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"Paduan ingat bentuk merupakan kelompok paduan yang memiliki karakteristik unik untuk mengingat dan kembali ke bentuk semula setelah diberikan tegangan dan terdeformasi dengan cara di panaskan pada temperatur tertentu. Salah satu jenisnya ialah, paduan berbasis Cu yang memiliki sifat ingat bentuk yang baik dan bisa digunakan sebagai alternatif karena biayanya yang murah dibandingkan jenis paduan lainnya. Pada penelitian ini dipelajari pengaruh metode pencelupan terhadap sifat ingat bentuk paduan Cu-24,12Al-3,13Mn (%Atomik) yang dibuat berdasarkan metode pengecoran gravitasi yang selanjutnya dihomogenisasi pada temperatur 900 °C selama 2 jam dan didinginkan pada temperatur ruang. Setelah paduan mencapai temperatur ruang, dilakukan perlakuan panas betatizing pada temperatur 900 °C selama 30 menit dan dilanjutkan dengan tiga metode pencelupan yang berbeda, yaitu Pencelupan Langsung (Direct Quench/DQ), Pencelupan Bertahap (Step Quench/SQ), dan Pencelupan Naik (Up Quench/UQ). Tahapan selanjutnya ialah melakukan karakterisasi paduan yang dilakukan mengunakan Optical Microscope (OM), Scanning Electron Microscopy and Energy Dispersive X-Ray Spectroscopy (SEM-EDS), X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), Bending Test, dan Microvickers. Hasil penelitian ini menyatakan bahwa, paduan As-Cast dan As-Homogenizedterdiri atas fasa b [BCC] yang memiliki morfologi acicular (b acicular) atau b [B2] Acicular dan fasa g yang terbentuk seperti nodular-nodular hitam di sekitar matriks. Pencelupan DQ menghasilkan fasa b' [M18R] dan fasa g untuk pencelupan UQ dan SQ menghasilkan fasa b' [M18R] dan fasa b [B2] Acicular dengan nilai SME berturut-turut adalah 32,43% (DQ), 10,75% (UQ), dan 9,10% (SQ). Sementara, nilai kekerasan berturut-turut adalah 233,49 HVN (SQ), 222,20 HVN (UQ), dan 20,72 (DQ). Hal ini menunjukkan bahwa indikasi dari adanya sifat Shape Memory Effect dikontribusi oleh keberadaan fasa martensit b' [M18R].

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Shape Memory Alloys are a group of alloys that have the unique characteristics to remember their original shape after deformation followed by heating at a certain temperature. Cu-based alloys have good shape memory effect properties and can be used as an alternative because of the low cost compared to the other types of SMA alloy. This research studied the effect of the quenching methods on the martensite phase transformation and shape memory properties of the Cu-24,12Al-3,13Mn alloy (% atomic). The alloy was by gravity casting and was homogenized at 900 °C for 2 hours and cooled to room temperature. The betatizing treatment was carried out at a temperature 900 °C for 30 minutes and subsequently quenched with three methods, Direct Quench (DQ), Step Quench (SQ), and Up Quench (UQ). Characterization was conducted by Optical Microscope (OM), Scanning Electron Microscopy and Energy Dispersive X-Ray Spectroscopy(SEM-EDS), X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), Bending Test, and Microvickers. The results showed that, the as-cast and as-homogenized alloy consisted of b [BCC] phase with acicular morphology (bacicular) or b [B2] Acicular and g phase, which formed as small black-nodular. The DQ microstructures showed b'[M18R] phase and g phase, with the UQ and SQ microstructures consisted of b' [M18R] phase dan b [B2] Acicular, The Shape Memory Effect values of DQ, UQ, and SQ samples were 32,43%, 10,75%, and 9,10% while the hardness were 207,72 HVN, 222,20 HVN, 233,49 HVN. This indicates that the shape memory properties contributed by the formed of phase martensite b' [M18R] in this alloy. "

"Paduan ingat bentuk merupakan salah satu material cerdas yang memiliki karakteristik unik dimana paduan ini dapat mengingat bentuk saat diberi panas. Paduan ingat bentuk yang berbasis Cu merupakan alternatif yang paling baik dikarenakan harganya yang murah dan memiliki sifat ingat bentuk yang baik. Penelitian ini mempelajari pengaruh metode pencelupan terhadap transformasi fasa dan kekerasan paduan Cu-26.5Al-3.7Mn (%Atomik) yang difabrikasi menggunakan metode pengecoran gravitasi. Paduan dihomogenisasi pada temperatur 900 ? selama 2 jam. Selanjutnya dilakukan perlakuan panas betatizing pada temperatur 900 ? selama 30 menit dan dilanjutkan dengan tiga metode pencelupan yang berbeda, yaitu Pencelupan Langsung (DQ), Pencelupan Naik (UQ), dan Pencelupan Bertahap (SQ). Karakterisasi menggunakan Optical Microscope (OM), Scanning Electron Microscopy dan Energy Dispersive X-Ray Spectroscopy (SEM-EDX), Optical Emission Spectroscopy (OES), X-Ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), Microvickers, dan uji pemulihan regangan. Hasil penelitian menunjukkan bahwa struktur mikro paduan pada kondisi As-Cast dan As-Homogenized terdiri dari dua fasa yaitu ? [D03] dan ? dengan morfologi rosette-like. Pencelupan DQ dan UQ menghasilkan martensit ?' dan ? [D03] sisa, sementara pencelupan SQ selain menghasilkan fasa tersebut juga terdapat ?. Selanjutnya, nilai kekerasan adalah 288,71 HVN (As-cast), 300,21 HVN (As-Homogenized), 232,2 HVN (DQ), 240,1 HVN (UQ), dan 289 HVN (SQ). Persentase pemulihan regangan tidak dapat diukur dikarenakan sampel patah saat ditekuk.

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The shape memory alloy is a smart material with unique characteristics where it can remember its shape when subjected to heat. Cu-based shape memory alloys are considered the most favorable alternative due to their low cost and good shape memory properties. In this study, the influence of quenching methods on phase transformation and hardness of Cu-26.5Al-3.7Mn (at. %) alloy fabricated using gravity casting method was investigated. The alloy was homogenized at 900 ? for 2 hours, and then betatized at 900 ? for 30 minutes, followed by three different quenching methods: Direct Quenching (DQ), Up Quenching (UQ), and Step Quenching (SQ). The alloy was then characterized using Optical Microscope (OM), Scanning Electron Microscopy and Energy Dispersive X-Ray Spectroscopy (SEM-EDX), Optical Emission Spectroscopy (OES), X-Ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), Microvickers, and Strain Recovery test. The results of this study showed that the microstructure of the as-cast and as-homogenized alloy consisted of two phases, ? [D03] and ?, with a rosette-like morphology. DQ and UQ quenching methods resulted in the formation of ? [D03] and ?' phases, meanwhile, the SQ quenching method not only resulted in the mentioned phase but also the ? phase. Furthermore, the hardness values were 288.71 VHN (As-Cast), 300.21 VHN (As-Homogenized), 232.2 VHN (DQ), 240.1 VHN (UQ), and 289 VHN (SQ), respectively. The percentage of strain recovery could not be measured as the samples experienced failure when bent."

"Paduan ingat bentuk merupakan salah satu material cerdas dengan kemampuan kembali ke bentuk semula setelah diberi perlakuan panas. Paduan berbasis Cu merupakan salah satu material yang bisa digunakan sebagai alternaltif dari paduan Ni-Ti yang telah umum digunakan, memiliki sifat ingat bentuk yang baik dan biayanya yang terjangkau. Pada penelitian ini dipelajari pengaruh metode pencelupan terhadap struktur mikro dan kekerasan paduan Cu-25,9Al-3,6Mn (at. %). Sampel dibuat dengan metode pengecoran gravitasi, kemudian dihomogenisasi pada temperatur 900 °C selama 2 jam dan didinginkan pada temperatur ruang. Selanjutnya dilakukan perlakuan panas betatizing pada temperatur 900 °C selama 30 menit dan dilanjutkan dengan tiga metode pencelupan, yaitu Pencelupan Langsung (Direct Quench/DQ), Pencelupan Naik (Step Quench/SQ) dan Pencelupan Bertahap (Step Quench/SQ). Tahapan karakterisasi dilakukan menggunakan Optical Microscope (OM), Scanning Electron Microscope-Energy Dispersive Xray Spectroscopy (SEM-EDS), X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), strain recovery test, dan Microvickers. Hasil penelitian menunjukkan bahwa struktur mikro paduan as-cast dan as- homogenized terdiri atas matriks fasa β dan fasa kedua γ dengan morfologi rosette-like di dalam matriks dan batas butir. Hasil pencelupan DQ dan UQ menghasilkan fasa martensit β′ berupa garis tipis dan fasa β, sedangkan pencelupan SQ memiliki fasa martensit β′ berupa garis tipis, fasa β , dan fasa γ sisa akibat laju pendinginan yang lambat. Untuk nilai kekerasan paduan adalah 293,2 HV (as-cast), 311,3 HV (as-homogenized), 286,7 HV (DQ), 287,1 HV (UQ) dan 283,5 HV (SQ). Strain recovery tidak dapat diukur karena sampel mengalami perpatahan saat ditekuk.

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Shape memory alloy is one of the smart materials that have capability to remember their original shape after deformation followed by heating at certain temperature. Cu-based alloys can be used as an alterlative to the commonly used Ni-Ti alloys, has good shape memory properties and is affordable. In the research, the effect of quenching method on microstructure and hardness of Cu-25.9Al-3.6Mn (at. %) alloy was studied. The alloy was prepared by gravity casting and homogenized at 900 °C for 2 hours followed by cooling at room temperature. Furthermore, betatizing was carried out at 900 °C for 30 minutes and followed by three quenching methods, Direct Quench (DQ), Up Quench (UQ) and Step Quench (SQ). The Characterization was conducted by Optical Microscope (OM) Scanning Electron Microscopy -Energy Dispersive Xray Spectroscopy (SEM-EDS), X-Ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), strain recovery test, and microvickers. The results of observations of the as-cast and as-homogenized microstructure alloys consist of a β phase matrix and a γ phase precipitate with rosette-like morphology in the matrix and grain boundaries. DQ and UQ quenching results have β′ martensite phase in the form of thin lines and retained β phase, while SQ quenching has β′ martensite phase in the form of thin lines, retain β phase, and retain γ phase appears due to slow cooling rate. The alloy hardness values are 293.2 HV (as-cast), 311.3 HV (as-homogenized), 286.7 HV (DQ), 287.1 HV (UQ) and 283.5 HV (SQ) respectively. Strain recovery could not be measured from the samples because the samples fracture when bent."