• Journal of the Korean Society of Propulsion Engineers
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• v.21 no.4
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• pp.96-106
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• 2017

In pressable polymer bonded explosives (PBXs), densification occurs due to rearrangement and deformation of explosive particles during pressing. If brittle explosives are compressed till particle fraction become higher than theoretical random close packing fraction (RCPF), bigger particles should be fractured to fill the void. In this study, multi-modal particle system was introduced for the decrease in possibility of particle fracture during compression expecting decrease in shock sensitivity of highly filled pressable PBX. The experimental results showed the trimodal particle system had low sensitivity with high density, compared to bimodal particle system.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.462-468
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• 2017

KYP model is a pressure-based chemical kinetics that describes shock to detonation transition of energetic materials. In this research, the parameters of KYP model and JWL EOS for PETN-based explosive, namely PBXN-301, were determined. A series of unconfined rate stick tests and two dimensional hydrodynamic simulation were conducted to obtain the size effect behaviour of the explosive. As a result, it was confirmed that the parameters obtained from KYP modeling have more accuracy to predict the detonation velocities according to the inverse radius of PBXN-301 than the qualitatively obtained LLNL constitutive equations.

• Korean Chemical Engineering Research
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• v.44 no.5
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• pp.435-443
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• 2006

The objective of this paper is to provide fundamental information on the subject of high explosives not only to the explosive scientist but also to the chemical engineer. Technologies for the development of high explosives are divided into 5 areas: (1) synthesis of new energetics, (2) preparation of functional explosives, (3) formulation study of plastic bonded explosives, (4) application of high explosives to munitions, (5) demilitarization process. This paper outlines the basic technologies need to understand the high explosives.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.6
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• pp.397-404
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• 2019

Linear Shaped Charge (LSC) that is widely used as separation system in aerospace system has to charge lots of explosives due to lack of uniformity. In addition, it is hard to optimize shape of liner and explosives because of manufacturing process. In order to overcome aforementioned drawbacks, Precision Linear Shaped Charge (PLSC) is currently under development. PLSC is made in two steps: prepare liner independently and charge explosive uniformly. In this study, PLSC is designed to have proper amount of explosives and penetration test of PLSC with different stand-off distance from liner to target is conducted to confirm penetration performance. Based on the penetration test results of PLSC, the numerical analysis method using AUTODYN is established and verified. Penetration mechanism and characteristics of PLSC is analyzed from the numerical and experimental results.

• Journal of the Korean Society of Propulsion Engineers
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• v.20 no.5
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• pp.40-50
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• 2016

Energetic plasticizers containing explosophore groups such as $-NO_2$, $-ONO_2$, and $-N_3$ group are susceptible to impact, shock, heat, etc, finally deteriorating the insensitivity of PBXs. In this study, in an attempt to investigate the feasibility of replacing sensitive explosophore groups to fundamentally inactive but potentially (latent) energetic fluorine group which was known to have an exothermic thermite reaction with aluminum, nano-aluminum/fluorinated polyurethane binders were prepared by simultaneous polyurethane and catalyst-free azide-alkyne click reaction in the presence of nano-aluminum. Thermal characteristics of nano-aluminum/fluorinated polyurethane binders were monitored by using DSC with high pressure crucible pan.

• Proceedings of the KSEE Conference
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• 2007.03a
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• pp.159-166
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• 2007

• Journal of the Korea Institute of Military Science and Technology
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• v.4 no.1
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• pp.20-29
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• 2001

We recently developed a friability test procedure, which will be used as one of substance tests for Extremely Insensitive Detonating Substances(EIDSs) in Test Series 7 of the United Nations. This test was intended to assess the susceptibility of insensitive explosives to the break-up as high strain rate and subsequent ignition characteristics of the deformed material. We designed an air gun system using the hydro code simulation. The projectile velocities of the gun were in good agreement with those predicted by the hydro code with an inert material. Three different types of explosives, melt castable Comp B, castable plastic bonded explosives(PBXs), and pressable PBXs were tested during the development of the test procedure. Two tastable PBXs, i.e. DXD-09 and DXD-10, which are currently under development as candidate formulations of EIDS were classified as EIDS, since test results with these formulations were far better than the criterion of the UN Test Series 7.

• Defense and Technology
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• no.2 s.276
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• pp.30-39
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• 2002

화공기술이란 연소와 폭발성을 갖는 단일 또는 복합 물질을 기제로 하여 제품을 사용 목적에 맞도록 제조와 응용하는 기술을 의미하며, 화약의 에너지 물질로서 제조된 다양한 제품을 화공품(Pyrotechnics)이라고 한다. 우리 주변에서 흔히 볼 수 있는 것은 산업용으로 성냥, 딱총약, 엽총화약, 연화, 광산용의 도화선, 도폭선, 각종 뇌관류 등이 있고, 군용으로는 발사화기와 로케트 추진기관의 점화계열, 탄두/탄약의 폭발계열, 신호탄, 연막, 조명탄 등을 들 수 있다.

• Journal of the Korea Institute of Military Science and Technology
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• v.7 no.2 s.17
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• pp.100-108
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• 2004

Nitramine-polymer composites suffer from a problem known as dewetting. Dewetting adversely affects the performance and the sensitivity characteristics of an explosive composition. Voids, which are generated between explosive particles and binder on dewetting, act as initiation sites. For a PBXs as well as propellants, where good adhesion and mechanical properties are of great importance, dewetting therefore must be prevented by strong adhesion between the filler and the binder. The surface energy of materials is measured by Wilhelmy plate and wicking method. The interfacial energy between the filler and the binder is calculated from the disperse phase and the polar phase of surface energy. Time dependent compressive properties of composite explosives have been determined by stress-strain curves obtained at different strain rates and temperatures. The interfacial state of the PBX was observed through SEM. It was found from the result that the interface between the explosive and the binder becomes better adhesion with decreasing interfacial tension and increasing work of adhesion. The result clearly shows that the castable PBX has good adhesion more than the pressable PBX.

• Explosives and Blasting
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• v.22 no.1
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• pp.45-56
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• 2004

The industrial explosives in Korea have been made and used since 1952. The blasting accidents have increased gradually with the use of explosives. Based on the Police Department and Guns & Explosives Safety Technology Association's researching materials, the blasting accidents between 1988 and 1997 have been investigated and analyzed in this paper. FTA method was applied for the analysis of the blasting accidents which occurred in the tunnels, roads, subways, and various kinds of building construction area. The results show that the majority of the accidents, about 45.7% of the total, are due to the fly rocks. It is similar trend in Japan. The FTA analysis performed on the accidents by fly rocks shows that the major source of the accident is human factors such as non-observance of the safety rules, less knowledge of the safety and so on. The results of the study ate expected to provide basic data for making and observing the safety rules, making and amending the laws concerned and planning the security project. It will be helpful in preventing the blasting accidents and in reducing the loss of valuable lives and the financial damage.