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Abstract The as-cast Mg-4Zn-2Gd-0.5Ca alloy mainly contained I phase and W phase, while the I phase dissolved into Mg substrate after homogenization treatment which improved the alloy's corrosion resistance. After the application of multidirectional forging (MDF), the grains were refined obviously accompanied with the precipitation of I phase. With the increasing pass of MDF, both the size of dynamic recrystallized grains and the amount of precipitated I phase increased. The corrosion resistance of Mg-4Zn-2Gd-0.5Ca alloy became worse after 1 pass of MDF as compared with the as-homogenizated condition because of the precipitation of I phase. Neverthless, the corrosion resistance of the as-MDFed Mg-4Zn-2Gd-0.5Ca alloy deteriorated with the increasing pass of MDF. As compared with grain refinement, the precipitated I phase is thought to play a main role on the corrosion behavior of Mg-4Zn-0.5Ca alloy. Graphical abstract Image 1 Highlights • Dissolution of I phase lead to the improved corrosion resistance of as-HTed alloy. • MDF results in the grain refinement and precipitated I phase of Mg-4Zn-2Gd-0.5Ca alloy. • The influence of precipitated I phase on corrosion resistance is larger than grain refinement. [ABSTRACT FROM AUTHOR]

Abstract: As increasing worldwide demand for portable consumer electronics drives development of smaller, faster, more powerful electronic devices, components in these devices must become smaller, more precise, and more robust. Often, failure of these devices comes as a result of failure of the package (i.e. when a mobile phone is dropped) and specifically comes as a result of failure of solder interconnects. As a result, stronger more reliable solder materials are needed. In this paper, the constitutive responses of three solder materials (Sn63Pb37, Sn62Pb36Ag2, and Sn96.5Ag3Cu0.5) are analyzed as a function of temperature (−196°C to 60°C) and strain rate (10−3 to >103 s−1). The lead-free Sn96.5Ag3Cu0.5 possessed the highest yield stress of the three solders at all tested strain rates and temperatures, and all solder microstructures which displayed a mechanical response that was sensitive to temperature exhibited grain coarsening with increasing plastic strain, even at room temperature. [Copyright &y& Elsevier]

In this work, to enhance the mineralization of the organic dyes, the g-C 3 N 4 (Ag)/Gr/TiO 2 Z-scheme photocatalyst was successfully prepared by hydrothermal method. The XRD and XPS results showed that the nanocomposite was constructed. The SEM and EDS results showed that the morphology of g-C 3 N 4 (Ag)/Gr/TiO 2 was that TiO 2 nanoparticles distributed on the surface of the Gr/g-C 3 N 4 layers. The photocatalytic performance of the prepared samples was evaluated by the photocatalytic degradation and mineralization of RhB under visible light irradiation. The degradation efficiency of RhB on g-C 3 N 4 (Ag)/Gr/TiO 2 reached 99.7% within 2 h, and the kinetic rate (0.0431 min−1) was 7.1, 7.1, 2.2, 2.0 and 1.3 times higher than those of g-C 3 N 4 , TiO 2 , g-C 3 N 4 (Ag)/Gr, g-C 3 N 4 /TiO 2 , and g-C 3 N 4 /Gr/TiO 2 , respectively. The total organic carbon (TOC) removal results showed that the mineralization efficiency of RhB on this composite was as high as 74.5% after 2 h of reaction time. During the photocatalytic process, it was speculated that Gr acted as the electron transporter between TiO 2 and g-C 3 N 4 , which reduced the recombination efficiency of photo-generated charge carriers, and silver clusters acted as an electron reservoir to accelerate the reduction reaction of photo-generated electrons on the g-C 3 N 4 conduction band, and further improved the photocatalytic performance. [ABSTRACT FROM AUTHOR]

Abstract In order to find suitable degradable materials for the fracturing ball of wolf howl, a new as-cast Mg-4Zn-xNi (x = 0.5, 1, 2, 4 wt.%) alloys were prepared. Results indicated that the addition of Ni element lead to the formation of Mg 2 Ni phase in the Mg-4Zn-xNi alloys, which responsible for the increase of compressive strength and micro-hardness of Mg-Zn series alloy. Nevertheless, formation of Mg 2 Ni phase with high electrochemical potential can also accelerate the degradation rate of Mg-Zn series alloy. Accompanied with the increasing Ni content, the amount of Mg 2 Ni phase increases simultaneously, which aggravate galvanic corrosion and results in the higher degradation rate of Mg-Zn series alloys. The Mg-Zn-Ni alloy with moderate strength and higher degradation rate are obtained in present work, which is thought as an ideal candidate for the fracturing ball of wolf howl. Highlights • Addition of Ni is propitious to improve the degradation rate of Mg-Zn series alloy. • Formation of Mg 2 Ni phase is the reason for the rapid degradation rate of Mg-Zn-Ni alloys. • The present Mg-Zn-Ni alloys exhibit the fastest degradation rate among the reported work in the reference. [ABSTRACT FROM AUTHOR]