Thermal aging behaviors of duplex stainless steels used in nuclear power plant: A review

In this study, the microstructure characteristics and formation mechanism of DSS (duplex stainless steel) multi-pass weld joints were firstly investigated in terms of the OM (optical microscope) and EBSD (electron back-scattered diffraction) observation, and a series mechanical tests, including the monotonic tensile tests assisted by the DIC (digital image correlation) observation and stress-controlled fatigue tests, were subsequently performed to clarify the intrinsic correlation between mechanical behavior and microstructure. The fatigue fracture morphologies and cracks propagation behavior were analyzed by the OM and SEM (scanning electron microscope) observation. The results show that the significant ferritiszation and determined precipitations were found at the HAZ (heat-affected zone), whereas the austenite was dominating at weld filler zone due to the more formation of the IGA (intragranular austenite). A nearly balance phase ratio was obtained at weld back and cap zones, but the strip GBA (grain boundary austenites) was connected into piece along thickness direction. The monotonic tensile strength of weld joints was higher than that of the based materials due to the refined-grains structures, and the final rupture occurred at the BM (based material) zone. However, the fatigue lifetimes of weld joints were much shorter than that of based materials for the same cyclic amplitude. The fatigue cracks preferred to nucleate at weld back or cap passes although where phase ratio was approximately balance. The austenitic grains which were connected into pieces accelerated the initiation of fatigue cracks. Apart from maintaining phases balance and avoiding detrimental precipitation, the alternative distribution of austenite and ferrite should also be obtained in the engineering.

Nonhomogeneous microstructure formation and its role on tensile and fatigue performance of duplex stainless steel 2205 multi-pass weld joints

Coupling effect of thermal aging and pre-strain on fracture behavior of SMAW welded joints

Combining global experience, comprehensive aging knowledge, and predictive methodologies provides ideal prerequisites for the long-term operation strategy (LTO) of a nuclear power plant (NPP). Applying management strategies with an understanding of the ways in which structures relevant for the plant safety perform and interact in their operating environments is of meaningful importance for operating the plant beyond its originally licensed service life. In performing aging studies on the nuclear systems, structure, and components (SSCs), the results are crucial for demonstrating the safety and reliability of the NPP beyond 30 years of nominal operation. In this study, the synergistic effect of a creep mechanism with the alteration suffered by piping material is analyzed by means of MSC©MARC finite element code. Nonlinear analyses were performed to calculate the effects of the long operational period on a primary pipe, assess its degradation, and determine its residual functionality. In these analyses, both homogeneous and inhomogeneous pipe wall thinning are considered, as well as the operating or expected thermal–mechanical loads. The obtained results indicate that thermo–mechanical loads are responsible for pipe deformation, which develops and increases as the transient progresses. Furthermore, an excessive (general or local) wall thinning may determine a dimensional change of the pipe, even causing bending or buckling.

Preliminary Analysis of Long-Term Performance of a Piping: Aging and Creep Effects.

The invention discloses a system and method for monitoring fatigue of a nuclear power plant and belongs to the technical field of nuclear power The system comprises a temperature data obtaining subsystem, a nuclear power plant digitization instrument control subsystem and a fatigue monitoring server, wherein the temperature data obtaining subsystem is used for measuring outer wall surface temperature of a pipeline or device in a fatigue sensitive area to obtain a temperature parameter of the outer wall surface; a nuclear power plant digitization instrument control subsystem is used for obtaining a fluid temperature parameter and a fluid pressure parameter in the pipeline or device; and the fatigue monitoring server is used for receiving the temperature parameter of the outer wall surface transferred by the temperature data obtaining subsystem and the fluid temperature parameter and the fluid pressure parameter transferred by the nuclear power plant digitization instrument control subsystem, wherein a real fatigue status of the pipeline or device is obtained through calculation based on the temperature parameter of the outer wall surface, the fluid temperature parameter and the fluid pressure parameter According to the system, a metal pipeline or device in a typical fatigue sensitive area of the nuclear power plant is monitored in real time to obtain the real fatigue status of the pipeline or device so as to perform early warning for the pipeline or device with possible fatigue damage

System and method for monitoring fatigue of nuclear power plant

Thermal aging effect on the tensile and fatigue properties of the narrow-gap TIG welded joints in offshore floating nuclear power plants

Long-term thermal aging performance of welding structures in primary coolant pipes for nuclear power plants

Test bed for simulating thermal fatigue phenomenon of nuclear power station pipeline

The utility model provides a test rack for simulating pipeline thermal fatigue phenomenon of a nuclear power plant, which comprises a heating system, a cooling system, a T-shaped pipeline and valve system and a measurement and control system; the heating system mainly comprises a thermal fluid storage tank, a high-level thermal fluid box, a thermal fluid pump and a first thermometer arranged in the high-level thermal fluid box; the cooling system mainly comprises a cold fluid storage tank, a high-level cold fluid box, a cold fluid pump and a second thermometer arranged in the high-level cold fluid box; the T-shaped pipeline and valve system mainly comprises a three-way T-shaped pipe, an upper electromagnetic valve and a lower electromagnetic valve arranged horizontally; and the measurement and control system mainly comprises a first temperature controller, a second temperature controller, a first flowmeter, a second flowmeter and a control and acquisition system. The test rack for simulating the pipeline thermal fatigue phenomenon of the nuclear power plant disclosed by the utility model is capable of simulating generation and development of the pipeline thermal fatigue phenomenon of the nuclear power plant, playing a role of supporting measurement and evaluation of the pipeline thermal fatigue phenomenon of the nuclear power plant, and being beneficial to application and research of technical engineering.

Test rack for simulating pipeline thermal fatigue phenomenon of nuclear power plant

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Min Yu

Author Tools

Chat about Author

Papers

Thermal aging effect on the tensile and fatigue properties of the narrow-gap TIG welded joints in offshore floating nuclear power plants

Long-term thermal aging performance of welding structures in primary coolant pipes for nuclear power plants

Test bed for simulating thermal fatigue phenomenon of nuclear power station pipeline

Test rack for simulating pipeline thermal fatigue phenomenon of nuclear power plant