In this set of experiments, the versatility of the University of Kent's light gas gun was utilised to obtain a selection of corroborative data regarding the formation and impact of metallic gunshot residues onto high purity silicon wafers. The results from the two experiments are presented. The first experiment investigated how the formation of metallic residues varied as gunshot residue analogues traversed through air under a range of pressures from 0.056 millibar (5.6 Pa) to 1 bar (100 kPa), using solely the energy released during primer ignition; the second involved firing a metallic powder mix of pre-determined composition (via a split-sabot) under vacuum at two velocities- 500 ms-1 and 2000 ms-1. This ensured that there was no ignition or heating of the powders, unlike the first experiment, and so the morphology of the particles collected would be solely due to impact. The residues on the substrates were then analysed using a cold Field Emission Gun Scanning Electron Microscope (FEG) and Energy Dispersive X-ray (EDX) detector. By separating the ignition process of the primers from the residue impacts, it allows for a closer look into the formation of these particles and helps determine whether their varied morphologies are due to the heating caused during the activation and combustion of the primer or whether its due to impact melting. This information can aid in the understanding of metallic particle formation in different pressure environments and give insight into the physical state of firearm residues when they impact a surface. Hydrocode modelling was also incorporated to corroborate the results observed during these experiments and gave results which mimicked the experimental data.
{"title":"Experiments using a light gas gun to investigate the impact melting of gunshot residue analogues","authors":"V. Spathis, M. Price","doi":"10.1115/hvis2019-030","DOIUrl":"https://doi.org/10.1115/hvis2019-030","url":null,"abstract":"\u0000 In this set of experiments, the versatility of the University of Kent's light gas gun was utilised to obtain a selection of corroborative data regarding the formation and impact of metallic gunshot residues onto high purity silicon wafers. The results from the two experiments are presented. The first experiment investigated how the formation of metallic residues varied as gunshot residue analogues traversed through air under a range of pressures from 0.056 millibar (5.6 Pa) to 1 bar (100 kPa), using solely the energy released during primer ignition; the second involved firing a metallic powder mix of pre-determined composition (via a split-sabot) under vacuum at two velocities- 500 ms-1 and 2000 ms-1. This ensured that there was no ignition or heating of the powders, unlike the first experiment, and so the morphology of the particles collected would be solely due to impact. The residues on the substrates were then analysed using a cold Field Emission Gun Scanning Electron Microscope (FEG) and Energy Dispersive X-ray (EDX) detector. By separating the ignition process of the primers from the residue impacts, it allows for a closer look into the formation of these particles and helps determine whether their varied morphologies are due to the heating caused during the activation and combustion of the primer or whether its due to impact melting. This information can aid in the understanding of metallic particle formation in different pressure environments and give insight into the physical state of firearm residues when they impact a surface. Hydrocode modelling was also incorporated to corroborate the results observed during these experiments and gave results which mimicked the experimental data.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"65 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91517009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Metallic shaped charge jets (SCJ) have been studied for many decades across multiple communities for applications ranging from military warheads to earth penetrators for accessing oil-rich areas [1]. Researchers have had varied success in modeling these jets using simulation codes such as CTH, ALEGRA, and ALE3D. Recently, a large amount of work has been performed at the US Army Research Lab investigating the behavior of jets with increasingly sophisticated experimental diagnostics. Advances in computational resources, code enhancements, and material models have allowed us to model jets and probe uncertainties caused by algorithms, equations of state (EOS), constitutive models, and any of the available parameters each one provides. In this work we explore the effects that various EOS and constitutive models have on the development and characteristics of a 65-mm diameter, 2D copper SCJ using the Sandia National Laboratories’ multiphysics hydrocode, ALEGRA [2]. Specifically, we evaluate the tabular SESAME 3320 [3], 3325 [4-5], and 3337 [6] EOS models, analytic EOS (ANEOS) 3331 [7], as well as the Johnson-Cook (JC) [8], Zerilli-Armstrong (ZA) [9], Preston-Tonks-Wallace (PTW) [10], Steinberg-Guinan-Lund (SGL) [11-12], and Mechanical Threshold Stress (MTS) [13] constitutive models. Note that while the SGL model supports rate-dependence, there is no current characterization for copper, thus we are using rate-independent version. We do not consider the MieGrüneisen equation of state here as we expect parts of the jet to be near or cross into melt.
{"title":"Effects of EOS and constitutive models on simulating copper shaped charge jets in ALEGRA","authors":"R. Doney, J. Niederhaus, T. Fuller, M. Coppinger","doi":"10.1115/hvis2019-010","DOIUrl":"https://doi.org/10.1115/hvis2019-010","url":null,"abstract":"\u0000 Metallic shaped charge jets (SCJ) have been studied for many decades across multiple communities for applications ranging from military warheads to earth penetrators for accessing oil-rich areas [1]. Researchers have had varied success in modeling these jets using simulation codes such as CTH, ALEGRA, and ALE3D. Recently, a large amount of work has been performed at the US Army Research Lab investigating the behavior of jets with increasingly sophisticated experimental diagnostics. Advances in computational resources, code enhancements, and material models have allowed us to model jets and probe uncertainties caused by algorithms, equations of state (EOS), constitutive models, and any of the available parameters each one provides. In this work we explore the effects that various EOS and constitutive models have on the development and characteristics of a 65-mm diameter, 2D copper SCJ using the Sandia National Laboratories’ multiphysics hydrocode, ALEGRA [2]. Specifically, we evaluate the tabular SESAME 3320 [3], 3325 [4-5], and 3337 [6] EOS models, analytic EOS (ANEOS) 3331 [7], as well as the Johnson-Cook (JC) [8], Zerilli-Armstrong (ZA) [9], Preston-Tonks-Wallace (PTW) [10], Steinberg-Guinan-Lund (SGL) [11-12], and Mechanical Threshold Stress (MTS) [13] constitutive models. Note that while the SGL model supports rate-dependence, there is no current characterization for copper, thus we are using rate-independent version. We do not consider the MieGrüneisen equation of state here as we expect parts of the jet to be near or cross into melt.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"90 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84311654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Schmalzer, J. Yeager, P. Bowden, D. Guildenbecher, J. Olles
Multi-fragment impact of energetic materials can provide the impetus initiation and growth to detonation when shockwaves from these discrete fragments collide. The Sandia hydrocode CTH is used with reactive burn modeling to identify relationships between spherical fragment separation distances, variable fragment arrival timing, and initiability in energetic materials. This work demonstrates that detonation is most likely to occur is when multiple fragments collide with a surface simultaneously, because of the cumulative pressure rise of two equal colliding waves compared to the colliding waves generated by fragment impacts offset in time.
{"title":"Experiment guided simulation of multi-fragment impact into PBXs","authors":"A. Schmalzer, J. Yeager, P. Bowden, D. Guildenbecher, J. Olles","doi":"10.1115/hvis2019-108","DOIUrl":"https://doi.org/10.1115/hvis2019-108","url":null,"abstract":"\u0000 Multi-fragment impact of energetic materials can provide the impetus initiation and growth to detonation when shockwaves from these discrete fragments collide. The Sandia hydrocode CTH is used with reactive burn modeling to identify relationships between spherical fragment separation distances, variable fragment arrival timing, and initiability in energetic materials. This work demonstrates that detonation is most likely to occur is when multiple fragments collide with a surface simultaneously, because of the cumulative pressure rise of two equal colliding waves compared to the colliding waves generated by fragment impacts offset in time.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83838227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Material fragmentation after a hypervelocity impact is of interest to predictive electro-optical and infrared (EO/IR) modeling. Successful comparisons with data require that submicron fragments are generated in such impacts; however, experimental data has so far been unable to produce fragments of this scale [e.g., 1-3]. This effort investigated the generation of predicted debris from hypervelocity impact of a sphere on a flat, semi-infinite plate. It is hypothesized that explicit modeling of grains, especially in the presence of void and varying grain properties, may lead to differences in predicted strain rates (locally higher) associated with the grain boundaries. Such an effect may lead to smaller predicted fragments sizes than when using the traditional bulk modeling approach and may provide improved understanding of fragmentation modeling in hypervelocity impacts. Comparisons of predicted strain rates at failure (a proxy for fragment size) and material temperature were made between simulations run using a bulk modeling approach and a mesoscale grain modeling approach.
{"title":"Mesoscale modeling and debris generation in hypervelocity impacts","authors":"Stephanie N. Q. Bouchey, J. Hollenshead","doi":"10.1115/hvis2019-017","DOIUrl":"https://doi.org/10.1115/hvis2019-017","url":null,"abstract":"\u0000 Material fragmentation after a hypervelocity impact is of interest to predictive electro-optical and infrared (EO/IR) modeling. Successful comparisons with data require that submicron fragments are generated in such impacts; however, experimental data has so far been unable to produce fragments of this scale [e.g., 1-3]. This effort investigated the generation of predicted debris from hypervelocity impact of a sphere on a flat, semi-infinite plate. It is hypothesized that explicit modeling of grains, especially in the presence of void and varying grain properties, may lead to differences in predicted strain rates (locally higher) associated with the grain boundaries. Such an effect may lead to smaller predicted fragments sizes than when using the traditional bulk modeling approach and may provide improved understanding of fragmentation modeling in hypervelocity impacts. Comparisons of predicted strain rates at failure (a proxy for fragment size) and material temperature were made between simulations run using a bulk modeling approach and a mesoscale grain modeling approach.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"54 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83842887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Reck, S. Hundertmark, R. Hruschka, A. Zeiner, B. Sauerwein, M. Schneider
The high-velocity launch of a projectile is subjected to a number of disturbances which exert an influence on the flight trajectory. In the case of sub-caliber projectiles, sabot separation is one of the critical aspects. In this work, we focus on the projectiles and the launch package of an electric railgun launch, i.e. on the behavior of the launch-package, when transitioning from the gun barrel to free-flight. This work further addresses the use of a hydrocode for creating numerical models which are capable of predicting the motion and deflection of the sabot parts during their separation from the projectile after exiting the muzzle. An earlier study showed that the air flow around the projectile and the sabot can be modeled with sufficiently high accuracy by means of a simulation code that uses an Eulerian description of the gas flow. Within a time interval of several milliseconds, just the duration that a projectile needs to enter quasi-stationary flight, viscous effects of the air or gas flow have relatively little influence on the sabot discard process. If the Eulerian gas flow is coupled with the Lagrangian structural parts, the mechanical response of the latter to the gas pressure can be complex in terms of deformation and damage, and in that way, can affect the gas flow. In this study, the hydrocode model is applied to a medium caliber launch package concept for accelerating long rod projectiles. The computed results agree well with the corresponding experimental values obtained from a launch package model test in the shock tunnel at Mach 4.5. This demonstrates that the presented hydrocode model can be used for launch package design optimizations with high confidence.
{"title":"Transitional ballistics of electric high-velocity launchers","authors":"B. Reck, S. Hundertmark, R. Hruschka, A. Zeiner, B. Sauerwein, M. Schneider","doi":"10.1115/hvis2019-092","DOIUrl":"https://doi.org/10.1115/hvis2019-092","url":null,"abstract":"\u0000 The high-velocity launch of a projectile is subjected to a number of disturbances which exert an influence on the flight trajectory. In the case of sub-caliber projectiles, sabot separation is one of the critical aspects. In this work, we focus on the projectiles and the launch package of an electric railgun launch, i.e. on the behavior of the launch-package, when transitioning from the gun barrel to free-flight. This work further addresses the use of a hydrocode for creating numerical models which are capable of predicting the motion and deflection of the sabot parts during their separation from the projectile after exiting the muzzle. An earlier study showed that the air flow around the projectile and the sabot can be modeled with sufficiently high accuracy by means of a simulation code that uses an Eulerian description of the gas flow. Within a time interval of several milliseconds, just the duration that a projectile needs to enter quasi-stationary flight, viscous effects of the air or gas flow have relatively little influence on the sabot discard process. If the Eulerian gas flow is coupled with the Lagrangian structural parts, the mechanical response of the latter to the gas pressure can be complex in terms of deformation and damage, and in that way, can affect the gas flow. In this study, the hydrocode model is applied to a medium caliber launch package concept for accelerating long rod projectiles. The computed results agree well with the corresponding experimental values obtained from a launch package model test in the shock tunnel at Mach 4.5. This demonstrates that the presented hydrocode model can be used for launch package design optimizations with high confidence.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82343727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Rainey, A. Stickle, A. Cheng, A. Rivkin, N. Chabot, O. Barnouin, C. Ernst
The Asteroid Impact Deflection Assessment (AIDA) collaboration is a joint ESA-NASA planetary defense collaboration that will include the first full-scale test of an asteroid deflection by kinetic impactor [1]. The AIDA collaboration comprises two independent spacecraft, the NASA-sponsored Double Asteroid Redirection Test (DART) and the ESA-led Hera. In September 2022 the DART spacecraft will impact the secondary member of the binary asteroid system 65803 Didymos (Didymos-B) at a speed of ~6.7 km/s and mass ~500 kg. The resulting period change in the orbit of Didymos-B will be measured using Earth-based observations. Hera will arrive post-impact and perform detailed measurements to characterize Didymos-B.
{"title":"Impact Modeling for the Double Asteroid Redirection Test Mission","authors":"E. Rainey, A. Stickle, A. Cheng, A. Rivkin, N. Chabot, O. Barnouin, C. Ernst","doi":"10.1115/hvis2019-038","DOIUrl":"https://doi.org/10.1115/hvis2019-038","url":null,"abstract":"\u0000 The Asteroid Impact Deflection Assessment (AIDA) collaboration is a joint ESA-NASA planetary defense collaboration that will include the first full-scale test of an asteroid deflection by kinetic impactor [1]. The AIDA collaboration comprises two independent spacecraft, the NASA-sponsored Double Asteroid Redirection Test (DART) and the ESA-led Hera. In September 2022 the DART spacecraft will impact the secondary member of the binary asteroid system 65803 Didymos (Didymos-B) at a speed of ~6.7 km/s and mass ~500 kg. The resulting period change in the orbit of Didymos-B will be measured using Earth-based observations. Hera will arrive post-impact and perform detailed measurements to characterize Didymos-B.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"45 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72986388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
For the numerical description of high velocity impact, Smooth-Particle-Hydrodynamics (SPH) has gained more and more interest. The standard Lagrangian Finite-Element (FE) approach has difficulties in describing large deformations and fracture. However, a simulation based on SPH only is very expensive due to the small size of the particles. A well adopted solution to this is to couple both methods, using SPH only where it is necessary, and capturing the outer boundary conditions with a bias FE-mesh correctly - without considerable extra computational cost. We apply such a hybrid approach in LS-DYNA® for the characterization of threats in terminal ballistics. Different meshing approaches for the projectile and target were implemented to guarantee an optimal initial condition. The particle size and the required size of the SPH-region were studied to exclude discretization effects. Exemplarily, a projectile surrogate with simplified geometry is investigated for a fixed impact velocity and two different angles of obliquity. A qualitative comparison between experiments, observed with X-ray cinematography, reveals a good potential of this approach towards predicting fracture and ricochet during high velocity impact events.
{"title":"Automatic Mesh-Generation (FEM/SPH) for HVI-Simulations of Arbitrary Rotational Symmetric Impactors","authors":"Marvin Becker, M. Seidl, M. Mehl, M. Souli","doi":"10.1115/hvis2019-080","DOIUrl":"https://doi.org/10.1115/hvis2019-080","url":null,"abstract":"\u0000 For the numerical description of high velocity impact, Smooth-Particle-Hydrodynamics (SPH) has gained more and more interest. The standard Lagrangian Finite-Element (FE) approach has difficulties in describing large deformations and fracture. However, a simulation based on SPH only is very expensive due to the small size of the particles. A well adopted solution to this is to couple both methods, using SPH only where it is necessary, and capturing the outer boundary conditions with a bias FE-mesh correctly - without considerable extra computational cost.\u0000 We apply such a hybrid approach in LS-DYNA® for the characterization of threats in terminal ballistics. Different meshing approaches for the projectile and target were implemented to guarantee an optimal initial condition. The particle size and the required size of the SPH-region were studied to exclude discretization effects. Exemplarily, a projectile surrogate with simplified geometry is investigated for a fixed impact velocity and two different angles of obliquity. A qualitative comparison between experiments, observed with X-ray cinematography, reveals a good potential of this approach towards predicting fracture and ricochet during high velocity impact events.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"229 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75018195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This work investigates the importance of the microstructure of boron carbide for initiating inelastic deformation under impact conditions. Simple loading resulting from a flyer plate impact geometry is used to illustrate the importance of microstructure for the well-controlled and easily instrumented experimental geometry. A second set of simulations is performed on a miniaturized impact geometry to investigate the importance of the microstructure for the early stages of semi-infinite penetration for impact velocities between 0.9 km/s and 1.9 km/s. The effect of the microstructure is more pronounced for the flyer plate impact geometry.
{"title":"The Role of Inclusions in the Failure of Boron Carbide Subjected to Impact Loading","authors":"A. Tonge, B. Schuster","doi":"10.1115/hvis2019-056","DOIUrl":"https://doi.org/10.1115/hvis2019-056","url":null,"abstract":"\u0000 This work investigates the importance of the microstructure of boron carbide for initiating inelastic deformation under impact conditions. Simple loading resulting from a flyer plate impact geometry is used to illustrate the importance of microstructure for the well-controlled and easily instrumented experimental geometry. A second set of simulations is performed on a miniaturized impact geometry to investigate the importance of the microstructure for the early stages of semi-infinite penetration for impact velocities between 0.9 km/s and 1.9 km/s. The effect of the microstructure is more pronounced for the flyer plate impact geometry.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79117885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Hawkins, S. A. Thomas, R. Hixson, Nan Li, S. Fensin
A series of shock loading experiments were conducted on High Entropy Alloy (HEA) samples consisting of Fe/Cr/Mn/Ni in weight percentages of 25.2/23.5/24.8/26.5. Characterizing this transition metal alloy is a first step in understanding the shock compression response of this relatively new class of alloy. A single stage light gas gun was used to conduct a series of flyer plate symmetric impact experiments to obtain fundamental dynamic properties. Photonic Doppler Velocimetry (PDV) diagnostics were employed to measure the free surface velocity on the back of each target during dynamic compression. These experiments yielded four data points that are in reasonable agreement with an estimated Hugoniot for the material.
{"title":"High velocity impact of an Fe/Cr/Mn/Ni high entropy alloy","authors":"M. Hawkins, S. A. Thomas, R. Hixson, Nan Li, S. Fensin","doi":"10.1115/hvis2019-008","DOIUrl":"https://doi.org/10.1115/hvis2019-008","url":null,"abstract":"\u0000 A series of shock loading experiments were conducted on High Entropy Alloy (HEA) samples consisting of Fe/Cr/Mn/Ni in weight percentages of 25.2/23.5/24.8/26.5. Characterizing this transition metal alloy is a first step in understanding the shock compression response of this relatively new class of alloy. A single stage light gas gun was used to conduct a series of flyer plate symmetric impact experiments to obtain fundamental dynamic properties. Photonic Doppler Velocimetry (PDV) diagnostics were employed to measure the free surface velocity on the back of each target during dynamic compression. These experiments yielded four data points that are in reasonable agreement with an estimated Hugoniot for the material.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"36 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79798054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Davis, Richard A. Hagen, Robert J. McCandless, E. Christiansen, D. M. Lear
NASA, JSC has been developing a light-weight, multi-functional sandwich core for habitable structure over the last several years. Typically honeycomb-based structures have been and still are a common structural component for many applications in the aerospace industry, unfortunately, honeycomb structures with an ordered, open path through the thickness have served to channel the micro-meteoroid or orbital debris into the pressure wall (instead of disassociating and decelerating). The development of a metallic open cell foam core has been explored to enhance the micro-meteoroid or orbital debris protection, which is heavier than comparable honeycomb-based structures when non-structural requirements for deep space environments (vacuum, micro-meteoroids/orbital debris, and radiation) have not been considered. While the metallic foam core represents a notable improvement in this area, there is an overwhelming need to further reduce the weight of space vehicles; especially when deep space (beyond low earth orbit, or LEO) is considered. NASA, JSC is currently developing a multi-functional sandwich panel using additive machining (3D printing), this effort evaluated the material response of a limited amount of 3D printed aluminum panels under hypervelocity impact conditions. The four 3D printed aluminum panels provided for this effort consisted of three body centric cubic lattice structure core and one kelvin cell structure core. Each panel was impacted once with nominally the same impact conditions (0.34cm diameter aluminum sphere impacting at 6.8 km/s at 0 degrees to surface normal). All tests were impacted successfully, with the aforementioned impact conditions. Each of the test panels maintained their structural integrity from the hypervelocity impact event with no damage present on the back side of the panel for any of the tests. These tests and future tests will be used to enhance development of 3D printed structural panels.
{"title":"Hypervelocity impact performance of 3D printed aluminum panels","authors":"B. Davis, Richard A. Hagen, Robert J. McCandless, E. Christiansen, D. M. Lear","doi":"10.1115/hvis2019-055","DOIUrl":"https://doi.org/10.1115/hvis2019-055","url":null,"abstract":"\u0000 NASA, JSC has been developing a light-weight, multi-functional sandwich core for habitable structure over the last several years. Typically honeycomb-based structures have been and still are a common structural component for many applications in the aerospace industry, unfortunately, honeycomb structures with an ordered, open path through the thickness have served to channel the micro-meteoroid or orbital debris into the pressure wall (instead of disassociating and decelerating). The development of a metallic open cell foam core has been explored to enhance the micro-meteoroid or orbital debris protection, which is heavier than comparable honeycomb-based structures when non-structural requirements for deep space environments (vacuum, micro-meteoroids/orbital debris, and radiation) have not been considered. While the metallic foam core represents a notable improvement in this area, there is an overwhelming need to further reduce the weight of space vehicles; especially when deep space (beyond low earth orbit, or LEO) is considered. NASA, JSC is currently developing a multi-functional sandwich panel using additive machining (3D printing), this effort evaluated the material response of a limited amount of 3D printed aluminum panels under hypervelocity impact conditions. The four 3D printed aluminum panels provided for this effort consisted of three body centric cubic lattice structure core and one kelvin cell structure core. Each panel was impacted once with nominally the same impact conditions (0.34cm diameter aluminum sphere impacting at 6.8 km/s at 0 degrees to surface normal). All tests were impacted successfully, with the aforementioned impact conditions. Each of the test panels maintained their structural integrity from the hypervelocity impact event with no damage present on the back side of the panel for any of the tests. These tests and future tests will be used to enhance development of 3D printed structural panels.","PeriodicalId":6596,"journal":{"name":"2019 15th Hypervelocity Impact Symposium","volume":"84 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86570495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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