Advances in Fracture, Fatigue and Structural Integrity Analyses of Metals

A special issue of Metals (ISSN 2075-4701). This special issue belongs to the section "Metal Failure Analysis".

Deadline for manuscript submissions: closed (31 December 2022) | Viewed by 17444

Special Issue Editors


E-Mail Website
Guest Editor
Laboratory of Materials Science and Engineering (LADICIM), Universidad de Cantabria, 39005 Santander, Spain
Interests: fracture; fatigue; structural integrity; notch mechanics; failure analysis
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
Laboratory of Materials Science and Engineering, Universidad de Cantabria, Santander, Spain
Interests: failure analysis

Special Issue Information

Dear Colleagues,

Given the good response of the scientific and technical communities to our previous Special Issue in Metals, entitled “Fracture, Fatigue and Structural Integrity of Metallic Materials” (2019), and given that research in these fields is continuously increasing in qualitative and quantitative terms, this new Special Issue intends to provide a forum for the dissemination of the latest significant advances in fracture, fatigue and structural integrity analyses.

Fracture, fatigue, creep or environmentally assisted cracking, among other critical and subcritical processes, still present many open issues. Attention is being paid from the very basic aspects explaining the material response at the atomic and microstructural scales to the development of engineering procedures defining the structural integrity conditions of a given structural component.

The application of all this newly developed knowledge affects a wide range of sectors where structural safety is a major concern: nuclear power plants, civil engineering structures, oil and gas, pressurized equipment, aircraft, naval structures, etc. Structural failures in any of these sectors may have evident serious consequences in terms of human lives, environmental disasters or economic losses. Therefore, in order to avoid structural failures, it is necessary to understand the different mechanisms generating critical and subcritical processes in the structural materials and to develop assessment techniques and management procedures for the corresponding structures.

In this context, this Special Issue is focused on the latest advances in fracture, fatigue and structural integrity assessments of metallic structural components containing defects (cracks, notches, local thin areas, etc.) and also on developments that are being or could be incorporated in structural integrity assessment procedures such as BS7910, R6 or API 579-1/ASME FFS-1. Contributions covering other damage and failure processes, such as creep, environmentally assisted cracking or buckling, that affect the structural integrity of engineering structures are also welcome.

We invite you to submit original research and review articles, as well as short communications, related to these topics.

Prof. Dr. Sergio Cicero
Dr. Sergio Arrieta
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Metals is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • fracture
  • fatigue
  • structural integrity
  • creep
  • environmentally assisted cracking
  • cracks
  • notches
  • nondestructive testing
  • local thin areas

Related Special Issue

Published Papers (7 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Editorial

Jump to: Research, Review

3 pages, 173 KiB  
Editorial
Advances in Fracture, Fatigue and Structural Integrity Analyses of Metals
by Sergio Arrieta and Sergio Cicero
Metals 2023, 13(5), 954; https://doi.org/10.3390/met13050954 - 15 May 2023
Viewed by 1027
Abstract
Given the good response of the scientific and technical communities to our previous Special Issue in Metals, titled “Fracture, Fatigue and Structural Integrity of Metallic Materials” (2019), and given that research in these fields is continuously increasing in qualitative and quantitative terms, [...] Read more.
Given the good response of the scientific and technical communities to our previous Special Issue in Metals, titled “Fracture, Fatigue and Structural Integrity of Metallic Materials” (2019), and given that research in these fields is continuously increasing in qualitative and quantitative terms, this new Special Issue intends to provide a forum for the dissemination of the latest significant advances in fracture, fatigue and structural integrity analyses [...] Full article

Research

Jump to: Editorial, Review

17 pages, 3113 KiB  
Article
Reduction of Residual Stresses in Cold Drawn Pearlitic Steel by a Soft Secondary Wire Diameter Reduction
by Jesús Toribio and Miguel Lorenzo
Metals 2023, 13(2), 433; https://doi.org/10.3390/met13020433 - 20 Feb 2023
Cited by 3 | Viewed by 1395
Abstract
In this paper, the effects of the skin pass technique on the residual stress and plastic strain fields generated in cold drawn pearlitic steel wires are analyzed. The aim is to find out the optimal conditions to be used in the design of [...] Read more.
In this paper, the effects of the skin pass technique on the residual stress and plastic strain fields generated in cold drawn pearlitic steel wires are analyzed. The aim is to find out the optimal conditions to be used in the design of a manufacturing process for obtaining more reliable structural components in terms of the main cause of failure: the hydrogen embrittlement (HE). To achieve this goal, diverse numerical simulations were performed by using finite elements (FE) and considering, on one hand, the first step of a real cold drawing chain, using (i) a conventional drawing die and (ii) modified drawing dies with different soft diameter reductions, and, on the other hand, numerical simulations by FE of the hydrogen diffusion assisted by stress and strain states to estimate the hydrogen distributions. Obtained results revealed the secondary reduction degree as a key parameter in the die design for reducing the drawing-induced residual stress. According to the results, low values of the reduction ratio cause radial distributions of residual stress with significant reductions at both the wire core and at the wire surface. In addition, the hydrogen accumulation at the prospective damage zone (near the wire surface) given by FE simulations is lower in the wires drawn with modified drawing dies including a skin pass zone. Full article
Show Figures

Figure 1

14 pages, 4109 KiB  
Article
Using Direct Current Potential Drop Technique to Estimate Fatigue Crack Growth Rates in Solid Bar Specimens under Environmental Assisted Fatigue in Simulated Pressurized Water Reactor Conditions
by Sergio Arrieta, Francisco Javier Perosanz, Jose Miguel Barcala, Maria Luisa Ruiz and Sergio Cicero
Metals 2022, 12(12), 2091; https://doi.org/10.3390/met12122091 - 6 Dec 2022
Cited by 2 | Viewed by 1801
Abstract
The direct current potential drop (DCPD) technique may be used in crack propagation tests to measure the crack growth rate (CGR). Potential probes attached to the specimen allow the variation of the crack length to be estimated. In this research, the DCPD technique [...] Read more.
The direct current potential drop (DCPD) technique may be used in crack propagation tests to measure the crack growth rate (CGR). Potential probes attached to the specimen allow the variation of the crack length to be estimated. In this research, the DCPD technique using one single potential probe was applied to solid bar specimens (i.e., without any initial notch or crack) subjected to low-cycle fatigue testing in a simulated pressurized water reactor (PWR) environment. This particular analysis had two associated difficulties, the first one being the fact that crack initiation sites are not known beforehand, and the second one consisting in the experimental difficulties and conditioning factors associated with the simulation of the PWR environment. Nine solid bar specimens were tested to fatigue failure under different strain amplitudes and frequencies, while also measuring the corresponding DCPD signal during the fatigue process. It was observed that the initiation of multiple cracks was detected by the DCPD measurements. Moreover, as fatigue continued, one of the cracks became dominant and progressed to cause the specimen failure. The DCPD technique allowed the average CGR of the dominant crack to be estimated. Finally, the obtained average CGRs were validated by comparing them with average CGRs derived from striation spacing measurements, obtained from scanning electron microscopy (SEM) and from literature values gathered in the NUREG/CR-6909 document. Full article
Show Figures

Figure 1

13 pages, 7376 KiB  
Article
Effect of Internal Hydrogen on the Fatigue Crack Growth Rate in the Coarse-Grain Heat-Affected Zone of a CrMo Steel
by Guillermo Álvarez, Alfredo Zafra, Francisco Javier Belzunce and Cristina Rodríguez
Metals 2022, 12(4), 673; https://doi.org/10.3390/met12040673 - 14 Apr 2022
Cited by 5 | Viewed by 2110
Abstract
The effect of internal hydrogen in the fatigue crack growth rate of the coarse grain region of a 2.25Cr1Mo steel welded joint was analyzed in this work. The microstructure of the coarse grain region was simulated by means of a heat treatment able [...] Read more.
The effect of internal hydrogen in the fatigue crack growth rate of the coarse grain region of a 2.25Cr1Mo steel welded joint was analyzed in this work. The microstructure of the coarse grain region was simulated by means of a heat treatment able to provide the same microstructure with a similar prior austenite grain size and hardness to the one in a real welded joint. The fatigue crack growth rate was measured under standard laboratory conditions using compact tensile (CT) specimens that were (i) uncharged and hydrogen pre-charged in a hydrogen pressure reactor (under 19.5 MPa and 450 °C for 21 h). The influence of fatigue frequency was assessed using frequencies of 10 Hz, 0.1 Hz, and 0.05 Hz. Additionally, two load ratios (R = 0.1 and R = 0.5) were applied to analyze their influence in the da/dN vs. ∆K curves and therefore in the fatigue crack growth rate. The embrittlement produced by the presence of internal hydrogen was clearly noticed at the beginning of the fatigue crack growth rate test (ΔK = 30 MPm), obtaining significant higher values than without hydrogen. This effect became more notorious as the test frequency decreased and the load ratio increased. At the same time, the failure mechanism changed from ductile (striations) to brittle (hydrogen decohesion) with intergranular fracture (IG) becoming the predominant failure mechanism under the highest loads (R = 0.5). Full article
Show Figures

Figure 1

9 pages, 1506 KiB  
Communication
Prediction of Work Hardening in Bearing Steels Undergoing Rolling Contact Loading with a Dislocation-Based Model
by Hongxiang Yin, Xue Bai and Hanwei Fu
Metals 2022, 12(4), 555; https://doi.org/10.3390/met12040555 - 25 Mar 2022
Cited by 5 | Viewed by 2467
Abstract
The work hardening behaviour of GCr15 bearing steel during rolling contact fatigue (RCF) is investigated. Ball-on-rod RCF tests and micro-indentation tests are performed to obtain various subsurface hardness profiles in rod specimens. It is found that orthogonal shear stress is responsible for work [...] Read more.
The work hardening behaviour of GCr15 bearing steel during rolling contact fatigue (RCF) is investigated. Ball-on-rod RCF tests and micro-indentation tests are performed to obtain various subsurface hardness profiles in rod specimens. It is found that orthogonal shear stress is responsible for work hardening under Hertzian contact and that the extent of hardness increase is positively associated with the stress level and number of cycles. A dislocation-based work hardening model is established by combining the Kocks–Mecking theory, the bearing steel plasticity equation and the Taylor relation. The proposed model is capable of predicting hardness changes with any given rolling contact stress state and number of cycles. The modelling results are compared against the experimental results, with good agreement obtained. This research also provides a methodology for studying the work hardening of different types of bearing steels undergoing RCF, from experiment to modelling. Full article
Show Figures

Graphical abstract

21 pages, 8045 KiB  
Article
Enhancing the Lifetime of the Pneumatic Cylinder in Automatic Assembly Line Subjected to Repeated Pressure Loading
by Seongwoo Woo, Dennis L. O’Neal and Yimer Mohammed Hassen
Metals 2022, 12(1), 35; https://doi.org/10.3390/met12010035 - 24 Dec 2021
Cited by 1 | Viewed by 3741
Abstract
This study demonstrates the application of parametric accelerated life testing (ALT) as a procedure to identify design deficiencies and correct them in generating a reliable quantitative (RQ) specification. It includes: (1) a system BX lifetime that X% of a product population fails with [...] Read more.
This study demonstrates the application of parametric accelerated life testing (ALT) as a procedure to identify design deficiencies and correct them in generating a reliable quantitative (RQ) specification. It includes: (1) a system BX lifetime that X% of a product population fails with a parametric ALT scheme, (2) fatigue design, (3) ALTs with alternations, and (4) judgement as to whether the design(s) secures the desired BX lifetime. A (generalized) life–stress model through the linear transport process and a sample size formulation are suggested. A pneumatic cylinder in a machine tool was used as a case study. The cylinder was failing in a flexible manufacturing system. To reproduce the failure and modify the design, a parametric ALT was performed. At the first ALT, the metal seal made of nickel-iron alloy (36% Ni) partially cracked and chipped and had a crisp metal sound. It was modified by changing the seal from a metal to a polymer (silicone rubber). At the second ALT, the piston seal leaked due to seal hardening and wear. The failure modes of the silicone seal in the laboratory tests were similar to those returned from the field. For the third ALT, the seal material was changed from silicone rubber to (thermoset) polyurethane. There were no concerns during the third ALT and the lifetime of the pneumatic cylinder was shown to have a B1 life of 10 years. Full article
Show Figures

Figure 1

Review

Jump to: Editorial, Research

20 pages, 2731 KiB  
Review
Rolling Contact Fatigue-Related Microstructural Alterations in Bearing Steels: A Brief Review
by Hongxiang Yin, Yi Wu, Dan Liu, Pengpai Zhang, Guanzhen Zhang and Hanwei Fu
Metals 2022, 12(6), 910; https://doi.org/10.3390/met12060910 - 26 May 2022
Cited by 9 | Viewed by 3553
Abstract
Bearings are vital components that are widely used in modern machinery. Although usually manufactured with high-strength steels, bearings still suffer from rolling contact fatigue where unique microstructural alterations take place beneath the contact surface as a result of the complex stress state. Studying [...] Read more.
Bearings are vital components that are widely used in modern machinery. Although usually manufactured with high-strength steels, bearings still suffer from rolling contact fatigue where unique microstructural alterations take place beneath the contact surface as a result of the complex stress state. Studying these microstructural alterations is a hot research topic with many efforts in recent decades. In this respect, the key information regarding four major types of microstructural alterations, white etching areas/white etching cracks, dark etching regions, white etching bands and light etching regions is reviewed regarding the phenomenology and formation mechanisms. Then, classical and state-of-the-art models are established to predict their formation and are summarised and evaluated. Based on the current research progress, several key questions and paradoxes for each type of microstructural alteration are raised, suggesting possible research directions in this field. Full article
Show Figures

Graphical abstract

Back to TopTop