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Yongho Sohn - One of the best experts on this subject based on the ideXlab platform.
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composition dependent Interdiffusion Coefficient reduced elastic modulus and hardness in γ γ and β phases in the ni al system
Journal of Alloys and Compounds, 2017Co-Authors: Le Zhou, Abhishek Mehta, Kyu Cho, Yongho SohnAbstract:Abstract A combinatorial approach using diffusion couples and advanced characterization was carried out to investigate the composition-dependent Interdiffusion and mechanical properties of γ-Ni(Al) solid solution, γ′-Ni3Al and β-NiAl. The diffusion couples between pure Ni and Ni52Al48 were annealed at temperatures of 1000 °C, 1100 °C and 1200 °C for 96 h, 48 h and 24 h, respectively. The γ-Ni(Al), γ′-Ni3Al and β-NiAl have developed in the diffusion zone. The β-NiAl transformed to martensite above room temperature when Al is less than 37 at.%. The composition-dependent Interdiffusion Coefficients for all phases corresponded closely to previous research. A systematic composition-dependent elastic modulus and hardness for γ-Ni(Al), γ′-Ni3Al and β-NiAl phases were obtained by nanoindentation. Variation of elastic modulus and hardness in the γ-Ni(Al) solid solution is influenced by solid solution strengthening and hardening due to precipitation of γ′-Ni3Al while cooling. The evolution of elastic modulus and hardness in the β-NiAl phase exhibited a minimum value of elastic modulus and hardness near the phase boundary between martensite and austenite. Lattice softening associated with martensitic transformation was recognized to lower the value of elastic modulus and hardness.
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Interdiffusion and impurity diffusion in polycrystalline mg solid solution with al or zn
Journal of Alloys and Compounds, 2014Co-Authors: Catherine Kammerer, Nagraj S Kulkarni, R J Warmack, Yongho SohnAbstract:Abstract Interdiffusion and impurity diffusion in Mg binary solid solutions, Mg(Al) and Mg(Zn) were investigated at temperatures ranging from 623 to 723 K. Interdiffusion Coefficients were determined via the Boltzmann–Matano Method using solid-to-solid diffusion couples assembled with polycrystalline Mg and Mg(Al) or Mg(Zn) solid solutions. In addition, the Hall method was employed to extrapolate the impurity diffusion Coefficients of Al and Zn in pure polycrystalline Mg. For all diffusion couples, electron microprobe analysis was utilized for the measurement of concentration profiles. The Interdiffusion Coefficient in Mg(Zn) was higher than that of Mg(Al) by an order of magnitude. Additionally, the Interdiffusion Coefficient increased significantly as a function of Al content in Mg(Al) solid solution, but very little with Zn content in Mg(Zn) solid solution. The activation energy and pre-exponential factor for the average effective Interdiffusion Coefficient in Mg(Al) solid solution were determined to be 186.8 (±0.9) kJ/mol and 7.69 × 10−1 (±1.80 × 10−1) m2/s, respectively, while those determined for Mg(Zn) solid solution were 139.5 (±4.0) kJ/mol and 1.48 × 10−3 (±1.13 × 10−3) m2/s. In Mg, the Zn impurity diffusion Coefficient was an order of magnitude higher than the Al impurity diffusion Coefficient. The activation energy and pre-exponential factor for diffusion of Al impurity in Mg were determined to be 139.3 (±14.8) kJ/mol and 6.25 × 10−5 (±5.37 × 10−4) m2/s, respectively, while those for diffusion of Zn impurity in Mg were determined to be 118.6 (±6.3) kJ/mol and 2.90 × 10−5 (±4.41 × 10−5) m2/s.
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simultaneous tracer diffusion and Interdiffusion in a sandwich type configuration to provide the composition dependence of the tracer diffusion Coefficients
Philosophical Magazine, 2014Co-Authors: Irina V. Belova, Nagraj S Kulkarni, Yongho SohnAbstract:In this paper, a new formalism of a combined tracer and Interdiffusion experiment for a binary Interdiffusion couple is developed. The analysis requires an Interdiffusion couple that initially contains a thin layer of tracers of one or both of the constituent elements at the original interface of the couple (sandwich Interdiffusion experiment). This type of Interdiffusion experiment was first performed in 1958 by J.R. Manning. The theoretical analysis presented in this paper is based on a newly developed phenomenological theory of isotopic Interdiffusion combined with the Boltzmann–Matano formalism. This new analysis now provides the means to obtain the composition dependent Interdiffusion Coefficient and tracer diffusion Coefficients simultaneously from analysis of the Interdiffusion and tracer profiles in a single sandwich Interdiffusion experiment. The new analysis is successfully applied to the results of Manning’s original ‘sandwich Interdiffusion’ experiment in the Ag–Cd system (six couples in total...
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investigation of Interdiffusion behavior in the mo zr binary system via diffusion couple studies
International Journal of Refractory Metals & Hard Materials, 2014Co-Authors: A Paz E Y Puente, Dennis D Keiser, J Dickson, Yongho SohnAbstract:Abstract Zirconium has recently garnered attention for use as a diffusion barrier between U–Mo metallic nuclear fuels and Al alloy cladding. In order to gain a fundamental understanding of the diffusional interactions, the Interdiffusion behavior in the binary Mo–Zr system was investigated via solid-to-solid diffusion couples annealed in the temperature range of 750 to 1050 °C. A combination of scanning electron microscopy, X-ray energy dispersive spectroscopy, and electron probe microanalysis were used to examine the microstructure and concentration profiles across the Interdiffusion zone. A large β-Zr (cI2) solid solution layer and a thin (~ 1–2 μm) layer of Mo2Zr (cF24) developed in all couples. Parabolic growth constants and concentration dependent Interdiffusion Coefficients were calculated for the Mo2Zr and Zr solid solution phases, respectively. The pre-exponential factor and activation energy for growth of the Mo2Zr phase were determined to be approximately 6.5 × 10− 15 m2/s and 90 kJ/mol, respectively. The Interdiffusion Coefficient in β-Zr solid solution decreased with an increase in Mo concentration. Both the pre-exponential factors (2 × 10− 8 m2/s at 2 at.% Mo to near 5 × 10− 8 m2/s at 9 at.% Mo) and activation energies (140 kJ/mol at 2 at.% Mo to approximately 155 kJ/mol at 9 at.% Mo) of Interdiffusion Coefficients were determined to increase with an increase in Mo concentration.
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simultaneous measurement of tracer and Interdiffusion Coefficients an isotopic phenomenological diffusion formalism for the binary alloy
Philosophical Magazine, 2013Co-Authors: Irina V. Belova, Nagraj S Kulkarni, Yongho SohnAbstract:In this paper, a new development of the classic Onsager phenomenological formalism is derived using relations based on linear response theory. The development concerns the correct description of the fluxes of the atomic isotopes. The resulting expressions in the laboratory frame are surprisingly simple and consist of terms coming from the standard Interdiffusion expressions and from Fick’s first law, where the tracer diffusion Coefficient is involved thus providing a better understanding of the relationship between the two approaches – Fick’s first law and the Onsager phenomenological formalism. From an experimental application perspective, the new development is applied to the binary alloy case. The formalism provides the means to obtain the Interdiffusion Coefficient and tracer diffusion Coefficients simultaneously from analysis of the Interdiffusion composition profiles in a single experiment.
Cui Yuwen - One of the best experts on this subject based on the ideXlab platform.
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Diffusion research in HCP Mg–Al–Sn ternary alloys
'Elsevier BV', 2020Co-Authors: Zhou Zhengfei, Gu Yuanyu, Xu Guanglong, Guo Yanhua, Cui YuwenAbstract:Diffusion behavior in the HCP Mg–Al–Sn ternary alloys was experimentally investigated at 673 K and 723 K by analyzing solid-state diffusion couples. From the composition profiles analytically represented by error function expansion, the inter- and impurity diffusion Coefficients were extracted by the Whittle-Green and generalized Hall methods respectively, which enable to establish the diffusion properties of the HCP Mg–Al–Sn alloys. The present results, together with the binary diffusion data of Mg–Al and Mg–Sn binaries, reveal that the average value of the main Interdiffusion Coefficient ~DMgSnSn over the investigated compositions is 1.39 times larger than ~DMgAlAl at 673 K and 1.36 times at 723 K, respectively, implying Sn diffuses comparably faster than Al in the HCP Mg–Al–Sn alloys. The main Interdiffusion Coefficients ~DMgAlAl and ~DMgSnSn and the impurity diffusion Coefficient D*Sn(Mg-Al) increases with increasing the content of diffusing element, either Al or Sn, however, D*Al(Mg-Sn) increases first and then decreases as the Sn composition increases. The cross Interdiffusion Coefficients are scattering, their composition dependences are not very conclusive, however, a trend that ~DMgAlSn and ~DMgSnA become negligibly small or even negative was evidenced as the content of Al or Sn approaches 0.The authors would like to acknowledge National Natural Science Foundation of China (Grant No. 51571113), Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, and Priority Academic Program Development of Jiangsu Higher Education Institution (PAPD).Peer reviewe
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High-throughput extraction of the anisotropic Interdiffusion Coefficients in hcp Mg-Al alloys
2019Co-Authors: Wang Jingya, Xu Guanglong, Zheng Weisen, Llorca Javier, Cui YuwenAbstract:A high-throughput experimental approach is presented to extract the anisotropic Interdiffusion Coefficient by combining information over the composition profiles obtained by the electron probe microanalysis (EPMA) and the grain orientation spectrum by the electron backscatter diffraction (EBSD) on polycrystalline diffusion couples. Following the forward-simulation scheme, the Interdiffusion Coefficients in grains with diverse orientation are obtained and subsequently used to determine the anisotropic Interdiffusion Coefficients perpendicular (D_\perp (x)) and parallel (D_\parallel (x)) to the c axis of the hcp Mg lattice in a Mg-Al alloy as a function of the Al solute content at 673 K and 723 K, respectively. It was found that the Interdiffusion Coefficients generally increased with the Al content and the rotation angle with respect to the c axis with a valley point around {\theta} approx 30 {\deg} at 723 K. And it was noticed that diffusion along the basal plane was always faster than along the c axis. A comprehensive explicit expression of the Interdiffusion Coefficients was provided as a function of Al content, grain orientation and temperature. The anisotropic impurity diffusion Coefficients of Al in hcp Mg derived by the extrapolation of the results in this paper are in good agreement with first principles calculations in the literature
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High-throughput extraction of the anisotropic Interdiffusion Coefficients in hcp Mg–Al alloys
'Elsevier BV', 2019Co-Authors: Wang Jingya, Xu Guanglong, Zheng Weisen, Llorca-martínez F. Javier, Cui YuwenAbstract:A high-throughput experimental approach is presented to extract the anisotropic Interdiffusion Coefficient by combining information over the composition profiles obtained by the electron probe microanalysis (EPMA) and the grain orientation spectrum by the electron backscatter diffraction (EBSD) on polycrystalline diffusion couples. Following the forward-simulation scheme, the Interdiffusion Coefficients in grains with diverse orientation are obtained and subsequently used to determine the anisotropic Interdiffusion Coefficients perpendicular () and parallel () to the c axis of the hcp Mg lattice in a Mg–Al alloy as a function of the Al solute content at 673 K and 723 K, respectively. It was found that the Interdiffusion Coefficients generally increased with the Al content and the rotation angle with respect to the c axis with a valley point around at 723 K. And it was noticed that diffusion along the basal plane was always faster than along the c axis. A comprehensive explicit expression of the Interdiffusion Coefficients was provided as a function of Al content, grain orientation and temperature. The anisotropic impurity diffusion Coefficients of Al in hcp Mg derived by the extrapolation of the results in this paper are in good agreement with first principles calculations in the literature.This work was supported by the Natural Science Funds of China [Grant no. 51571113] and by the European Research Council under the European Union's Horizon 2020 research and innovation programme (Advanced Grant VIRMETAL, grant Agreement no. 669141). Ms. J-Y. Wang acknowledges the financial support from the China Scholarship Council (Grant no. 201506890002). GX acknowledges the support from the Natural Science Funds of China [Grant no. 51701094].Peer reviewe
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Diffusion Research in BCC Ti-Al-Zr Ternary Alloys
'Springer Science and Business Media LLC', 2019Co-Authors: Fan Fujun, Gu Yuanyu, Xu Guanglong, Chang Hui, Cui YuwenAbstract:Diffusion behavior in the BCC Ti-Al-Zr ternary alloys was experimentally investigated at 1273 K (1000 °C) and 1473 K (1200 °C) by means of the diffusion-couple technique. Upon the Whittle-Green and generalized Hall methods, the inter- and impurity diffusion Coefficients were respectively extracted from the composition profiles acquired by the electron microprobe analysis (EPMA) and subsequently represented by the error function expansion. The extracted main Interdiffusion Coefficient D~AlAlTi increases with increasing the content of either Al or Zr, and the increase is appearing more considerably at the higher temperature. However, D~ZrZrTi was noticed to decrease with the increase of Al and Zr contents at 1273 K (1000 °C) while there is an upward trend at 1473 K (1200 °C). The impurity diffusion Coefficients of Al in Ti-Zr binary alloys, DAl(Ti - Zr)*, and of Zr in Ti-Al binary alloys, DZr(Ti - Al)*, increase with increasing the Zr and Al contents respectively. A comparison of average main Interdiffusion Coefficient D~XXTi¯ made among ten Ti-Al-X ternary systems suggests that the Zr diffusion is most comparable to Cr and could operate via a vacancy-controlled mechanism
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Diffusion research in BCC Ti-Al-Zr ternary alloys
'Springer Science and Business Media LLC', 2019Co-Authors: Fan Fujun, Gu Yuanyu, Xu Guanglong, Chang Hui, Cui YuwenAbstract:Diffusion behavior in the BCC Ti-Al-Zr ternary alloys was experimentally investigated at 1273 K (1000 °C) and 1473 K (1200 °C) by means of the diffusion-couple technique. Upon the Whittle-Green and generalized Hall methods, the inter- and impurity diffusion Coefficients were respectively extracted from the composition profiles acquired by the electron microprobe analysis (EPMA) and subsequently represented by the error function expansion. The extracted main Interdiffusion Coefficient D~TiAlAl increases with increasing the content of either Al or Zr, and the increase is appearing more considerably at the higher temperature. However, D~TiZrZr was noticed to decrease with the increase of Al and Zr contents at 1273 K (1000 °C) while there is an upward trend at 1473 K (1200 °C). The impurity diffusion Coefficients of Al in Ti-Zr binary alloys, D∗Al(Ti - Zr), and of Zr in Ti-Al binary alloys, D∗Zr(Ti - Al), increase with increasing the Zr and Al contents respectively. A comparison of average main Interdiffusion Coefficient D~TiXX¯¯ made among ten Ti-Al-X ternary systems suggests that the Zr diffusion is most comparable to Cr and could operate via a vacancy-controlled mechanism.This research was funded by the Defense Industrial Technology Development Program of China [No. JCKY2018414C020]. YC acknowledges the support from the Natural Science Funds of China [Grant No. 51571113]. GX was funded by the Natural Science Funds of China [Grant No. 51701094] and the Natural Science Funds of Jiangsu Province [Grant No. BK20171014]. FF and YG would like to thank the support from the Synergetic Innovation Center for Advanced Materials, Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University.Peer reviewe
Jiang Y Wang - One of the best experts on this subject based on the ideXlab platform.
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determination of Interdiffusion Coefficient in nanolayered structures by auger electron spectroscopical sputter depth profiling
Advanced Materials Research, 2011Co-Authors: Jiang Y WangAbstract:A general method was developed for determination of Interdiffusion Coefficient in nanolayered structures by Auger electron spectroscopical (AES) sputter depth profiling. The procedures of this method are as follows: (1) the concentration depth profile of annealed sample is calculated from its as-grown layered structure by adopting a suitable diffusion model; (2) this diffusion concentration depth profile is convoluted with a resolution function provided by the mixing-roughness-information depth (MRI)-model and as a result a calculated AES depth profile is obtained; (3) the Interdiffusion Coefficient is determined by fitting the calculated AES depth profile to the measured one. As an example, the Interdiffusion Coefficient parameters, the pre-exponential factor and the activation energy, were determined as 4.7×10-18 m2/s and 0.76 eV, respectively, for a GexSi1-x/Si multilayered nanostructure with Ge-Si alloyed layers of 2.2, 4.3 and 2.2 nm thickness in Si matrix.
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a new method for the determination of the diffusion induced concentration profile and the Interdiffusion Coefficient for thin film systems by auger electron spectroscopical sputter depth profiling
Journal of Materials Research, 2004Co-Authors: Jiang Y WangAbstract:A new Auger electron spectroscopical sputter depth profiling method was developed to determine the Interdiffusion Coefficient for the initial stage of diffusion annealing of thin films. The method is based on (i) adoption of an Interdiffusion model appropriate for the specimen investigated and (ii) convolution of an accordingly calculated diffusion-induced concentration profile with the smearing effects due to atomic mixing, surface/interface roughness, escape depth of the Auger electrons, and preferential sputtering. The diffusion-induced concentration profile and the Interdiffusion Coefficient are determined by fitting in an iterative least-squares procedure of the calculated Auger electron spectroscopical depth profile to the measured one. The method was applied to bilayered and multilayered structures, exhibiting dominant grain-boundary diffusion and dominant volume diffusion, respectively. A very small extent of Interdiffusion, characterized by diffusion distances as small as 1 nm, could be quantified.
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determination of the Interdiffusion Coefficient for si al multilayers by auger electron spectroscopical sputter depth profiling
Thin Solid Films, 2003Co-Authors: Jiang Y Wang, A Zalar, Yonghao ZhaoAbstract:Initial stage Interdiffusion processes in Si/Al multilayer structures were studied quantitatively by means of Auger electron spectroscopical sputter depth profiling. The Al sublayers and the Si sublayers were sputter deposited onto a Si(111) substrate. The initial stage of the Interdiffusion at the location of the Si/Al interfaces was induced by heating the specimens isothermally in an argon atmosphere at 150, 165 and 180 °C for 20 min, and at 165 °C, additionally, for 10 and 30 min. It was found that, in such sputtering prepared multilayer structures, Interdiffusion across interfaces near the surface of the multilayer is faster than across interfaces in the deeper part of the layer. Measured depth profiles of the annealed specimens were compared with that of the as-deposited specimen after quantitative evaluation according to the so-called MRI (mixing-roughness-information depth)-model. As a result, values of the Interdiffusion Coefficient as a function of the depth beneath the surface were obtained.
Xu Guanglong - One of the best experts on this subject based on the ideXlab platform.
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Diffusion research in HCP Mg–Al–Sn ternary alloys
'Elsevier BV', 2020Co-Authors: Zhou Zhengfei, Gu Yuanyu, Xu Guanglong, Guo Yanhua, Cui YuwenAbstract:Diffusion behavior in the HCP Mg–Al–Sn ternary alloys was experimentally investigated at 673 K and 723 K by analyzing solid-state diffusion couples. From the composition profiles analytically represented by error function expansion, the inter- and impurity diffusion Coefficients were extracted by the Whittle-Green and generalized Hall methods respectively, which enable to establish the diffusion properties of the HCP Mg–Al–Sn alloys. The present results, together with the binary diffusion data of Mg–Al and Mg–Sn binaries, reveal that the average value of the main Interdiffusion Coefficient ~DMgSnSn over the investigated compositions is 1.39 times larger than ~DMgAlAl at 673 K and 1.36 times at 723 K, respectively, implying Sn diffuses comparably faster than Al in the HCP Mg–Al–Sn alloys. The main Interdiffusion Coefficients ~DMgAlAl and ~DMgSnSn and the impurity diffusion Coefficient D*Sn(Mg-Al) increases with increasing the content of diffusing element, either Al or Sn, however, D*Al(Mg-Sn) increases first and then decreases as the Sn composition increases. The cross Interdiffusion Coefficients are scattering, their composition dependences are not very conclusive, however, a trend that ~DMgAlSn and ~DMgSnA become negligibly small or even negative was evidenced as the content of Al or Sn approaches 0.The authors would like to acknowledge National Natural Science Foundation of China (Grant No. 51571113), Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, and Priority Academic Program Development of Jiangsu Higher Education Institution (PAPD).Peer reviewe
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High-throughput extraction of the anisotropic Interdiffusion Coefficients in hcp Mg-Al alloys
2019Co-Authors: Wang Jingya, Xu Guanglong, Zheng Weisen, Llorca Javier, Cui YuwenAbstract:A high-throughput experimental approach is presented to extract the anisotropic Interdiffusion Coefficient by combining information over the composition profiles obtained by the electron probe microanalysis (EPMA) and the grain orientation spectrum by the electron backscatter diffraction (EBSD) on polycrystalline diffusion couples. Following the forward-simulation scheme, the Interdiffusion Coefficients in grains with diverse orientation are obtained and subsequently used to determine the anisotropic Interdiffusion Coefficients perpendicular (D_\perp (x)) and parallel (D_\parallel (x)) to the c axis of the hcp Mg lattice in a Mg-Al alloy as a function of the Al solute content at 673 K and 723 K, respectively. It was found that the Interdiffusion Coefficients generally increased with the Al content and the rotation angle with respect to the c axis with a valley point around {\theta} approx 30 {\deg} at 723 K. And it was noticed that diffusion along the basal plane was always faster than along the c axis. A comprehensive explicit expression of the Interdiffusion Coefficients was provided as a function of Al content, grain orientation and temperature. The anisotropic impurity diffusion Coefficients of Al in hcp Mg derived by the extrapolation of the results in this paper are in good agreement with first principles calculations in the literature
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High-throughput extraction of the anisotropic Interdiffusion Coefficients in hcp Mg–Al alloys
'Elsevier BV', 2019Co-Authors: Wang Jingya, Xu Guanglong, Zheng Weisen, Llorca-martínez F. Javier, Cui YuwenAbstract:A high-throughput experimental approach is presented to extract the anisotropic Interdiffusion Coefficient by combining information over the composition profiles obtained by the electron probe microanalysis (EPMA) and the grain orientation spectrum by the electron backscatter diffraction (EBSD) on polycrystalline diffusion couples. Following the forward-simulation scheme, the Interdiffusion Coefficients in grains with diverse orientation are obtained and subsequently used to determine the anisotropic Interdiffusion Coefficients perpendicular () and parallel () to the c axis of the hcp Mg lattice in a Mg–Al alloy as a function of the Al solute content at 673 K and 723 K, respectively. It was found that the Interdiffusion Coefficients generally increased with the Al content and the rotation angle with respect to the c axis with a valley point around at 723 K. And it was noticed that diffusion along the basal plane was always faster than along the c axis. A comprehensive explicit expression of the Interdiffusion Coefficients was provided as a function of Al content, grain orientation and temperature. The anisotropic impurity diffusion Coefficients of Al in hcp Mg derived by the extrapolation of the results in this paper are in good agreement with first principles calculations in the literature.This work was supported by the Natural Science Funds of China [Grant no. 51571113] and by the European Research Council under the European Union's Horizon 2020 research and innovation programme (Advanced Grant VIRMETAL, grant Agreement no. 669141). Ms. J-Y. Wang acknowledges the financial support from the China Scholarship Council (Grant no. 201506890002). GX acknowledges the support from the Natural Science Funds of China [Grant no. 51701094].Peer reviewe
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Diffusion Research in BCC Ti-Al-Zr Ternary Alloys
'Springer Science and Business Media LLC', 2019Co-Authors: Fan Fujun, Gu Yuanyu, Xu Guanglong, Chang Hui, Cui YuwenAbstract:Diffusion behavior in the BCC Ti-Al-Zr ternary alloys was experimentally investigated at 1273 K (1000 °C) and 1473 K (1200 °C) by means of the diffusion-couple technique. Upon the Whittle-Green and generalized Hall methods, the inter- and impurity diffusion Coefficients were respectively extracted from the composition profiles acquired by the electron microprobe analysis (EPMA) and subsequently represented by the error function expansion. The extracted main Interdiffusion Coefficient D~AlAlTi increases with increasing the content of either Al or Zr, and the increase is appearing more considerably at the higher temperature. However, D~ZrZrTi was noticed to decrease with the increase of Al and Zr contents at 1273 K (1000 °C) while there is an upward trend at 1473 K (1200 °C). The impurity diffusion Coefficients of Al in Ti-Zr binary alloys, DAl(Ti - Zr)*, and of Zr in Ti-Al binary alloys, DZr(Ti - Al)*, increase with increasing the Zr and Al contents respectively. A comparison of average main Interdiffusion Coefficient D~XXTi¯ made among ten Ti-Al-X ternary systems suggests that the Zr diffusion is most comparable to Cr and could operate via a vacancy-controlled mechanism
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Diffusion research in BCC Ti-Al-Zr ternary alloys
'Springer Science and Business Media LLC', 2019Co-Authors: Fan Fujun, Gu Yuanyu, Xu Guanglong, Chang Hui, Cui YuwenAbstract:Diffusion behavior in the BCC Ti-Al-Zr ternary alloys was experimentally investigated at 1273 K (1000 °C) and 1473 K (1200 °C) by means of the diffusion-couple technique. Upon the Whittle-Green and generalized Hall methods, the inter- and impurity diffusion Coefficients were respectively extracted from the composition profiles acquired by the electron microprobe analysis (EPMA) and subsequently represented by the error function expansion. The extracted main Interdiffusion Coefficient D~TiAlAl increases with increasing the content of either Al or Zr, and the increase is appearing more considerably at the higher temperature. However, D~TiZrZr was noticed to decrease with the increase of Al and Zr contents at 1273 K (1000 °C) while there is an upward trend at 1473 K (1200 °C). The impurity diffusion Coefficients of Al in Ti-Zr binary alloys, D∗Al(Ti - Zr), and of Zr in Ti-Al binary alloys, D∗Zr(Ti - Al), increase with increasing the Zr and Al contents respectively. A comparison of average main Interdiffusion Coefficient D~TiXX¯¯ made among ten Ti-Al-X ternary systems suggests that the Zr diffusion is most comparable to Cr and could operate via a vacancy-controlled mechanism.This research was funded by the Defense Industrial Technology Development Program of China [No. JCKY2018414C020]. YC acknowledges the support from the Natural Science Funds of China [Grant No. 51571113]. GX was funded by the Natural Science Funds of China [Grant No. 51701094] and the Natural Science Funds of Jiangsu Province [Grant No. BK20171014]. FF and YG would like to thank the support from the Synergetic Innovation Center for Advanced Materials, Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University.Peer reviewe
A S M A Haseeb - One of the best experts on this subject based on the ideXlab platform.
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influence of ni nanoparticle on the morphology and growth of interfacial intermetallic compounds between sn 3 8ag 0 7cu lead free solder and copper substrate
Intermetallics, 2013Co-Authors: A S M A Haseeb, Mohd Rafie Johan, Paul Munroe, M Z QuadirAbstract:This paper reports on the effects of adding Ni nanoparticles to a Sn–3.8Ag–0.7Cu solder. The nanocomposite was prepared by manual blending of SAC solder paste with various percentages of Ni particles. Results showed that the addition of Ni nanoparticles did not bring any significant change in the onset melting temperature of the solder. An increase in the weight percentage of nanoparticles in the solder caused an increase of the wetting angle and a decrease of spreading rate. Moreover, the addition of Ni nanoparticles changed the interfacial intermetallic compound morphology from a scalloped structure into a planar type structure, enhanced the growth of (Cu,Ni)6Sn5 and suppressed that of Cu3Sn. The concentration of Ni in (Cu,Ni)6Sn5 was higher at the solder side compared with the substrate side. No nickel was detected in the Cu3Sn phase. Ni nanoparticle additions caused an increase in the Interdiffusion Coefficient in (Cu,Ni)6Sn5, but a reduction in Cu3Sn. All these effects found in the Ni nanoparticle doped solder are similar to the case when Ni is added as an alloying element. Hence, it is suggested that Ni nanoparticles dissolve into the molten solder and influence the intermetallic compound formation through conventional alloying effects.
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effects of co nanoparticle addition to sn 3 8ag 0 7cu solder on interfacial structure after reflow and ageing
Intermetallics, 2011Co-Authors: A S M A Haseeb, Tay See LengAbstract:Effects of Co nanoparticle additions to Sne3.8Age0.7Cu on the structure of solder/copper interface have been studied after reflow and high temperature ageing (150 � C, up to 1008 h). Results show that the Co nanoparticles substantially suppress the growth of Cu3Sn but enhance Cu6Sn5 growth. Cobalt nanoparticles reduce Interdiffusion Coefficient in Cu3Sn. It is suggested that the Co nanoparticles undergo surface dissolution during reflow and exert their influence, at least partially, through alloying effect.