Mechanical behavior and response mechanism of porous metal structures manufactured by laser powder bed fusion under compressive loading

Al Si10Mg porous protective structure often produces different damage forms under compressive loading,and these damage modes affect its protective function.In order to well meet the service requirements,there is an urgent need to comprehensively understand the mechanical behavior and response mechanism of AlSi10Mg porous structures under compressive loading.In this paper,Al Si10Mg porous structures with three kinds of volume fractions are designed and optimized to meet the requirements of high-impact,strong-energy absorption,and lightweight characteristics.The mechanical behaviors of AlSi10Mg porous structures,including the stress-strain relationship,structural bearing state,deformation and damage modes,and energy absorption characteristics,were obtained through experimental studies at different loading rates.The damage pattern of the damage section indicates that AlSi10Mg porous structures have both ductile and brittle mechanical properties.Numerical simulation studies show that the AlSi10Mg porous structure undergoes shear damage due to relative misalignment along the diagonal cross-section,and the damage location is almost at 45°to the load direction,which is the most direct cause of its structural damage,revealing the damage mechanism of AlSi10Mg porous structures under the compressive load.The normalized energy absorption model constructed in the paper well interprets the energy absorption state of Al Si10Mg porous structures and gives the sensitive location of the structures,and the results of this paper provide important references for peers in structural design and optimization.

New Method for Computer Identification Through Electromagnetic Radiation

The electromagnetic waves emitted from devices can be a source of information leakage and can cause electromagnetic compatibility(EMC)problems.Electromagnetic radiation signals from computer displays can be a security risk if they are intercepted and reconstructed.In addition,the leaks may reveal the hardware information of the computer,which is more important for some attackers,protectors and security inspection workers.In this paper,we propose a statistical distribution based algorithm(SD algorithm)to extracted eigenvalues from electromagnetic radiate video signals,and then classified computers by using classifier based on Bayesian and SVM.We can identify computers automatically and accurately through electromagnetic radiation by using the algorithm in our experiment environment.