Browsing NTNU Open by Author "Viespoli, Luigi Mario"
Now showing items 1-20 of 21
-
Creep and high temperature fatigue performance of as buildselective laser melted Ti-based 6Al-4V titanium alloy
Viespoli, Luigi Mario; Bressan, Stefano; Itoh, Takamoto; Hiyoshi, Noritake; Prashanth, Konda Gokuldoss; Berto, Filippo (Peer reviewed; Journal article, 2020)The present work focuses on the room and high temperature low-cycle fatigue and creep testing of Ti-6Al-4V manufactured by selective laser melting (SLM) or laser-based powder bed fusion process (LBPF). The fatigue specimens ... -
Cruciform welded joints: hot-dip galvanization effect on the fatigue life and local energetic analysis
Viespoli, Luigi Mario; Mutignani, Francesco; remes, heikki; filippo, berto (Journal article; Peer reviewed, 2018)Even in a well-controlled technological process, a certain variability in the final product is present and this is very well the case of welded joints, where each single joint is slightly different from the others in terms ... -
Ductile tearing of cryogenic valve components
Viespoli, Luigi Mario; Ingebo, Pål Idar; Berto, Filippo (Peer reviewed; Journal article, 2020)The paper reports the result of an experimental investigation on the torsional failure mechanics of the rotating components of a cryogenic valve. The rotating assembly is composed of an AISI 316L shaft connected by two ... -
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, ... -
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 ... -
Fatigue life assessment for a welded detail: advantages of a local energetic approach and experimental validation
Viespoli, Luigi Mario; Berto, Filippo; Soma, Aurelio (Journal article; Peer reviewed, 2018)In modern civil buildings, as well as in mechanical and naval constructions, welding is a widely diffused technological process. The fatigue assessment, as design or verification procedure, of a welded joint to evaluate ... -
Fatigue Life Prediction of Welded Joints for Industrial Applications - Overview on the regulations and extension to Fracture Mechanics
Viespoli, Luigi Mario (Master thesis, 2017)1) An overview on the fatigue assessment procedures for welds 3 1.1) Basic principles 3 1.2) Determining the stresses and the stress intensity factors 5 1.2.1) Nominal Stress approach 6 1.2.2) Structural Hot Spot Stress ... -
Fatigue Strength Assessment of Steel Rollers: On the Reliability of the Strain Energy Density Approach on Real Components
Chebat, F.; Peron, Mirco; Viespoli, Luigi Mario; Welo, Torgeir; Berto, Filippo (Journal article; Peer reviewed, 2018)Welded joints are one of the most widely applied methods to join different steel components. However, they introduce stress concentrators that are commonly known to reduce the fatigue strength of structures. Several methods ... -
Local strain energy based fatigue assessment of cruciform welded joints: experimental data analysis and influence of hot-dip galvanization
Viespoli, Luigi Mario; Mutignani, Francesco; gulyas, gabor; remes, heikki; Berto, Filippo (Journal article; Peer reviewed, 2018)Performing the fatigue assessment of a welded joint using the Notch Stress Intensity Factors [1] presents two major challenges. The first is the necessity of a precise reconstruction of the stress field around the notch ... -
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 ... -
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 ... -
Mechanical characterization of lead alloys for subsea high voltage power cable applications
Viespoli, Luigi Mario (Doctoral theses at NTNU;2020:301, Doctoral thesis, 2020)Subsea power cables are an important component in electrical grids, connecting both offshore facilities to the mainland and interconnecting countries through sea stretches, for lengths up to hundreds of kilometres. Such ... -
Medium to high cycle fatigue investigation on hot dip galvanized structural steel welded joints
Viespoli, Luigi Mario; Mutignani, Francesco; Berto, Filippo (Journal article; Peer reviewed, 2019)Hot dip galvanization offers stable and lasting corrosion protection to steel structure, both acting as a barrier for external agents and inducing galvanic protection, through the deposition of a thin layer of zinc on the ... -
Rapid extrapolation of high temperature low-cycle fatigue curves for a nickel superalloy
Viespoli, Luigi Mario; Berto, Filippo (Journal article; Peer reviewed, 2019)In many industrial applications, ranging from the energy, the aviation to the microelectronics field, metallic alloys are subjected to fatigue load at elevated temperatures. The detrimental influence of temperature and ... -
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 ... -
Strain controlled medium cycle fatigue of a notched Pb-Sn-Cd lead alloy
Viespoli, Luigi Mario; Johanson, Audun; Alvaro, Antonio; Nyhus, Bård; Berto, Filippo (Journal article; Peer reviewed, 2019)During the extrusion process of subsea power cable sheathing layer it is possible that metallic and/or non-metallic debris present in the processing environment enter the metal lattice originating discontinuities that might ... -
Subsea power cable sheathing: an investigation of lead fatigue performance
Viespoli, Luigi Mario; Johanson, Audun; Alvaro, Antonio; Nyhus, Bård; Berto, Filippo (Peer reviewed; Journal article, 2020)The protection of subsea power cables against electrical failure is achieved by the use of a watertight layer. Due to its properties of chemical stability and ductility, lead has been the material of choice for this purpose ... -
Tape winding angle influence on subsea cable sheathing fatigue performance
Viespoli, Luigi Mario; Panza, Luigi; Johanson, Audun; Alvaro, Antonio; Soma, Aurelio; Berto, Filippo (Peer reviewed; Journal article, 2020)A fundamental component of subsea power cables is the thin galvanized steel tape winded around the dielectric and sheathing layer in order to prevent permanent thermal cycling induced deformation. The pressure state induced ... -
Tensile and fatigue behavior of a Pb-Sn-Sb alloy investigated via small-scale in-situ mechanical testing in SEM
Wan, Di; Viespoli, Luigi Mario; Johanson, Audun; Hagen, Anette Brocks; Berto, Filippo; Alvaro, Antonio (Peer reviewed; Journal article, 2020)Pb-Sn-Sb alloys (E-alloy) are commonly used in subsea power cable sheathing. Due to the relatively low melting temperature, i.e. around 600 K, this type of alloy is prone to experience microstructural time-dependent evolution ...