling technology for 3D printing or additive manufacturing. Current work is focusing on reducing the spot size of cold spray systems to enable them to produce more intricate and highly finished shapes.

Radio frequency inductively coupled plasma (RF-ICP) spraying is shown to be a promising method for producing oxidation-resistant W and W-Cr coatings on plasma-facing surfaces in fission and fusion reactors.

Recent advances in neutron sources and detector technologies enable new contrast mechanisms to determine crystalline information for metal components. This new capability can help validate emerging additive manufacturing processes used to produce parts with complex geometries.

Optimizing the integrity and performance of highly engineered surfaces and structures requires the ability to visualize and understand material behavior over multiple length and time scales from a three-dimensional perspective. The Electron Microscopy Centre at the University of Manchester is equipped for such work as demonstrated in problem-solving scenarios involving multiscale imaging and analysis of the progression of intergranular corrosion in Al alloy 2024, the catalytic effect of silver nanoparticles in seawater, recrystallization in a volume element of a bronze alloy, and defect progression on graphene surfaces.

The development of polymers, traditionally neglected in fusion materials research, is crucial to the success of commercial fusion energy. This article provides an overview of the materials science and technology challenges that will need to be addressed to develop the mechanically “soft” materials that will serve functional needs in a fusion pilot plant.

Development of wear-resistant hardfacing materials using powder metallurgy/hot isostatic pressing technology offers an alternative to today's cobalt-based materials and those that suffer delamination damage. Ongoing research and development at the Electric Power Research Institute (EPRI), detailed in this article, examines the application of wear-resistant hardfacing materials using the PM/HIP process. The hope is to eliminate weldability and residual stress challenges associated with some hardfacing alloys, as well as to provide a wider range of potential alloy solutions to reduce cobalt use and to address delamination issues with incumbent materials.

Thermal spray plays an important but latent role in many energy generation applications. Strong R&D commitment is required to further expand its technological envelope. This article addresses future directions in the use of thermal spray coating technologies in the energy sector.

Beryllium won a lengthy competition as the material of choice for the mirrors on the James Webb Space Telescope, set to launch in 2018. This article documents the development history leading up to that decision. It took decades to perfect powder atomization and HIP'ing processes to make optical-grade beryllium components homogeneous, isotropic, polishable, thermally and dimensionally stable, and above all, predictable.

News about ASM members, chapters, events, awards, conferences, affiliates, and other society activities. Topics include: ASM launches its latest affiliate society, the Failure Analysis Society; ASM partners with Zeiss in enhancing the ASM education facilities; volunteer profile for Merna Salama.