Blar i NTNU Open på forfatter "Holmedal, Bjørn"
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Influence of thermomechanical processing sequence on properties of AA6082-IF steel cold roll bonded composite sheet
Arbo, Siri Marthe; Bergh, Tina; Solhaug, Harald; Westermann, Ida; Holmedal, Bjørn (Journal article; Peer reviewed, 2018)Cold roll bonded tri-layered composites consisting of AA6082 and IF steel have been produced. The goal was to find the optimal sequence of solutionizing, aging and rolling, for obtaining good bond strength and at the same ... -
Investigation of a Non-Associated Flow Rule Incorporating Corner Effects and Comparison with an Elastoplastic Crystal Plasticity Model
Gjesdal, Bjørnar (Master thesis, 2019)Den konvensjonelle assosierte flyteregelen, brukt i kontinuums plastisitetsmodeller, er uegnet til prediksjon av flytinstabiliteter i tynne plater under biaksiell last og plastisk bukling ved bifurkasjonsanalyse. Teorien ... -
Investigation of bond strength and intermetallic phases in roll bonded steel-aluminium laminates at 150oC - Including the use of nickel interlayers
Sverdrup, Erlend (Master thesis, 2018)This master's thesis investigates intermetallic growth and metallurgical bonding in cold roll-bonded steel-aluminium laminates. Commercially pure AA1080 aluminium alloy have been roll-bonded with two different steel types, ... -
Layer continuity in accumulative roll bonding of dissimilar material combinations
Govindaraj, Nagaraj Vinayagam; Frydendahl, Jan Gaute; Holmedal, Bjørn (Journal article; Peer reviewed, 2013)Strips were made by accumulative roll bonding of up to 64 alternating layers of an AA3103 alloy and either commercial purity copper or CuZn20 brass as the second type of layer. With increasing number of accumulative roll ... -
Linking mechanical properties to precipitate microstructure in three Al-Mg-Si(-Cu) alloys
Sunde, Jonas Kristoffer; Lu, Feng; Marioara, Calin Daniel; Holmedal, Bjørn; Holmestad, Randi (Peer reviewed; Journal article, 2021)The mechanical properties of age hardenable Al alloys depend strongly on the precipitate microstructure. This work has investigated the relationship between properties such as strength and ductility and the distribution ... -
Low Cycle Fatigue of Extruded and Cast Aluminium Alloy 6082
Reinton, Tone Elise (Master thesis, 2017)The objective of the research is to determine the differences between the low cycle fatigue properties of an extruded and cast treatments of AA6082-T6 used as the forging billet in the production of a car suspension arm. ... -
A machine learning enabled ultra-fine grain design strategy of Mg–Mn-based alloys
Mi, Xiaoxi; Jing, Xuerui; Wang, Hailian; Xu, Jianbin; She, Jia; Tang, Aitao; Holmedal, Bjørn; Pan, Fusheng (Peer reviewed; Journal article, 2023)Grain size is the critical characteristic of ultra-fine grain Magnesium (Mg), which is a concrete representation of the whole heat deformation procedure. In this paper, a design strategy was proposed to quantitatively ... -
The microstructural origin of a hardness double-peak in an age-hardened EN-AW 6082
Hell, Christoph Martin; Holmedal, Bjørn; Bjørge, Ruben; Marioara, Calin Daniel; Holmestad, Randi (Peer reviewed; Journal article, 2023)In this study, the origin of a double-peak during artificial aging of an EN-AW 6082 is analyzed with (S)TEM. The acquired TEM data is used as an input into a strength model by Holmedal [1] to explore the origin of the ... -
Modeling over-ageing in Al-Mg-Si alloys by a multi-phase CALPHAD-coupled Kampmann-Wagner Numerical model
Du, Qiang; Tang, Kai; Marioara, Calin Daniel; Andersen, Sigmund Jarle; Holmedal, Bjørn; Holmestad, Randi (Journal article, 2017)The formation of the equilibrium precipitation phase during ageing treatment of Al-Mg-Si alloys is preceded by a series of metastable phases. Given longer ageing time, higher ageing temperature or elevated temperature ... -
Modeling strain-path changes in aluminum and steel
Qin, Jisheng; Holmedal, Bjørn; Zhang, Kai; Hopperstad, Odd Sture (Journal article, 2017)The present paper evaluates two phenomenological plasticity models which account for the influence of strain-path change (SPC) on the stress-strain behavior. The HAH model (Barlat et al., 2014) is modified to capture SPC ... -
Modelling and experimental validation of microstructure evolution during the cooling stage of homogenization heat treatment of Al-Mg-Si alloys
Du, Qiang; Jia, Lina; Tang, Kai; Holmedal, Bjørn (Journal article; Peer reviewed, 2018)A CALPHAD-coupled multi-component multi-phase Kampmann–Wagner Numerical modelling framework has been adapted and coupled with a homogenization model to predict the competitive nucleation and growth of multi-sized ... -
Modelling of strain-path transients in commercially pure aluminium
Qin, Jisheng; Holmedal, Bjørn; Hopperstad, Odd Sture (Journal article, 2017)In the current work, the recently proposed homogeneous anisotropic hardening (HAH) model, featuring a distorted yield surface, is applied to commercially pure aluminium. A dislocation-based hardening rule is incorporated ... -
Modelling work hardening of aluminium alloys containing dispersoids
Zhao, Qinglong; Holmedal, Bjørn (Journal article; Peer reviewed, 2013)The influence of dispersoids on tensile deformation behaviour has been studied by comparison of aluminium alloys containing different dispersoid densities. It was found that a fine dispersion of non-shearable particles led ... -
Multi-level modelling of mechanical anisotropy of commercial pure aluminium plate: Crystal plasticity models, advanced yield functions and parameter identification
Zhang, Kai; Holmedal, Bjørn; Hopperstad, Odd Sture; Dumoulin, Stephane; Gawad, Jerzy; Van Bael, Albert; Van Houtte, P (Journal article; Peer reviewed, 2015)The mechanical anisotropy of an AA1050 aluminium plate is studied by the use of five crystal plasticity models and two advanced yield functions. In-plane uniaxial tension properties of the plate were predicted by the ... -
Nano-scale characterisation of sheared β” precipitates in a deformed Al-Mg-Si alloy
Christiansen, Emil; Marioara, Calin Daniel; Holmedal, Bjørn; Hopperstad, Odd Sture; Holmestad, Randi (Journal article; Peer reviewed, 2019)This paper compares the nano-scale structure of β” precipitates in a peak-aged Al-Mg-Si alloy before and after deformation. Three complementary advanced transmission electron microscopy techniques are used to reveal the ... -
On the influence of crystallographic texture on cyclic hardening of an AlMgSi alloy
Akash, Gopal; Shah, Sohail; Holmedal, Bjørn (Peer reviewed; Journal article, 2024)The influence of crystallographic texture on hardening achieved by cyclic loading at room temperature, was tested by comparing samples from an axisymmetric round bar and a flat profile, both made of non-recrystallized, ... -
On the spatio-temporal characteristics of the Portevin-Le Chatelier effect in aluminium alloy AA5182: An experimental and numerical study
Xu, Jianbin; Hopperstad, Odd Sture; Holmedal, Bjørn; Berstad, Torodd; Manik, Tomas; Marthinsen, Knut (Peer reviewed; Journal article, 2023)The Portevin–Le Chatelier (PLC) effect and its spatio-temporal characteristics in the aluminium alloy AA5182 are studied experimentally and numerically in the current work. An extremely high-frequency camera (up to 1000 ... -
On the Use of a Cluster Identification Method and a Statistical Approach for Analyzing Atom Probe Tomography Data for GP Zones in Al–Zn–Mg(–Cu) Alloys
Shah, Sohail; Thronsen, Elisabeth; de gauser, Frederic; hatzoglou, constantinos; Marioara, Calin Daniel; Holmestad, Randi; Holmedal, Bjørn (Peer reviewed; Journal article, 2023)Early-stage clustering in two Al–Mg–Zn(–Cu) alloys has been investigated using atom probe tomography and transmission electron microscopy. Cluster identification by the isoposition method and a statistical approach based ... -
Permanent Effect of a Cryogenic Spill on Fracture Properties of Carbon Steel
Keseler, Hanne (Master thesis, 2015)In this work, the permanent effect of a cryogenic spill on the fracture properties of carbon steel was investigated. The experimental work consisted of two main parts. The first part was the examination of a plate of ... -
Permanent effect of a cryogenic spill on fracture properties of structural steels
Keseler, Hanne; Westermann, Ida; Kandukuri, Sastry Yagnanna; Nøkleby, John Olav; Holmedal, Bjørn (Journal article; Peer reviewed, 2015)Fracture analysis of a standard construction steel platform deck, which had been exposed to a liquid nitrogen spill, showed that the brittle fracture started at a flaw in the weld as a consequence of low-temperature ...