Rapid Prototyping (RP) is a method used everywhere from the entertainment industry to healthcare. Layer orientation is an important aspect of the final product. The objective of this research was to evaluate the effect of layer orientation on the mechanical strength and toughness of a polymer. The polymer used was a combination of two materials, ZP 130 and ZB 58, fused together in the Z Corporation Spectrum Z510 Rapid Prototyping Machine. ZP 130 is a powder composed of vinyl polymer (2-20%), sulfate salt (0-5%), and plaster that contains <1% crystalline silica (50-95%). ZB 58 is a liquid composed of glycerol (1-10%), preservative (sorbic acid salt) (0-2%), surfactant (<1%), pigment (<1%), and water (85-95%). After removal from the machine the samples were sealed with Z bond 101 which is Beta-methoxyethyl cyanoacrylate (60-100%). The layer orientations studied were the crack arrestor, crack divider, and short transverse with various combinations of the three, for a total of seven orientations. The mechanical strength was evaluated using tensile testing and three-point bend testing. The toughness was evaluated by Izod impact testing. Five samples for tensile testing and three-point bend testing as well as 15 samples for the Izod impact test for each of the seven orientations were made. The total number of samples was 175. The crack arrestor orientation was the strongest main orientation for the tensile and three-point bend test. Weibull analysis was done on the Izod impact testing due to high variation in the results for the crack arrestor and short transverse directions. It was found that the layer orientation and surface roughness played a significant role in the penetration of the Z bond 101 coating and in the overall strength of the samples.

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Pengujian getaran terhadap head expander telah dilaksanakan. Pengujian ini bertujuan untuk mengetahui karakteristik dinamis dari head expander yang digunakan pada Laboratorium Uji Suhu dan Vibrasi Pusat Teknologi Penerbangan-LAPAN. Head expander digunakan sebagai alat bantu pengujian untuk kebutuhan benda uji yang besar. Validasi head expander melalui metode eksperimental ini bertujuan untuk mengetahui tingkat homogenitas head expander. Pengambilan data menggunakan 4 buah akselerometer yang ditempatkan pada setiap ujung head expander. Getaran sine sweep diberikan mulai dari 5 Hz sampai 2000 Hz dengan amplitude konstan sebesar 1g dan sweep rate sebesar 1 octave/minute. Hasil pengujian menunjukkan bahwa head expander memiliki sifat homogen dengan nilai frekuensi alami yang tidak berbeda jauh.

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