Ballistic Limit of CFRP Plates

The influence of target span as well as configuration was studied with 1 mm thick 1100H12 aluminum target subjected to19 mm diameter ogive nosed projectile impact. The effective span of 1 mm thick monolithic target was varied as 95, 190, 285, 380 and 475 mm. The configuration of 255 mm span diameter target was varied as 1 mm thick monolithic, double layered in-contact (2 x 0.5 mm) and double layered spaced. The spacing between the layers was also varied as 2, 5, 10 and 20 mm. The target was impacted normally by ogive nosed projectile to obtain the ballistic limit, failure mode and deformation. The ballistic limit was found to increase with an increase in span diameter. The monolithic target offered highest ballistic limit followed by layered in-contact and spaced targets respectively. The variation of spacing between the layers did not have significant influence on the ballistic limit.

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Predicting Ballistic Penetration and the Ballistic Limit in Composite Material Structures

AIAA Journal ◽

10.2514/2.1578 ◽

2002 ◽

Vol 40 (11) ◽

pp. 2366-2368 ◽

Cited By ~ 3

Author(s):

Jeffrey R. Focht ◽

Jack R. Vinson

Keyword(s):

Composite Material ◽

Ballistic Limit ◽

Ballistic Penetration

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Numerical modeling of high velocity impact in sandwich panels with honeycomb core and composite skin including composite progressive damage model

Journal of Sandwich Structures & Materials ◽

10.1177/1099636218817894 ◽

2018 ◽

Vol 22 (8) ◽

pp. 2768-2795 ◽

Cited By ~ 3

Author(s):

Meysam Khodaei ◽

Mojtaba Haghighi-Yazdi ◽

Majid Safarabadi

Keyword(s):

Numerical Model ◽

Sandwich Panel ◽

Material Model ◽

Absorption Capacity ◽

Numerical Results ◽

Ballistic Impact ◽

Experimental Results ◽

Ballistic Limit ◽

Honeycomb Core ◽

Damage Initiation

In this paper, a numerical model is developed to simulate the ballistic impact of a projectile on a sandwich panel with honeycomb core and composite skin. To this end, a suitable material model for the aluminum honeycomb core is used taking the strain-rate dependent properties into account. To validate the ballistic impact of the projectile on the honeycomb core, numerical results are compared with the experimental results available in literature and ballistic limit velocities are predicted with good accuracy. Moreover, to achieve composite skin material model, a VUMAT subroutine including damage initiation based on Hashin’s seven failure criteria and damage evolution based on MLT approach modulus degradation is used. To validate the composite material model VUMAT subroutine, the ballistic limit velocities of the projectile impact on the composite laminates are predicted similar to the numerical results presented by other researchers. Next, the numerical model of the sandwich panel ballistic impact at different velocities is compared with the available experimental results in literature, and energy absorption capacity of the sandwich panel is predicted accurately. In addition, the numerical model simulated the sandwich panel damage mechanisms in different stages similar to empirical observations. Also, the composite skin damages are investigated based on different criteria damage contours.

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Ballistic Limit Estimation Approaches for Ballistic Resistance Assessment

Defence Science Journal ◽

10.14429/dsj.70.14122 ◽

2020 ◽

Vol 70 (1) ◽

pp. 82-89

Author(s):

Beya Tahenti ◽

Frederik Coghe ◽

Rachid Nasri

Keyword(s):

Extreme Values ◽

Impact Testing ◽

Estimation Methods ◽

Experimental Sample ◽

Ballistic Limit ◽

Ballistic Resistance ◽

Limit Velocity ◽

Resistance Assessment ◽

Ballistic Limit Velocity ◽

Set Up

The armour technologist conducts ballistic impact testing either for evaluating armour materials and systems or for studying material’s defeating mechanism. Most standards make use of the ballistic limit velocity for ballistic assessment. This is the bullet impact velocity that leads to the protection perforation in 50 per cent of the cases. Various models have been emerged to estimate this key metric. The present article summarises the popular models developed for ballistic limit estimation. An attempt is made to point out models’ strength and weakness. First, the experimental set-up used for that goal is displayed. Next, a concise overview of ballistic limit estimation methods is presented. Lastly, a discussion is dedicated to model’s comparison and analysis. This literature survey reveals that the main drawback of already existing methods is that they are purely statistical. Moreover, existing methods are based on the normality assumption of perforation velocities which tends from -infinity to infinity. The main conclusion of this survey is that the presented methods offer a comparable accuracy in estimating the ballistic limit velocity. However, a given variability is remarked when extreme values estimation is of interest, impact velocities leading to low and high perforation probability. Finally, existing models’ performances decay with the reduction of the experimental sample size which represent a constraining requirement in ballistic resistance assessment.

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