Collimator is a tube that functions to direct neutrons generated by a nuclear reactor for BNCT (Boron Neutron Capture Therapy Cancer). Appropriate design of the collimator for BNCT application is a tube with an inner diameter of 16 cm, an outer diameter of 19 cm and a length of 13 cm total with 12 pieces with nickel purity above 95%. Manufacturing of the BNCT collimator will be planned using centrifugal casting method and smelting of nickel with electrical arc (EA) furnace. This article reports on the smelting process of nickel, setting the parameters of the electrical arc furnace, and the chemical composition of the nickel. Results of the study show that nickel with purity 98% can be melted perfectly using the EA Furnace with a current of 600-800 A and a pouring temperature of 1600°C. The fluidity of nickel can hold up to 1 minute at a 35°C environment that allows for the centrifugal casting process. The chemical composition of the nickel before being melted is Ni (98.89%), Si (0.79%), S (0.17%), and Fe (0.15%) and after being melted is Ni (97.89%), Si (0.92%), S (0.26%), and Fe (0.90%). The chemical composition of the nickel after smelting in an EA Furnace meets the requirements of BNCT collimator.

Multilayer armour system (MAS) becomes the best choice in reinforcing protection for military officers against projectile attack which has a high velocity of up to 7.62×51 mm NATO ball lead core (projectile level III NIJ standard) or AP 7.62×51 mm hard steel core (projectile level IV NIJ standard). This study aimed to analyze the damage formation of wolfram carbide (WC) ceramic and ramie fiber composites. The frontmost MAS uses WC ceramic and is enveloped by a back layer of ramie fiber composites with epoxy resin reinforcing material as the matrix. Ballistic testing was carried out in this study using a long-barreled rifle to determine the resistance of the MAS from projectile impact. The speed meter in ballistic testing uses a velocity sensor type light screen B 471 and clay witness is used to measure back face signature (BFS). The results show that 7.62 lead core and hard steel core projectiles were unable to penetrate the 3-layer ceramic MAS in the front. The results are marked by a relatively low BFS value of 1.45 and 1.17 mm, so that the energy in the MAS with 3 ceramic layer is absorbed efficiently but with the phenomenon of rupture ceramic failure. Ceramic rupture failure needs to be overcome by bonding several layers of ramie so that MAS can be used in the next stage. MAS with 1 and 2 ceramic layers are unable to withstand projectile level III and level IV NIJ standard. From these results it is known that the MAS limit can withstand the projectile level III and IV NIJ standard, namely MAS with 3 ceramic layers. The damage formation of ceramic was rupturing ceramic failure. Therefore, it is necessary to design a ceramic binder by placing some ramie fibers in front of the ceramic

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This research is a preliminary study to determine the feasibility of the ballistic test equipment using fragment-simulating projectiles (FSP) and the ability of the rami-epoxy composite against bullet penetration. Tests have been conducted in which FSP were fired at epoxy ramie composites. Ballistic test equiment was equipped with a chronograph and high speed camera. The composites were manufactured using manual hand lay-up compression moulding 60% volume fraction. Based on the high speed camera result shows that the FSP projectile when crashing into the specimen was not in perfect position (tilted) and the ramieepoxy composite was fail in 6, 9, and 12 layers.