- 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
- document
-
Cai, H. (author), Savenije, H.H.G. (author), Jiang, C. (author), Zhao, L. (author), Yang, Q. (author)The mean water level in estuaries rises in the landward direction due to a combination of the density gradient, the tidal asymmetry, and the backwater effect. This phenomenon is more prominent under an increase of the fresh water discharge, which strongly intensifies both the tidal asymmetry and the backwater effect. However, the interactions...journal article 2016
- document
-
Bojack, A. (author), Zhao, L. (author), Morris, P.F. (author), Sietsma, J. (author)The influence of austenitization treatment of a 13Cr6Ni2Mo supermartensitic stainless steel (X2CrNiMoV13-5-2) on austenite formation during reheating and on the fraction of austenite retained after tempering treatment is measured and analyzed. The results show the formation of austenite in two stages. This is probably due to inhomogeneous...journal article 2016
- document
-
We investigated the rotation of non-spherical particles (rod-like and disk-like) in turbulent channel flow with focus on inertial effects. A direct numerical simulation (DNS) with an Eulerian-Lagrangian approach was performed. A wide range of particle aspect ratios, λ, ranging from 0.01 to 50 were considered for Stokes numbers St equal to 1 and...conference paper 2015
- document
-
A suspension of oblate spheroidal (disk-like) particles in turbulent channel flow has been investigated with focus on the translational and rotational particle statistics. The effects of particle aspect ratio and inertia have been explored. The disk-like particles exhibited a significant preferential orientation in the plane of the mean shear....conference paper 2015
- document
-
Blondé, R.J.P. (author), Jimenez-Melero, E. (author), Huizenga, R.M. (author), Zhao, L. (author), Wright, J. (author), Brück, E.H. (author), Van der Zwaag, S. (author), Van Dijk, N.H. (author)The martensitic transformation behaviour of the metastable austenite phase in low-alloyed transformation-induced plasticity (TRIP) steels has been studied in situ using high-energy X-ray diffraction during deformation. The austenite stability during tensile deformation has been evaluated at different length scales. A powder diffraction analysis...journal article 2014
- document
-
Blondé, R.J.P. (author), Jimenez-Melero, E. (author), Anusuya Ponnusami, S. (author), Zhao, L. (author), Schell, N. (author), Brück, E.H. (author), Van der Zwaag, S. (author), Van Dijk, N.H. (author)While earlier studies on transformation-induced-plasticity (TRIP) steels focused on the determination of the austenite-to-martensite decomposition in uniform deformation or thermal fields, the current research focuses on the determination of the local retained austenite-to-martensite transformation behaviour in an inhomogeneous yet carefully...journal article 2014
- document
-
Zhao, L. (author), Andersson, H.I. (author), Gillissen, J.J.J. (author)Transfer of mechanical energy between solid spherical particles and a Newtonian carrier fluid has been explored in two-way coupled direct numerical simulations of turbulent channel flow. The inertial particles have been treated as individual point particles in a Lagrangian framework and their feedback on the fluid phase has been incorporated in...journal article 2013
- document
-
Van Tol, R.T. (author), Zhao, L. (author), Schut, H. (author), Sietsma, J. (author)The effect of strain on the deformation mechanisms in an austenitic Mn-based twinning induced plasticity (TWIP) steel is investigated using magnetic measurements, XRD, positron beam Doppler spectroscopy, and finite element method simulations. The experimental observations reveal the formation of a0-martensite at specific degrees of deformation,...journal article 2012
- document
-
Dung, N.H. (author), Zhang, L. (author), Ou, Z.Q. (author), Zhao, L. (author), Van Eijck, L. (author), Mulders, A.M. (author), Avdeev, M. (author), Suard, E. (author), Van Dijk, N.H. (author), Brück, E. (author)Using high-resolution neutron diffraction measurements for Mn-rich hexagonal Mn-Fe-P-Si compounds, we show that the substitution of Mn for Fe on the 3f sites results in a linear decrease of the Fe/Mn(3f) magnetic moments, while the Mn(3g) magnetic moments remain constant. With increasing temperature, the Mn(3g) magnetic moments show almost no...journal article 2012
- document
-
Van Tol, R.T. (author), Kim, J.K. (author), Zhao, L. (author), Sietsma, J. (author), De Cooman, B.C. (author)To understand the formation of ?'-martensite in high stacking fault energy twinning-induced plasticity steel deformed in the deep drawing mode, the existing phases were investigated using magnetic and transmission electron microscopy (TEM). Small fractions of ?'-martensite were quantitatively determined by magnetization saturation experiments...journal article 2012
- document
-
Santofimia, M.J. (author), Zhao, L. (author), Sietsma, J. (author)The application of the quenching and partitioning (Q&P) process in steels involves a microstructural evolution that is more complex than just the formation of martensite followed by carbon partitioning from martensite to austenite. Examples of this complexity are the formation of epitaxial ferrite during the first quenching step and the...journal article 2011
- document
-
Zhao, L. (author)In this thesis, we present an automatic polyp detection approach that integrates knowledge from flow visualization techniques. Our primary goal was to compute additional characteristic polyp features that improve the CAD performance of existing polyp detection approaches by eliminating found false-positive polyp candidates. We found that surface...doctoral thesis 2011
- document
-
Santofimia, Maria Jesus (author), Zhao, L. (author), Petrov, R.H. (author), Kwakernaak, C. (author), Sloof, W.G. (author), Sietsma, J. (author)This paper presents a detailed characterization of the microstructural development of a new quenching and partitioning (Q&P) steel. Q&P treatments, starting from full austenitization, were applied to the developed steel, leading to microstructures containing volume fractions of retained austenite of up to 0.15. The austenite was...journal article 2011
- document
-
Amirthalingam, M. (author), Hermans, M.J.M. (author), Zhao, L. (author), Richardson, I.M. (author)A quantitative analysis of retained austenite and nonmetallic inclusions in gas tungsten arc (GTA)–welded aluminum-containing transformation-induced-plasticity (TRIP) steels is presented. The amount of retained austenite in the heat-affected and fusion zones of welded aluminum-containing TRIP steel with different base metal austenite fractions...journal article 2009
- document
-
Santofimia, Maria Jesus (author), Speer, JG (author), Clarke, AJ (author), Zhao, L. (author), Sietsma, J. (author)The quenching and partitioning (Q&P) process is a new heat treatment for the creation of advanced high-strength steels. This treatment consists of an initial partial or full austenitization, followed by a quench to form a controlled amount of martensite and an annealing step to partition carbon atoms from the martensite to the austenite. In...journal article 2009
- document
-
Santofimia, M.J. (author), Zhao, L. (author), Sietsma, J. (author)The “quenching and partitioning” (Q&P) process has been studied in a low-carbon steel containing 1.1 wt pct aluminum by heat treatments consisting of partial austenitization at 900 °C and subsequent rapid cooling to a quenching temperature in the range between 125 °C and 175 °C, followed by an isothermal treatment (partitioning step) at 250 °C...journal article 2008
- document
-
Zhao, L. (author), Botha, C.P. (author), Truyen, R. (author), Vos, F.M. (author), Post, F.H. (author)Many computer aided diagnosis (CAD) schemes have been developed for colon cancer detection using Virtual Colonoscopy (VC). In earlier work, we developed an automatic polyp detection method integrating flow visualization techniques, that forms part of the CAD functionality of an existing Virtual Colonoscopy pipeline. Curvature streamlines were...conference paper 2008
- document
-
Luzginova, N.V. (author), Zhao, L. (author), Sietsma, J. (author)The cementite spheroidization process is investigated in hypereutectoid steels with different chromium (Cr) contents. A spheroidized structure in high-carbon steel is usually obtained by a divorced eutectoid transformation (DET) reaction, which occurs during slow cooling of austenite with fine cementite particles. A bimodal distribution of...journal article 2008