How would you……describe the overall significance of this paper? In order to discover the deformation mechanism in compression, L-shaped components of aluminum alloy are taken as specimen to investigate the influence of metal flow and deformation behavior in the forming process....describe this work to a materials science and engineering professional with no experience in your technical specialty? Research reports covering aspects of deformation in compression are mostly limited to simple cylinders or ring billets from above. As lightweight alloy requirements in the manufacture area increase, the proportion of the special shape aluminum alloy significantly increases. …describe this work to a layperson?The paper investigates deformation behavior in the compression process of L-shaped aluminum alloy, and verifies the technological experiments results. A theory has been established for 7075 L-shaped aluminum alloy compression deformation behavior research and developed for making a special billet compression deformation plan of large complex components in the prefabricated working procedure.In order to discover the deformation mechanism in compression, L-shaped components of aluminum alloy are taken as specimen to investigate the influence of metal flow and deformation behavior in the forming process. Research results show that when the sectional shape is fixed, the range of plastic zone in the deformation body is expanded with the increase of the height of the billet. In addition, the deformation billet has a tendency to change from convexity both inside and outside to convexity inside outside and concavity outside inside, and the complexity degree of deformation also increases. Flow interface in the deformation body deviates along the radial direction to the inside billet gradually. Moreover, when the height of billet is a constant, the flow interface disappears and the metal on the deformation billet has an outflow tendency entirely. The results agree with the numerical simulation through experiments verification.

This paper presents some experimental data on roll compaction concrete cofferdam vibration induced by underwater explosion. A formula for the bubble pulse period of underwater explosion is proposed via dimension analysis and compared with Cole formula. An experiential formula is summarized on the relation among the structure vibration velocity, explosive charge and the distance from charge to structure. The formula indicates that the structure vibration velocity is directly proportional to square root of the charge when the charge package was near the structure. When the distance is farther between the charge and the cofferdam, the peak particle velocity (PPV) is smaller.