Pages
- 1
- 2
- document
- Krielaart, G.P. (author), Sietsma, J. (author), Van der Zwaag, S. (author) journal article 1997
- document
-
Tirumalasetty, G.K. (author), Van Huis, M.A. (author), Fang, C.M. (author), Xu, Q. (author), Tichelaar, F.D. (author), Hanlon, D.N. (author), Sietsma, J. (author), Zandbergen, H.W. (author)Multiphase steels utilising composite strengthening may be further strengthened via grain refinement or precipitation by the addition of microalloying elements. In this study a Nb microalloyed steel comprising martensite, bainite and retained austenite has been studied. By means of transmission electron microscopy (TEM), we have investigated the...journal article 2011
- document
-
Tirumalasetty, G.K. (author), Van Huis, M.A. (author), Kwakernaak, C. (author), Sietsma, J. (author), Sloof, W.G. (author), Zandbergen, H.W. (author)Uniaxial straining experiments were performed on a rolled and annealed Si-alloyed TRIP (transformation-induced plasticity) steel sheet in order to assess the role of its microstructure on the mechanical stability of austenite grains with respect to martensitic transformation. The transformation behavior of individual metastable austenite grains...journal article 2012
- document
-
Tirumalasetty, G.K. (author), Fang, C.M. (author), Xu, Q. (author), Jansen, J. (author), Sietsma, J. (author), Van Huis, M.A. (author), Zandbergen, H.W. (author)A transmission electron microscopy study was conducted on nanoprecipitates formed in Ti microalloyed transformation-inducedplasticity-assisted steels, revealing the presence of Ti(N), Ti2CS and a novel type of ultra-fine Fe(C) precipitate. The matrix/precipitate orientation relationships, sizes and shapes were investigated in detail. The...journal article 2012
- document
-
Tirumalasetty, G.K. (author), Van Huis, M.A. (author), Kwakernaak, C. (author), Sietsma, J. (author), Sloof, W.G. (author), Zandbergen, H.W. (author)A combination of Electron Back-Scattered Diffraction (EBSD) and high-sensitivity Electron Probe Micro-Analysis (EPMA) was used to correlate the changes in microstructural features upon deformation with local chemical composition in Transformation-Induced Plasticity steels. A novel cleaning procedure was developed that allows complete monitoring...journal article 2013
- document
-
Tirumalasetty, G.K. (author), Fang, C.M. (author), Jansen, J. (author), Yokosawa, T. (author), Boeije, M.J.F. (author), Sietsma, J. (author), Van Huis, M.A. (author), Zandbergen, H.W. (author)Chromium (Cr), Manganese (Mn), and Carbon (C) are well known alloying elements used in technologically important alloy steels and advanced high strength steels. It is known that binary CrCx and MnCx carbides can be formed in steels, but in this study we reveal for the first time that Cr and Mn were found combined in novel ternary cementite type ...journal article 2014
- document
-
Navarro Lopez, A. (author), Hidalgo Garcia, J. (author), Sietsma, J. (author), Santofimia, Maria Jesus (author)The accelerated formation of bainite in presence of martensite is opening a new processing window for the steel industry. However, for a feasible industrial implementation, it is necessary to determine the mechanical behaviour of the steels developed under such conditions. This study focuses on analysing the effects of the formation of...journal article 2018
- document
-
Celada-Casero, Carola (author), Sietsma, J. (author), Santofimia, Maria Jesus (author)There is sufficient experimental evidence to propose that the formation kinetics of athermal martensite directly depends on the austenite grain structure from which the martensite forms. Yet, this dependence is frequently ignored. The present study investigates the role of the prior austenite grain size (PAGS) in the martensitic...journal article 2019
- document
-
Ayenampudi, S. (author), Celada-Casero, Carola (author), Sietsma, J. (author), Santofimia, Maria Jesus (author)Medium-Mn Quenching & Partitioning (Q&P) steels have been recently considered as potential candidates for the 3rd generation advanced high-strength steels. The processing of these steels aims to induce the partitioning of substitutional alloying elements from martensite to austenite during an isothermal treatment at high temperature,...journal article 2019
- document
-
Hajizad, O. (author), Kumar, A. (author), Li, Z. (author), Petrov, R.H. (author), Sietsma, J. (author), Dollevoet, R.P.B.J. (author)Wheel–rail contact creates high stresses in both rails and wheels, which can lead to different damage, such as plastic deformation, wear and rolling contact fatigue (RCF). It is important to use high-quality steels that are resistant to these damages. Mechanical properties and failure of steels are determined by various microstructural...journal article 2019
- document
-
Kumar, A. (author), Agarwal, G. (author), Petrov, R.H. (author), Goto, S. (author), Sietsma, J. (author), Herbig, M. (author)The formation of White (WEL) and Brown Etching Layers (BEL) on rail raceways during service causes the initiation of microcracks which finally leads to failure. Detailed characterization of the WEL and the BEL in a pearlitic rail steel is carried out from micrometer to atomic scale to understand their microstructural evolution. A...journal article 2019
- document
-
Goulas, C. (author), Kumar, A. (author), Mecozzi, M.G. (author), Castro-Cerda, Felipe Manuel (author), Herbig, Michael (author), Petrov, R.H. (author), Sietsma, J. (author)Atomic-scale investigation was performed on 51CrV4 steel, isothermally held at different temperatures within the bainitic temperature range. Transmission electron microscopy (TEM) analysis revealed three different morphologies: lower, upper, and inverse bainite. Atom Probe Tomography (APT) analysis of lower bainite revealed cementite...journal article 2019
- document
-
Ioannidou, C. (author), Arechabaleta Guenechea, Z. (author), Navarro Lopez, A. (author), Rijkenberg, Arjan (author), Dalgliesh, Robert M. (author), Kölling, S. (author), Bliznuk, Vitaliy (author), Pappas, C. (author), Sietsma, J. (author), van Well, A.A. (author), Offerman, S.E. (author)The precipitation kinetics of vanadium carbides and its interaction with the austenite-to-ferrite phase transformation is studied in two micro-alloyed steels that differ in vanadium and carbon concentrations by a factor of two, but have the same vanadium-to-carbon atomic ratio of 1:1. Dilatometry is used for heat-treating the specimens and...journal article 2019
- document
-
Marques Pereira, V. (author), Schut, H. (author), Sietsma, J. (author)An approach to improve the performance of steels for fusion reactors is to reinforce them with oxide nanoparticles. These can hinder dislocation and grain boundary movement and trap radiation-induced defects, thus increasing creep and radiation damage resistance. The present work investigates the thermal stability of the microstructure and...journal article 2020
- document
-
Navarro Lopez, A. (author), Hidalgo Garcia, J. (author), Sietsma, J. (author), Santofimia, Maria Jesus (author)The initial formation of athermal martensite was proven to accelerate the subsequent bainite formation kinetics during isothermal holdings below the martensite-start temperature (M<sub>s</sub>). The presence of prior athermal martensite (PAM) within the phase mixture is expected to modify the overall mechanical response of these newly...journal article 2020
- document
-
Hidalgo Garcia, J. (author), Vittorietti, M. (author), Farahani, H. (author), Vercruysse, F. (author), Petrov, R.H. (author), Sietsma, J. (author)Understanding the local strain enhancement and lattice distortion resulting from different microstructure features in metal alloys is crucial in many engineering processes. The development of heterogeneous strain not only plays an important role in the work hardening of the material but also in other processes such as recrystallization and...journal article 2020
- document
-
Ioannidou, C. (author), Navarro Lopez, A. (author), Rijkenberg, Arjan (author), Dalgliesh, Robert M. (author), Koelling, Sebastian (author), Pappas, C. (author), Sietsma, J. (author), van Well, A.A. (author), Offerman, S.E. (author)In-situ Small-Angle Neutron Scattering (SANS) is used to determine the time evolution of the chemical composition of precipitates at 650 °C and 700 °C in three micro-alloyed steels with different vanadium (V) and carbon (C) concentrations. Precipitates with a distribution of substoichiometric carbon-to-metal ratios are measured in all steels....journal article 2020
- document
-
Yilmaz, A. (author), Ozkan, C. (author), Sietsma, J. (author), Gonzalez Garcia, Y. (author)The effect of ferrite-pearlite and ferrite-martensite phase combinations on the passive layer properties of low carbon steel is investigated in a 0.1 M NaOH solution. Heat treatments were designed to obtain ferrite-pearlite and ferrite-martensite microstructures with similar ferrite volume fractions. Potentiostatic polarisation and...journal article 2021
- document
-
Traka, K. (author), Sedighiani, K. (author), Bos, C. (author), Galan Lopez, J. (author), Angenendt, Katja (author), Raabe, Dierk (author), Sietsma, J. (author)A cellular automaton algorithm for curvature-driven coarsening is applied to a cold-rolled interstitial-free steel's microstructure - obtained through electron backscatter diffraction (EBSD). Recrystallization nucleation occurs naturally during the simulation, due to the highly heterogeneous and hence competitive growth among pre-existing ...journal article 2021
- document
-
Koopmans, T.T.W. (author), Sietsma, J. (author), Zhao, L. (author), Santofimia, Maria Jesus (author)The quenching and partitioning (Q&P) process is a heat treatment process, aiming at the creation of steel microstructures composed of martensite and retained austenite. Herein, the thermal stability of the microstructure is investigated upon reheating steel microstructures, created with different Q&P settings, in different thermal...journal article 2021
Pages
- 1
- 2