Browsing NTNU Open by Author "Alvaro, Antonio"
Now showing items 1-20 of 23
-
3D Cohesive Modelling of Hydrogen Embrittlement in the Heat Affected Zone of X70 Steel
Alvaro, Antonio (Doktoravhandlinger ved NTNU, 1503-8181; 2014:53, Doctoral thesis, 2014) -
A uniform hydrogen degradation law for high strength steels
Yu, Haiyang; Olsen, Jim Stian; Alvaro, Antonio; Olden, Vigdis; He, Jianying; Zhang, Zhiliang (Journal article; Peer reviewed, 2016)The degrading effect of hydrogen on high strength steels is well recognized. The hydrogen degradation is dependent not only on hydrogen content, but also on geometric constraints or equivalently, level of stress triaxiality, ... -
Cohesive zone simulation of grain size and misorientation effects on hydrogen embrittlement in nickel
Yu, Haiyang; Olsen, Jim Stian; Olden, Vigdis; Alvaro, Antonio; He, Jianying; Zhang, Zhiliang (Journal article; Peer reviewed, 2017)The size and misorientation effects on hydrogen embrittlement of a four grain nickel aggregate are studied with the help of hydrogen informed cohesive zone model. The grain misorientation angle is parameterized by fixing ... -
Complete Simulation Models to Describe the Ductile-to-Brittle Transition of Steels for Arctic Applications - A Beremin-Gurson Approach
Scheide, Henrik Andre (Master thesis, 2018)The toughness of common structural steels is often affected by temperature changes where low service temperatures frequently promote brittle material characteristics. Low service temperatures often occur in the Arctic ... -
Defining Local Stress-Strain Fields in Ductile Components under Cyclic Loading
Hofgaard, Marthe Elise (Master thesis, 2018)Subsea power cables consist of an extruded lead alloy sheathing, which act as a protective layer against water penetration. The lack of research and framework for advanced fatigue calculations of lead has made it difficult ... -
Experimental and numerical investigation of strain distribution of notched lead fatigue test specimen
Johanson, Audun; Viespoli, Luigi Mario; Nyhus, Bård; Alvaro, Antonio; Berto, Filippo (Journal article; Peer reviewed, 2018)The work here presented focuses on the test methodology related to effect of stress concentrators in strain controlled structures. Cable sheathing as used in subsea power cables are investigated by cyclic fatigue testing, ... -
EXPERIMENTAL AND NUMERICAL INVESTIGATIONS OF A LEAD ALLOY USED IN SUBSEA POWER CABLE
Sommacal, Alberto (Master thesis, 2018)Subsea Power Cable are used to carry electric power in marine environment, where are commonly installed on the seabed. The internal conductor is wrapped by electric insulation and several protective layers, among these a ... -
Fatigue investigation of complex weldments by the means of the local strain energy density approach
Viespoli, Luigi Mario; Alvaro, Antonio; Nyhus, Bård; Berto, Filippo (Journal article; Peer reviewed, 2018)The paper investigates the use of an energetic approach based on the strain energy density failure criteria to predict the fatigue life of welded joints in aluminum alloy. The cited criterion has already been proved valid ... -
Hydrogen Embrittlement in Fe3%Si, Visited by Nanomechanical Testing and Cohesive Zone Simulation
Olden, Vigdis; Hajilou, Tarlan; Kheradmand, Nousha; Barnoush, Afrooz; Alvaro, Antonio; Osen, Vidar (Chapter, 2016)This work is part of a multi scale computational and experimental approach in which first principle modelling, nanoscale experiments and continuum simulations are combined in order to represent hydrogen induced degradation ... -
Hydrogen Enhanced Fatigue Crack Growth Rates in a Ferritic Fe-3wt%Si Alloy
Alvaro, Antonio; Wan, Di; Olden, Vigdis; Barnoush, Afrooz (Journal article; Peer reviewed, 2018)It is well known that the presence of hydrogen in ferrous materials promotes both static fracture and affect the material fatigue crack growth rates. The latter is often referred to as Hydrogen Enhanced Fatigue Crack Growth ... -
Hydrogen enhanced fatigue crack growth rates in a ferritic Fe-3 wt%Si alloy and a X70 pipeline steel
Alvaro, Antonio; Wan, Di; Olden, Vigdis; Barnoush, Afrooz (Journal article; Peer reviewed, 2019)It is well known that ferrous materials can be damaged by absorption of hydrogen. If a sufficient quantity of hydrogen penetrates into the material, static fracture and the material's fatigue performances can be affected ... -
Hydrogen informed Gurson model for hydrogen embrittlement simulation
Yu, Haiyang; Olsen, Jim Stian; Alvaro, Antonio; qiao, lijie; He, Jianying; Zhang, Zhiliang (Journal article; Peer reviewed, 2019)Hydrogen-microvoid interactions were studied via unit cell analyses with different hydrogen concentrations. The absolute failure strain decreases with hydrogen concentration, but the failure loci were found to follow the ... -
Hydrogen-assisted fatigue crack growth in ferritic steels – a fractographic study
Wan, Di; Alvaro, Antonio; Olden, Vigdis; Barnoush, Afrooz (Journal article; Peer reviewed, 2018)Fatigue crack growth (FCG) behavior of a Fe-3wt.%Si ferritic alloy under different environmental conditions using in-situ electrochemical (cathodic) hydrogen (H) charging has been investigated. Three frequencies have been ... -
Hydrogen-enhanced fatigue crack growth behaviors in a ferritic Fe-3wt%Si steel studied by fractography and dislocation structure analysis
Wan, Di; Alvaro, Antonio; Olden, Vigdis; Barnoush, Afrooz (Journal article; Peer reviewed, 2019)The effect of hydrogen (H) on the fatigue behavior is of significant importance for metallic structures. In this study, the hydrogen-enhanced fatigue crack growth rate (FCGR) tests on in-situ electrochemically H-charged ... -
Hydrogen-enhanced fatigue crack growth in a single-edge notched tensile specimen under in-situ hydrogen charging inside an environmental scanning electron microscope
Wan, Di; Deng, Yun; Meling, Jan Inge Hammer; Alvaro, Antonio; Barnoush, Afrooz (Journal article; Peer reviewed, 2019)Fatigue crack growth (FCG) test was done on a pre-cracked single-edge notched tensile (SENT) specimen with oligocrystalline ferritic structure. Innovative in-situ hydrogen (H)- charging by plasma inside an environmental ... -
Low-temperature fatigue life properties of Aluminum butt weldments by the means of the local strain energy density approach
Viespoli, Luigi Mario; Leonardi, Andrea; Cianetti, Filippo; Nyhus, Bård; Alvaro, Antonio; Berto, Filippo (Journal article; Peer reviewed, 2019)The paper investigates the use of the strain energy density evaluated on a finite control volume as a mean to the fatigue life prediction for double V‐groove but joints. The specimens are manufactured by metal active gas ... -
Material and Fatigue Life Investigation of a Lead Alloy used as Sheathing in Subsea Power Cables
Fotland, Gaute (Master thesis, 2017)Subsea power cables are used to transport electricity offshore. They consist of several layers, where a lead sheathing is used as the water barrier layer. From reeling and installation, in addition to daily cycles from ... -
Mechanical characterization of aluminum alloys for arctic structures application
Viespoli, Luigi Mario; Midling, Ole Terje; Alvaro, Antonio; Nyhus, Bård; Berto, Filippo (Journal article, 2020)Due to its low specific mass, mechanical resistance comparable to that of mild structural steels, the low maintenance cost and good corrosion resistance, aluminum alloys are well suited for the production of offshore ... -
Room temperature creep mechanism of a Pb-Sn-Sb lead alloy
Viespoli, Luigi Mario; Johanson, Audun; Alvaro, Antonio; Nyhus, Bård; Berto, Filippo (Journal article; Peer reviewed, 2019)Lead alloys are the most common materials adopted for the production of subsea power cable sheathing. The sheathing is a layer of stable and watertight metal, which serves to prevent the electrical failure of the cable. ... -
Small and Full-Scale Fatigue Testing of Lead Cable Sheathing
Johanson, Audun; Viespoli, Luigi Mario; Alvaro, Antonio; Berto, Filippo (Journal article, 2019)The fatigue behavior of a PbSnSb alloy used in subsea power cable sheathing was studied using small- and full-scale experiments. The aim of the work was to understand the transferability between the scales and suitable ...