“…Earlier studies have reported that I-phase has a three-dimensional quasiperiodic structure, which has particular properties such as high hardness, coherence with the matrix and low surface energy [12]. Researchers have found that W-phase and LPSO phase can also significantly improve the mechanical properties of Mg alloys [13][14][15][16]. In a recent study, Wang et al found that W-phase and LPSO phase may play a composite strengthening role together [17].…”
Effects of different Y contents (0, 0.3, 0.7, 1.5, 3, 5 and 10 wt.%) on the microstructure, thermal stability and mechanical properties of Mg-3Zn-1Mn (ZM31) alloys were systematically studied. The existence form and action mechanism of Y in the experimental alloys were investigated. The results revealed that with the change of Y content, the main phases of the ZM31-xY alloys changed from Mg7Zn3 phase, I-phase, I + W-phase, W-phase, W + LPSO phase to LPSO phase. When Y content was low (≤1.5%), hot extrusion could break up the residual phases after homogenization to form dispersed fine rare-earth phase particles, and fine second phases would also precipitate in the grain, which could inhibit the grain growth. When Y content was high (≥3%), the experimental alloys were only suitable for high-temperature extrusion due to the formation of the high heat stable rare-earth LPSO phase. In addition, Y could evidently enhance the mechanical properties of the as-extruded ZM31 alloy, of which the ZM31-10Y alloy had the best mechanical properties, that is, the tensile and yield strengths are 403 MPa and 342 MPa. The high strengths of the alloys were mainly determined by fine grain strengthening, rare-earth phase strengthening and dispersion strengthening of fine α-Mn particles.
“…Earlier studies have reported that I-phase has a three-dimensional quasiperiodic structure, which has particular properties such as high hardness, coherence with the matrix and low surface energy [12]. Researchers have found that W-phase and LPSO phase can also significantly improve the mechanical properties of Mg alloys [13][14][15][16]. In a recent study, Wang et al found that W-phase and LPSO phase may play a composite strengthening role together [17].…”
Effects of different Y contents (0, 0.3, 0.7, 1.5, 3, 5 and 10 wt.%) on the microstructure, thermal stability and mechanical properties of Mg-3Zn-1Mn (ZM31) alloys were systematically studied. The existence form and action mechanism of Y in the experimental alloys were investigated. The results revealed that with the change of Y content, the main phases of the ZM31-xY alloys changed from Mg7Zn3 phase, I-phase, I + W-phase, W-phase, W + LPSO phase to LPSO phase. When Y content was low (≤1.5%), hot extrusion could break up the residual phases after homogenization to form dispersed fine rare-earth phase particles, and fine second phases would also precipitate in the grain, which could inhibit the grain growth. When Y content was high (≥3%), the experimental alloys were only suitable for high-temperature extrusion due to the formation of the high heat stable rare-earth LPSO phase. In addition, Y could evidently enhance the mechanical properties of the as-extruded ZM31 alloy, of which the ZM31-10Y alloy had the best mechanical properties, that is, the tensile and yield strengths are 403 MPa and 342 MPa. The high strengths of the alloys were mainly determined by fine grain strengthening, rare-earth phase strengthening and dispersion strengthening of fine α-Mn particles.
“…The XRD analysis results of as-cast Mg–4Y/Nd–2Zn alloys are given in Figure 2. Mg–4Y–2Zn alloy contains α-Mg and an X-Mg 12 YZn phase with a long period stacking order (LPSO) structure [10,16–18,28,29], while the Mg–4Nd–2Zn alloy contains α-Mg and the W-Mg 3 Zn 3 Nd 2 phase with a face-centre cubic structure [25,26]. Figure 1 Microstructure of as-cast Mg–4Y/Nd–2Zn alloys: (a) Mg–4Y–2Zn and (b) Mg–4Nd–2Zn. Figure 2 XRD patterns of as-cast Mg–4Y/Nd–2Zn alloys.…”
Section: Resultsmentioning
confidence: 99%
“…There are three kinds of ternary phases in the Mg-Zn-Y system alloys, such as X phase (Mg 12 ZnY, long period stacking ordered (LPSO) structure), I phase (Mg 3 Zn 6 Y, icosahedral quasicrystal structure, quasi-periodically ordered) and W phase (Mg 3 Zn 3 Y 2 , cubic structure). The formation and quantity of the three phases are related to the Zn/Y atomic ratio [16][17][18][19][20][21][22][23]. T phase (Mg 56 Nd 15 Zn 29 , c-base-centredorthorhombic structure) and W phase (Mg 3 Zn 3 Nd 2 , face-centred cubic structure) exist in Mg-Zn-Nd system alloys.…”
Optical microscopy, scanning electron microscopy, X-ray diffraction and tensile testing were performed to investigate the microstructure and mechanical properties of as-cast Mg–4Y/Nd–2Zn alloys. The results show that the secondary dendritic arm spacing for the Mg–4Y–2Zn alloy is smaller than that for the Mg–4Nd–2Zn alloy, and that X-Mg12YZn or W-Mg3Zn3Nd2 form in Mg–4Y/Nd–2Zn alloys. The lamellar X phase distributes at the grain boundary, pointing into the grains, whereas the rod-like W phase preferentially segregates at the triangle junction of the grain boundary. The greater grain boundary strengthening effect and the smaller fragmentation effect of the brittle eutectic phases leads to the as-cast Mg–4Y–2Zn alloy having better comprehensive mechanical properties. The fracture mechanism for as-cast Mg–4Y/Nd–2Zn alloys is quasi-cleavage fracture.
“…Magnesium and its alloy have the advantages of light weight, high specific strength, excellent damping, as well as good heat conduction properties and electrical conductivity [10], which are regarded as the potential electromagnetic shielding materials. Song et al obtained different intensity of basal textures of AZ31 by varying the strain, which amplified the impedance mismatch between the external free space and sheets, the SE value was improved by the increase of reflection attenuation [11].…”
Laminated composite with multi-layer interfaces has better electromagnetic interference shielding performance, which has attracted great attention. In this work, magnesium matrix laminated structure materials were prepared through Accumulative Roll Bonding (ARB). Microstructure, electrical conductivity and electromagnetic interference (EMI) shielding effectiveness (SE) of ME21/Mg laminated materials were investigated to understand the effect of layered structure and the change of microstructure on the electromagnetic shielding property. The results showed: the precipitated secondary phase and introduced interfaces could provide multiple reflections, attenuate the electromagnetic waves and improve the SE value. The electrical conductivity of 2-cycle increased to 21.04*106S/m，which was 17.74% higher than that of ME21 alloy, the intensity of texture of ME21 layer increased with the rolling passes, which contributed to the improvement of the electrical conductivity as well as the attenuation of reflection. The layered composite exhibited better shielding effectiveness compared with the ME21, in the 8.2-12.4 GHz test frequency, the SE was 98-107dB. The shielding mechanism of layered materials was explained, which provided guiding for the efficient shielding of electromagnetic waves.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
