Experimental and analytical assessment of the hypervelocity impact damage of GLAss fiber REinforced aluminum

This article addresses the response of GLAss fiber REinforced aluminum to hypervelocity impacts of micrometeoroid analogs at impact velocities of 7 km/s and beyond.In relation,the damage modes of different GLAss fiber REinforced aluminum configurations have been exemplified.The GLAss fiber REinforced aluminum configurations comprised six to twelve variably thick aluminum layers and up to four plies of glass fiber reinforced epoxy per composite laminate.Hypervelocity impact experiments have been conducted with the help of a two-stage light-gas gun,wherein aluminum-and stainless steel projectiles were launched at velocities up to 7.15 km/s.Visual inspection of the damage area suggested the dissipation of impact energy in elastic-plastic deformation,petalling,delamination,debonding,tensile failure of fibers,and pyrolysis of epoxy.A prevailing damage mode was not apparent albeit.The quasi-isotropic ply orientation of S2-glass/FM94-epoxy laminates promoted the interference of shockand rarefaction waves and suppressed the damage area of GLAss fiber REinforced aluminum.To discriminate between the impact performance of different GLAss fiber REinforced aluminum configurations,the energy dissipated in different damage modes of GLAss fiber REinforced aluminum has been assessed quantitatively.In terms of normalized energy,the cross-ply GLAss fiber REinforced aluminum dissipated higher energy in petal formation than in other primary damage modes.The normalized petalling energy was found to decline with the increase of impact energy.The outcomes of this study will help to optimize the GLAss fiber REinforced aluminum laminate,which will be employed as a bumper shield to prevent the fatal damage and the unzipping of a spacecraft pressure bulkhead.

大力增强人员的技能 审视在工业4.0智能化机器时代对高质量人力资源的同步需求

工业4.0需要特定的技能和人才。在一些国家,人力资源并未能满足这些需求。广大组织的员工必须更加具备智慧和技能,才能在这种新技术驱动的大环境下脱颖而出。为了解决人力资源在技能上的差距,就需要在学校教育之外进行更多的教育和培训。发展这些技能会付出必要的成本,但是这样做应被视为是保持质量符合性的重要组成部分。作者在本文中提供的相关建议,可以帮助学员在超越其学业成就之外,成为掌握高技能并拥有价值的人力资源。