Papers by Keyword: Compression Speed

Abstract: Expandable polystyrene and expandable polyethylene foams are frequently used in packaging of products. The study on their cushioning properties is important for the design of the transport package. The effect of compression speed and multiple reloading on the cushioning properties of HDEPS, LDEPS and HDEPE was studied in this paper. The results indicate that the cushioning properties of HDEPS and LDEPS are affected obviously by the compression speed, but the change of the cushioning properties for LDEPE was unconspicuous with the compression speed. LDEPE appeared obvious fatigue after twice reloads.

Abstract: Magnesium alloys are poor in ductility at room temperature and it is known that the cold working is very difficult. Therefore, the development of forming methods, especially at normal temperature, is highly expected [1]. In this paper, AZ91 magnesium block were accelerated more than 100 m/s and the magnesium alloy was well deformed into the die gap. The cross-sectional microstructure was characterized and the deformation of the magnesium was discussed.

Abstract: As reported in the previous report, increasing velocity by high-speed impulsive energy could improve the formability of AZ31 magnesium alloy. The improvement of ductility of AZ31 magnesium alloys can be observed, which is difficult to observe in usual cold forging techniques. This paper (Part II) is a coutinuation of the reported work in the previous paper. The forming of the AZ31 casting magnesium alloy was done. The hardness distribution of the test specimen was investigated for each experiment, and the microstructures are analyzed. The microstructural results indicate that adiabatic shear bands are formed and the microstructure is changed by the formation of huge amount of fine grained recrystallized structure. Furthermore, solid state is retained in the materials as well as the surface. [1]