- document
-
Kuś, G.I. (author), van der Zwaag, S. (author), Bessa, M.A. (author)Gaussian processes are well-established Bayesian machine learning algorithms with significant merits, despite a strong limitation: lack of scalability. Clever solutions address this issue by inducing sparsity through low-rank approximations, often based on the Nystrom method. Here, we propose a different method to achieve better scalability...journal article 2021
- document
-
Montano, V. (author), Urban, Marek W. (author), van der Zwaag, S. (author), Garcia, Santiago J. (author)Autonomous through-thickness scratch repair (healing) in coatings requires scratch closure and interfacial molecular sealing. Although qualitative aspects of the first stage of self-healing have been addressed, quantitative description enabling the control over the healing process need further understanding. In this work the polymer-architecture...journal article 2022
- document
-
Hedayati, R. (author), Güven, Aysun (author), van der Zwaag, S. (author)Materials with a negative Poisson's ratio, also known as auxetics, have attracted a lot attention as they have shown innovation potential in applications for energy damping, modern fasteners, biomedical implants, piezoelectric sensors, and soft actuators. In this study, we introduce different patterns of graded distribution of unit cells with...journal article 2021
- document
-
Tuluk, A. (author), Brouwer, J.C. (author), van der Zwaag, S. (author)BiFeO <sub>3</sub> is a multiferroic material with a perovskite structure that has a lot of potential for use in sensors and transducers. However, obtaining pure single-phase BiFeO <sub>3</sub> ceramic with a low electrical conductivity via solid-state reactions remains a problem that limits its application. In this work, the suppression of...journal article 2022
- document
-
De Breuker, R. (author), Mkhoyan, T. (author), Nazeer, N. (author), Stuber, V.L. (author), Wang, Xuerui (author), Mkhoyan, A. (author), Groves, R.M. (author), van der Zwaag, S. (author), Sodja, J. (author)This article describes the challenges of integrating smart sensing, actuation, and control concepts into an over-sensed and over-actuated technology integrator. This technology integrator has more control inputs than the expected responses or outputs (over-actuated), and its every state is measured using more than one sensor system (over-sensed)...journal article 2022
- document
-
Tuluk, A. (author), Mahon, T.R. (author), van der Zwaag, S. (author), Groen, W.A. (author)BiFeO<sub>3</sub> is an interesting multiferroic material with potential use in sensors and transducers. However, the high coercive field and low dielectric strength of this material make the poling process extremely difficult. Poling becomes a lot easier if the ceramic particles are incorporated in a non-conductive polymer with comparable...journal article 2021
- document
-
Zhu, Jianing (author), Luo, Haiwen (author), Yang, Zhigang (author), Zhang, Chi (author), van der Zwaag, S. (author), Chen, H. (author)Kinetics of the austenite (γ) to ferrite (α) transformation and the reverse ferrite (α) to austenite (γ) transformation in a series of Fe-X (X = Ni, Mn and Co) binary alloys has been experimentally and theoretically investigated. A transition from partitioning to partitionless transformation has been predicted to occur during both the γ→α and...journal article 2017
- document
-
Shaji Karapuzha, A. (author), Kunnamkuzhakkal James, N. (author), Khanbareh, H. (author), van der Zwaag, S. (author), Groen, W.A. (author)The effects of Zr/Ti ratio on the dielectric and piezoelectric properties of the sintered Pb(Zr<sub>x</sub>Ti<sub>(1−x)</sub>)<sub>0.99</sub>Nb<sub>0.01</sub>O<sub>3</sub> piezoelectric ceramics across the entire range of phase diagram of the PZT solid solution was studied systematically. The materials were prepared by the conventional mixed...journal article 2016
- document
-
Mahon, T.R. (author), Giannopoulos, D. (author), van der Zwaag, S. (author), Groen, W.A. (author)In this work, we present the impact of using Na<sub>2</sub>CO<sub>3</sub> as a sintering aid and grain growth agent on the crystal structure, microstructure, and piezoelectric properties of (Bi<sub>0.5</sub>Na<sub>0.5</sub>)TiO<sub>3</sub> ceramics. The addition of Na<sub>2</sub>CO<sub>3</sub> leads to a substantial increase in the grain size...journal article 2021
- document
-
Tuluk, A. (author), Joshi, Siddharth (author), Mahon, T.R. (author), van der Zwaag, S. (author)Bismuth ferrite is a potentially interesting lead-free piezoelectric material for use in high-temperature applications due to its high Curie temperature. However, the high coercive field and high leakage currents of pure BiFeO3 (BFO) prevent reaching its theoretical performance level. The classic approach to tailoring piezoceramic properties...journal article 2022
- document
-
Giannopoulos, D. (author), Chen, Yu Chen (author), van der Zwaag, S. (author), Groen, W.A. (author)Piezoelectric transducers which rely on oscillating cantilever-type beams to harvest mechanical energy locally available in environments have been of great interest as a substitute for batteries. Most of the research efforts focus mostly on designs which aim at resonance matching to achieve maximum energy output without taking the mechanical...journal article 2021
- document
-
Wiessner, Manfred (author), Angerer, Paul (author), van der Zwaag, S. (author), Gamsjäger, Ernst (author)We describe the analysis of in-situ HT-XRD data of a dual phase stainless steel exposed to a complex thermal cycle of heating, holding and cooling. For the conditions used only low quality diffraction data could be collected. Peak positions, peak areas and peak broadening are modeled by the Rietveld method. The low signal-to noise ratio and...journal article 2021
- document
-
Tuluk, A. (author), van der Zwaag, S. (author)In this work, we investigated the piezoelectric properties of BiFeO3-rich (1 − (y + x)) BiFeO3–y PbTiO3–x SrTiO3 (0.1 ≤ x ≤ 0.35; 0.1 ≤ y ≤ 0.3) bulk piezoceramics, as this system could potentially lead to the development of bulk piezoelectric ceramics that are suitable for high-temperature applications (>200 °C). Samples with various levels...journal article 2023
- document
-
Yu, H. (author), Xu, W. (author), van der Zwaag, S. (author)The high performance of Ni single crystal superalloys during high temperature low stress creep service, is intrinsically determined by the combined effects of microstructural evolution and the dislocation behaviour. In the field of the evolution of dislocation network, two main recovery mechanism based on dislocation migration dominate the...journal article 2020
- document
-
Fu, Y. (author), Kwakernaak, C. (author), Brouwer, J.C. (author), Sloof, W.G. (author), Brück, E.H. (author), van der Zwaag, S. (author), van Dijk, N.H. (author)Abstract: The precipitation of supersaturated solutes at free surfaces in ternary Fe–3Au–4W and binary Fe–3Au and Fe–4W alloys (composition in weight percentage) for different ageing times was investigated at a temperature of 700 °C. The time evolution of the surface precipitation is compared among the three alloys to investigate the...journal article 2020
- document
-
Lan, H. (author), Tang, S. (author), DU, Linxiu (author), LI, Jianping (author), van der Zwaag, S. (author)The combined effects of the initial microstructure and heating rate on ferrite recrystallization, austenite formation and transformation kinetics of a regular ferrite-martensite dual phase steel are investigated. Special attention is given to the effect of the martensite distribution on mechanical properties, particularly the bendability....journal article 2021
- document
-
Chai, Zhisong (author), Hu, Jun (author), Wang, Chenchong (author), Wang, Lingyu (author), Sun, Weihua (author), van der Zwaag, S. (author), Xu, W. (author)Herein, the effect of Nb content on the phase transformation kinetics, microstructure, and mechanical properties of hot-rolled quenching and partitioning (Q&P) steel is investigated. The characteristics of three C–Mn–Si–Ti steels (0.18C, 2.0Si, 2.6Mn, and 0.015Ti) containing 0, 0.027, or 0.061 wt% Nb are compared. Results reveal that...journal article 2021
- document
-
Fang, H. (author), van der Zwaag, S. (author), van Dijk, N.H. (author)A computational 3D model that accounts for both nucleation and interface migration is a very useful tool to monitor and grasp the complexity of microstructure formation in low-alloyed steels. In the present study we have developed a 3D mixed-mode multigrain model for the austenite-ferrite and the austenite-ferrite-austenite formation capable...journal article 2021
- document
-
Du, Haiquan (author), Zhang, Shasha (author), Zhang, Bingyi (author), Tao, Xuewei (author), Yao, Zhengjun (author), Belov, Nikolay (author), van der Zwaag, S. (author), Liu, Zili (author)Al-Mg alloys are normally prone to lose part of their yield and tensile strength at high temperatures due to insufficient thermal stability of the microstructure. Here, we present a Ca-modified Al–Mg–Sc alloy demonstrating high strength at elevated temperatures. The microstructure contains Al<sub>4</sub>Ca phases distributed as a network...journal article 2021
- document
-
Dong, Haokai (author), Chen, Hao (author), Riyahi khorasgani, Ahmadreza (author), Zhang, Boning (author), Zhang, Yongjie (author), Wang, Zhenqiang (author), Zhou, Xiaosheng (author), Wang, Wei (author), van der Zwaag, S. (author)Mo is widely used as an effective microalloying element to improve mechanical performance of interphase precipitation steels, but the precise role of Mo in interphase precipitation behavior is not fully understood. In this contribution, interphase precipitation behavior in a series of Ti-Mo-bearing low carbon steels is systematically studied,...journal article 2022