The anisotropic plastic deformation behavior of as-extruded ZK60 magnesium alloy at room temperature (RT) was investigated by compressive and tensile testing in different directions, i.e. the loading axis oriented at 0°, 45° and 90° to the extrusion direction. The relationship between texture and plastic deformation behavior were examined. The results show that the extruded ZK60 alloy exhibits a strong ring fiber texture. The mechanical properties are strongly orientation dependent. In tension testing, the 0° specimen exhibited higher yield strength and lower elongation. In compression testing, however, ZK60 alloy exhibited almost the same yield strength in three directions. The anisotropic plastic deformation behavior is due to strong fiber texture and the lower symmetry of the hexagonal close packed (hcp) structure of ZK60 alloy. The correlation between texture and mechanical behaviour offers the possibility to improve the mechanical properties of magnesium alloy by optimization of the material production process.anisotropic, plastic deformation behavior, ZK60 Mg alloy, texture, mechanical property
Aluminium castings have been widely used in many industries, including automotive, aerospace, telecommunication, construction, consumer products, etc., due to their lightweight, good electric and thermal conductivity, and electromagnetic interference/radio frequency interference (EMI/RFI) shielding properties. The main applications of aluminium castings are in automotive industry. For lighweighting purposes, more and more aluminium castings are used in the automotive vehicle structures to reduce weight, improve fuel efficiency, and reduce greenhouse gas emissions. However, due to the features of cast aluminium, such as porosity, poor surface quality, a tendency toward hot cracking, and low ductility, joining these materials is problematic. In this paper, the joining technologies for aluminium castings and the related issues, mainly cracking and porosity, are reviewed. The current state-of-the-art of joining technologies is summarized, and areas for future research are recommended.
One of the key issues limiting the application of Al-Mg-Zn-Cu alloys in the automotive industry is forming at a low cost. Isothermal uniaxial compression was accomplished in the range of 300–450 °C, 0.001–10 s−1 to study the hot deformation behavior of an as-cast Al-5.07Mg-3.01Zn-1.11Cu-0.01Ti alloy. Its rheological behavior presented characteristics of work-hardening followed by dynamic softening and its flow stress was accurately described by the proposed strain-compensated Arrhenius-type constitutive model. Three-dimensional processing maps were established. The instability was mainly concentrated in regions with high strain rates or low temperatures, with cracking being the main instability. A workable domain was determined as 385–450 °C, 0.001–0.26 s−1, in which dynamic recovery (DRV) and dynamic recrystallization (DRX) occurred. As the temperature rose, the dominant dynamic softening mechanism shifted from DRV to DRX. The DRX mechanisms transformed from continuous dynamic recrystallization (CDRX), discontinuous dynamic recrystallization (DDRX), and particle-stimulated nucleation (PSN) at 350 °C, 0.1 s−1 to CDRX and DDRX at 450 °C, 0.01 s−1, and eventually to DDRX at 450 °C, 0.001 s−1. The eutectic T-Mg32(AlZnCu)49 phase facilitated DRX nucleation and did not trigger instability in the workable domain. This work demonstrates that the workability of as-cast Al-Mg-Zn-Cu alloys with low Zn/Mg ratios is sufficient for hot forming.
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.