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Abstrak :
Shape Memory Alloy (SMA) merupakan suatu material cerdas yang memiliki kemampuan ingat bentuk (Shape Memory Effect). SMA dapat kembali ke bentuk semula setelah mengalami deformasi dan diberi perlakuan panas karena terjadi perubahan fasa dari detwinned martensite ke fasa awal austenite karena sifatnya, SMA dapat diaplikasikan pada berbagai bidang, terutama pada bidang medis dan otomotif. Penelitian ini menjelaskan pengaruh dari temperatur terhadap karakteristik dan waktu pemulihan yang dimiliki oleh kawat NiTi dan NiTiCu dengan variasi temperatur 30C, 200C, dan 600C dan beban sebesar 10 g, 30 g, 50 g, dan 100 g yang bertujuan untuk mendapatkan suatu persentase pemulihan dalam waktu 1 menit. Karakterisasi yang digunakan pada penelitian kali ini dengan menggunakan pengujian XRD dan Shape Memory Testing (SMT). Secara umum, persentase pemulihan pada kawat NiTiCu lebih baik dibandingkan kawat NiTi yang dikarenakan adanya penambahan unsur ketiga dari paduan NiTi berupa tembaga (Cu). Selain itu, peningkatan temperatur pada NiTi dan NiTiCu juga meningkatkan persentase pemulihan yang digunakan pada pengujian berbagai variasi beban dan pengujian berulang. Kemudian, hasil yang didapatkan dari persentase pemulihan tertinggi sebesar 48% yang didapatkan pada NiTiCu dan NiTi dengan temperatur forming 600C pada pembebanan 10 gram. Sedangkan persentase pemulihan terendah sebesar 6% yang didapatkan pada NiTi dengan temperatur normal 30C pada pembebanan 100 gram. ......Shape Memory Alloy (SMA) is a smart material that has the ability to remember shapes (Shape Memory Effect). SMA can return to its original shape after being deformed and given heat treatment due to a phase change from detwinned martensite to the initial austenite phase. Because of its nature, SMA can be applied in various fields, especially in the medical and automotive fields. This study describes the effect of temperature on the characteristics and recovery time of NiTi and NiTiCu wires with temperature variations of 30C, 200C and 600C and loads of 10 g, 30 g, 50 g and 100 g which aims to obtain a percentage of recovery in 1 minute time. The characterization used in this study uses XRD and Shape Memory Testing (SMT) testing. In general, the recovery percentage of NiTiCu wire is better than NiTi wire due to the addition of a third element of the NiTi alloy in the form of copper (Cu). In addition, increasing the temperature of NiTi and NiTiCu also increases the percentage of recovery used in testing various load variations and repeated tests. Then, the results obtained from the highest recovery percentage of 48% were obtained for NiTiCu and NiTi with a forming temperature of 600C at a loading of 10 grams. While the lowest recovery percentage of 6% was found in NiTi with a normal temperature of 30C at a loading of 100 grams.

Abstrak :
The SMST Conferences focus on real-world issues and applications of shape memory materials. This volume includes more than 75 edited technical papers and is an excellent reference on the latest technical advances, industrial applications, and current state-of-the-art in shape memory and superelastic technologies.

Abstrak :
The SMST Conferences focus on real-world issues and applications of shape memory materials. This volume includes more than 100 edited technical papers and is an excellent reference on the latest technical advances, industrial applications, and current state of-the-art in shape memory and superelastic technologies.

Abstrak :
Edited by B. Berg, M.R. Mitchell, J. Proft Audience Engineers and researches involved in the application and study of shape memory and superelastic technologies.

Abstrak :
Perkembangan teknologi 3D print telah merevolusi bidang rekayasa jaringan dalam manufaktur scaffold dengan struktur yang kompleks. Penggunaan poly-lactic acid (PLA) sebagai bahan dasar scaffold telah umum digunakan karena sifatnya yang biokompatibel dan bioresorbable. Di sisi lain, PLA memiliki sifat unik berupa shape memory effect (SME) sehingga membuka peluang dalam pengembangan self-fitting scaffold. Namun, permukaan PLA yang bersifat hidrofobik menghambat interaksi scaffold dengan jaringan sekitar. Sebagai upaya untuk meningkatkan hidrofilisitas permukaan, scaffold PLA dilakukan modifikasi permukaan menggunakan alkali treatment dan pelapisan hidroksiapatit (HAp). Hidroksiapatit merupakan utama penyusun tulang sehingga diharapkan mampu meningkatkan fungsi biologis scaffold. Untuk mengetahui konsentrasi pelapisan HAp yang optimal dilakukan variasi konsentrasi HAp dalam dispersi HAp-etanol sebesar 0,5, 1, dan 2% (w/v). Pengaruhnya terhadap SME dan bioaktivitas scaffold PLA akan dievaluasi menggunakan uji imersi r-SBF, observasi visual, uji kompresi, dan karakterisasi SEM-EDS. Hasil uji imersi menunjukkan bahwa pemberian dan peningkatan konsentrasi HAp pada permukaan mampu meningkatkan kemampuan absorpsi air scaffold secara signifikan. Selain itu, scaffold juga terukur mengalami tren peningkatan massa selama pengujian. Observasi visual menunjukkan adanya kristal putih terpresipitasi. Melalui karakterisasi SEM-EDS diketahui komposisi kristal yang terbentuk adalah CaP. Dengan demikian, dapat diketahui bahwa peningkatan konsentrasi lapisan HAp akan meningkatkan bioaktivitas scaffold melalui peningkatan laju presipitasi CaP. Namun, hal ini juga akan berdampak pada penurunan kekuatan kompresi serta kemampuan strain recovery akibat adanya penetrasi HAp ke dalam scaffold sehingga mengalami aglomerasi dan menyebabkan terjadinya embrittlement pada scaffold. ......The development of 3D printing technology has revolutionized the field of tissue engineering in manufacturing scaffolds with complex structures. The use of poly-lactic acid (PLA) as the base material for scaffolds has been widely adopted due to its biocompatible and bioresorbable properties. However, PLA has a unique property known as shape memory effect (SME), which opens up opportunities for the development of self-fitting scaffolds. On the other hand, the hydrophobic nature of PLA surfaces inhibits the interaction between the scaffold and the surrounding tissue. In an effort to enhance the hydrophilicity of the surface, surface modifications are performed on PLA scaffolds using alkali treatment and hydroxyapatite (HAp) coating. Hydroxyapatite, being the main component of bone, is expected to improve the biological function of the scaffold. To determine the optimal concentration of HAp coating, variations in HAp concentration in the HAp-ethanol dispersion are conducted at 0.5%, 1%, and 2% (w/v). Their influence on the SME and bioactivity of the PLA scaffold will be evaluated using r-SBF immersion tests, visual observations, compression tests, and SEM-EDS characterization. The immersion test results show that the addition and increased concentration of HAp on the surface significantly enhance the water absorption capacity of the scaffold. Additionally, the scaffold's measured mass shows an increasing trend during the testing. Visual observations reveal the presence of white crystals that precipitate. Through SEM-EDS characterization, it is determined that the composition of the formed crystals is CaP. Thus, it can be concluded that increasing the concentration of the HAp layer enhances the scaffold's bioactivity by increasing the rate of CaP precipitation. However, this also leads to a decrease in compressive strength and strain recovery ability due to HAp penetration into the scaffold, causing agglomeration and resulting in scaffold embrittlement.

Abstrak :
The SMST Conferences are a series of shape memory industry conferences focusing on real-world issues and applications of shape memory materials. Each volume of the proceedings contains over 100 technical papers and is an excellent reference on the current state-of-the-art in the shape memory and superelastic industry. Topics covered include Medical and Dental Applications, Biocompatibility, Corrosion, Actuators, Connectors, Alloy Processing, Manufacturing Issues, Laser Processing, Design, Finite Element Analysis, and Shape Memory Thin Films.