985 resultados para mesothelioma, lysine acetyltransferase, epigenetics, MG 149, inflammation
Resumo:
The influence of the addition of mischmetal (MM) and tin (Sn) (total content of mischmetal and tin = 4 wt.%) on the microstructure, aging behavior and mechanical properties of Mg-6Zn-5Al-based alloys has been investigated. The microstructure of the as-cast alloys consists of alpha-Mg. Mg-32(Al,Zn)(49), Al2Mg5Zn2, Mg2Sn and Al2MMZn2 phases, and the morphology of these intermetallic phases varies with different MM and Sri additions.
Resumo:
Mg-8Gd-2Y-Nd-0.3Zn (wt%) alloy was prepared by the high pressure die-cast technique. The microstructure, mechanical properties in the temperature range from room temperature to 573 K, and strengthening mechanism were investigated. It was confirmed that the Mg-Gd-based alloy with high Gd content exhibited outstanding die-cast character. The die-cast alloy was mainly composed of small cellular equiaxed dendrites and the matrix. The long lamellar-shaped stacking compound of Mg3X (X: Gd, Y, Nd, and Zn) and polygon-shaped.
Resumo:
Microstructure and mechanical properties of as-cast and heat-treated Mg-12.3Zn-5.8Y-1.4Al (ZYA1261) alloy were investigated. The phase compositions of the as-cast alloy are alpha-Mg, Mg3YZn6 (I-phase), Mg(3)y(2)Zn(3) (W-phase), Mg12YZn (Z-phase), Mg24Y5, MgZn and a small quantity of Al-containing phase.
Resumo:
The Mg-8.31Gd-1.12Dy-0.38Zr (mass%) alloy was prepared by casting technology, and the microstructure, age hardening behavior and mechanical property have been investigated. It is noted that the alpha-Mg and the different Mg-RE (RE = Gd/Dy) compounds are subsistent in the as-cast and annealed state samples. The age hardening behavior is observed during the investigated temperature range, and the alloy exhibits high Vickers hardness, excellent ultimate tensile strength and yield strength at peak hardness.
Resumo:
The electrochemical corrosion behavior of Mg-6Al-0.4Mn and Mg-6Al-4RE-0.4Mn (RE = Mischmetal) alloys is investigated in 3.5% NaCl solution. The results of corrosion process, polarization behavior, and electrochemical impedance spectroscopy of the alloys reveal that Mg-6Al-4RE-0.4Mn exhibits enhanced corrosion resistance. The addition of RE stabilizes the solid solution and modifies the passive film through a finer microstructure.
Resumo:
Mg-8Gd-0.6Zr-1RE (RE = La or Ce, wt.%) alloys were prepared by casting. The microstructures, age hardening behavior and mechanical properties were investigated. The results show that the addition of 1 wt.% La or Ce to a Mg-8Gd-0.6Zr alloy reduces the dendrite arm spacing and slightly improves the mechanical properties and age hardening response.
Resumo:
Microstructure and mechanical properties of peak-aged Mg-4.5Zn-xGd (x=0, 0.5, 1.0 and 1.5 wt.%) alloys have been investigated. The results showed that the grain size of the alloys was refined gradually with increasing Gd. Mg5Gd and Mg3Gd2Zn3 phases were found in the Gd-containing alloys. The strengths were greatly improved with Gd additions, and the highest strength level was obtained in the Mg-4.5Zn-1.5Gd alloy, in which the ultimate tensile strength and yield strength were 231 MPa and 113 MPa, respectively.
Resumo:
Microstructure and mechanical properties of Mg-4.5Zn-xNd (x = 0, 1 and 2, wt%) alloys heat-treated at 603 K for 2 It have been investigated. T-phase (an Mg-Zn-Nd ternary phase) was observed in the Nd containing alloys. The optimal mechanical properties were obtained in the Mg-4.5Zn-1Nd alloy, and the ultimate tensile strength and yield strength were 228 and 79 MPa, respectively. Through comparing with the Mg-4.5Zn alloy, the increments of ultimate tensile strength and yield strength were 51 and 17 MPa.
Resumo:
Microstructures and mechanical properties of the peak-aged Mg-4.5Zn-xGd (x = 0, 2, 3 and 5 wt.%) alloys have been investigated. The results showed that grain size increased with increasing Gd. Phase analysis showed that MgZn2 phase was observed in the Mg-4.5Zn alloy. While with Gd additions, Mg3Gd and Mg3Gd2Zn3 phases formed, and the volume fraction of the Mg3Gd2Zn3 phase increased with increasing Gd. Tensile test results indicated that the optimal mechanical properties were obtained in the Mg-4.5Zn-2Gd alloy, and the ultimate tensile strength and yield strength were 215 MPa and 121 MPa, respectively.
Resumo:
The Mg-8Gd-0.6Zr-xEr (x = 1, 3 and 5 mass%) alloys were prepared by casting technology, and the microstructures, age hardening behaviors and mechanical properties of alloys have been investigated. Microstructures of the alloys are characterized by the presence of rosette-shaped equiaxed grains. The age hardening behaviors and the tensile properties are enhanced by adding Er element. The maximum aged hardness of Mg-8Gd-0.6Zr-5Er alloy is 97, it is nearly 1.24 times higher than that of Er-free alloy.
Resumo:
A refined version of the edge-to-edge matching model is described here. In the original model, the matching directions were obtained from the planes with all the atomic centers that were exactly in the plane, or the distance from the atomic center to the plane which was less than the atomic radius. The direction-matching pairs were the match of straight rows-straight rows and zigzag rows-zigzag rows. In the refined model, the matching directions were obtained from the planes with all the atomic centers that were exactly in the plane.
Resumo:
Die-cast Mg-4Al-0.4Mn-xNd(x = 0, 1, 2, 4 and 6 wt.%) magnesium alloys were prepared successfully and influences of Nd on the microstructure, mechanical properties and corrosion behavior of the Mg-4Al-0.4Mn alloy have been investigated. The results showed that with the addition of Nd binary Al2Nd phase and Al11Nd3 phase. which mainly aggregated along the grain boundaries, were formed, and the relative ratio of above two phases was in correlation with the Nd content in the alloy. Meanwhile, the grain sizes were greatly reduced with the increasing Nd content. It was found that due to the addition of Nd both the tensile properties and corrosion resistance were improved substantially.
Resumo:
In order to study the properties of Mg-Al-RE (AE) series alloys, the Mg-4Al-4RE-0.4Mn (RE= La, Ce/La mischmetal or Ce) alloys were developed. Their microstructures, tensile properties and corrosion behavior have been investigated. The results show that the phase compositions of Mg-4Al-4La-0.4Mn alloy consist of alpha-Mg and Al11La3 phases. While two binary Al-RE (RE = Ce/La) phases, Al11RE3 and Al2RE, are formed in Mg-4Al-4Ce/La-0.4Mn alloy, and Al11Ce3 and Al2Ce are formed in Mg-4Al-4Ce-0.4Mn alloy.
Resumo:
In this study, compositional dependence of age hardening characteristics and tensile properties were investigated for Mg-4Ho-xY-0.6Zr alloys (x = 0, 3 5, and 7 wt%). The result showed that with increasing Y content, the hardness of the alloys increased in the as-quenched and aged-peak conditions. Considerable age hardening response was recognized for the alloys. When the alloy containing 7% Y showed the most remarkable age hardening response at aging temperature of 250 degrees C.
Resumo:
The Mg-8Gd-2Y-1Nd-0.3Zn-0.6Zr (wt.%) alloy sheet was prepared by hot extrusion technique, and the structure and mechanical properties of the extruded alloy were investigated. The results show that the alloy in different states is mainly composed of alpha-Mg solid solution and secondary phases of Mg5RE and Mg24RE5 (RE = Gd, Y and Nd). At aging temperatures from 200 degrees C to 300 degrees C the alloy exhibits obvious age-hardening response. Great improvement of mechanical properties is observed in the peak-aged state alloy (aged at 200 degrees C for 60 h), the ultimate tensile strength (sigma(b)), tensile yield strength (sigma(0.2)) and elongation (epsilon) are 376 MPa, 270 MPa and 14.2% at room temperature (RT), and 206 MPa. 153 MPa and 25.4% at 300 degrees C, respectively, the alloy exhibits high thermal stability.