The welding process has a significant impact on the chemical composition, structure and mechanical properties of materials in heat-affected zones. The existing approaches to the diagnostics cannot predict the properties of the welded joint nor do they guarantee its reliable performance throughout the projected service life. This becomes especially relevant when investigating the welds from heterogeneous steels applied in power engineering. The main goal of this paper is to offer modern approaches to the complex technical diagnostics of steam pipelines using X-ray investigation of heterogeneous weld structures. In this work, the following research methods were used: X-ray fluorescence analysis, X-ray diffraction method, and microhardness measurement. The object of the investigation is the composite weld of 12Cr18Ni9Ti austenitic steel and 12Cr1MoV pearlitic steel. The results of this investigation show that the properties of the weldable steel changed significantly as compared to its original state. The weld structure was represented by the internal structural stress gradients despite the application of the stress relief heat treatment. The proposed approaches to the study of steel welds can be used for selecting the rational mode of post-weld heat treatment. Combined with traditional inspection methods (visual or ultrasonic inspection, etc.), these approaches can serve as a basis for technical diagnostics and the selection of constructional materials.

X-ray investigation of a heterogeneous steel weld

The effect of thermo-mechanical loading on fracture-related parameters of austenitic steel

Welding joints of dissimilar steels don’t withstand design life. One of the important causes of premature destructions can be the acceleration of steel structural degradation due to cyclic mechanical and thermal gradients. Two zones of tube from steel 12H18N9T, exhibiting the structural instability at early stages of the decomposition of a supersaturated solid austenite solution, were subjected to investigation. Methods of x-ray spectral and structure analysis, micro hardnessmetry were applied for the research. Made the following conclusions, inside and outside tube wall surfaces of hazardous zones in welding joint have different technological and resource characteristics. The microhardness very sensitive to changes of metal structure and can be regarded as integral characteristic of strength and ductility. The welding processes are responsible for the further fibering of tube wall structure, they impact to the characteristics of hot-resistance and long-term strength due to development of ring cracks in the welding joint of pipeline. The monitoring of microhardness and structural phase conversions can be used for control by changes of mechanical properties in result of post welding and reductive heat treatment of welding joints.

/pdf/the-investigation-of-structure-heterogeneous-joint-welds-in-2meis38sqv.pdf

The Investigation of Structure Heterogeneous Joint Welds in Pipelines

This paper presents new approaches to solving problems of forecasting the life of heating surface of boilers, based on an analysis of internal structural stresses of the first and second kind that could affect the intragranular and intergranular strength and reliability of the pipeline in continuous operation by making it work without damage by preventing the disclosure of zone cracks.

/pdf/connection-between-internal-structural-stresses-of-the-ist-560st4w605.pdf

Connection Between Internal Structural Stresses of the Ist and the IInd kind and Operational Reliability of the Boiler Heating Surface

The effect of metal corrosion on the third-order microscopic properties, i.e., the root-mean-square deviation and internal residual stresses of the first-order, was studied. The corrosion process was studied on steel specimens under conditions of superheated steam (250°C) during 500 h. The X-ray diffraction method was taken as the basic research method. The process of corrosion failure was concluded to have two reproducible periods: the period of active metal dissolution and latent passivation period, followed by the corrosion initiation phase. The metal passivity occurs due to the compressive stresses.

Microstructural Aspects of Corrosion

The article presents information on local structural nonuniformities in the tube wall metal due to which its individual zones have different susceptibility to corrosion damage processes. The presented information is based on experimental data about the structure of material (microhardness, crystallite size distribution function, and inner structural stresses of the first and second kind depending on the structural flaws density and temperature) obtained using the high-temperature X-radiography method. For a sample made of Grade 20 steel, the temperature range (350–370°C) is experimentally substantiated and determined based on the conditions of relaxing inner structural stresses of the first and second kind in which the crack surface is passivated by oxide film, which prevents the occurrence of stress concentration at the crack edge and crack propagation.

Consideration of intrastructural stresses in the processes connected with the effect of structural nonuniformity on corrosion damages inflicted to heat-transfer tubes

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.

A. A. Makeev

Author Tools

Chat about Author

Papers

Consideration of intrastructural stresses in the processes connected with the effect of structural nonuniformity on corrosion damages inflicted to heat-transfer tubes