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Abstrak :
Perkembangan industri elektronik di Indonesia semakin maju pesat dan tentunya membutuhkan tingkat akurasi produksi yang tinggi serta proses yang ramah terhadap lingkungan. Paduan solder SnPb perlu ditinjau karena sudah dilarang pengunaanya mulai 1 juli 2006 di negara maju mengingat sifat toxic Pb yang sangat berbahaya. Sebagai salah satu alternatif untuk mengganti unsur Pb maka dilakukan modifikasi unsur Zn yang dipadukan dengan unsur timah (Sn) dan tembaga(Cu) untuk memperoleh sifat fisik dan mekanik yang mendekati sifat SnPb. Metoda penggabungan secara metalurgi pada proses pembasahan dengan dasar sudut kontak dan pencapaian suhu solidus juga sebagai bentuk karakterisasi yang diperlukan. Pengujian dilakukan terhadap paduan terner Sn-0.7Cu-xZn dengan metoda peleburan Sn dan Cu yang dilanjutkan dengan penambahan variasi unsur Zn 22,24;19,37;16,47,15,14;14,29 dan 9,08 % dan dilakukan pengujian temperatur leleh (DSC test) serta pengujian pemanasan diatas tembaga,, mampu basah (wettability), tegangan geser (shear stress),kerapatan massa(density), kekerasan mikro dan makro(Micro and Macro hardness), dan pengamatan struktur mikro. Hasil pengujian menunjukkan bahwa penambahan kandungan Zn pada paduan terner berbasis Sn-0.7Cu-xZn akan menurunkan temperatur leleh secara signifikan. Kekuatan geser paduan terner terbesar diperoleh pada penambahan 9,08% Zn serta terkecil diperoleh pada penambahan 22,24 % Zn. Tingkat kekerasan paduan terner Sn0.7CuxZn terbesar diperoleh pada prosentase 22,24 % Zn dan terkecil diperoleh pada prosentase 9,08% Zn. Adapun dari pengamatan struktur mikro terlihat bahwa sebaran fasa intermetalik Cu3Sn dan fasa eutektik Sn cukup signifikan terjadi pada paduan Sn0.7CuxZn;

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Electronic industrial has developed rapidly as customer consumption. So that for an accuracy level and environmentally friendly is needed as base on production process. SnPb soldering is banned in developed country since july 2006, then the aim is to explore the material which have to eliminate Pb by using other free lead element to void toxic of lead solder as human health and environment protection. One of the potential element was studied is Zinc alloyed Tin and Copper on variety composition of Zinc. The method was carried out by using XRD measurement, microstructure observation and melting point tested to analyses hardness, shear strength and wettability behavior. Experimentally as shown that increasing of Zn (22,24;19,37;16,47;15,14;14,29 and 9,08) has effect to physically and mechanical properties. Shear stress on terner alloys has higher value in 22,24%Zn, and lower value in 14,29%Zn. Hardness level on terner alloys has higher value in 14,29%Zn and lower value in 12%Zn. Melting point has decreasing in increasing of Zinc content. Metallography observation has identified that intermetalic Cu3Sn and eutectic Sn are scattered in Sn0.7CuxZn alloy.

Abstrak :
This book provides the most up-to-date knowledge and data available on the reliability of lead-free solder interconnects. The content has been written by leading experts working in this important technology area. Both fundamental research and practical considerations are addressed. Environmental regulations are driving the worldwide adoption of lead-free soldering technology for electronics packaging, board assembly, and related manufacturing operations. While a significant amount of research and development work has been conducted in recent years on manufacturing issues to enable the conversion to lead-free solders, data from studies related to the reliability of lead-free solder interconnects are still emerging. Many research projects around the world have been undertaken to study lead-free solder reliability under different loading conditions. The results of these studies have been reported rather sporadically at various technical conferences.

Abstrak :
Meningkatnya kebutuhan akselerasi untuk penemuan material untuk perovskite 3D sangat penting untuk menemukan material yang bebas timah dan ramah lingkungan untuk semikonduktor dan sel surya. Solusi dominan untuk tren ini bergantung pada klasifikasi material dan penyaringan sejumlah besar material perovskit yang dilakukan setelah simulasi ab-initio. Untuk menyelesaikan masalah dua langkah, kami menggunakan algoritme pembelajaran mendalam sebagai cara untuk mengeluarkan materi baru, mempercepat penemuan materi, dan memberikan opsi yang lebih cepat untuk bereksperimen. Dalam studi ini, pembuatan perovskit 3D bebas timah baru melibatkan dua algoritme: berbasis generasi dan berbasis prediksi. Model yang digunakan masing-masing didasarkan pada Conditional Variational Autoencoders (CVAE) dan Convolutional Neural Networks (CNN). Metrik evaluasi kerugian divergensi khusus Kullback-Leibler sebesar 38 dihasilkan dari dekoder CVAE. Skor R2 0,74 - 0,81, Akurasi 0,73 - 0,87, MAE 0,3631 - 6,2339, RMSE 0,34 - 0,57 diperoleh dari 4 model prediksi yang berbeda berdasarkan 4 properti menggunakan tipe regresi dan multi kelas. Eksperimen dengan Materials Studio juga dilakukan untuk memvalidasi hasil yang dihasilkan dari algoritma CVAE. Eksperimen ini menggunakan CsPbBr3 sebagai properti target untuk membuat material baru, PrLiO3. Seperti yang diperkirakan, energi celah pita PrLiO3 kelas 2 (0 < x ≤ 1 eV) dihitung dari Materials Studio menjadi 0,979 eV, menunjukkan bahan semikonduktor dan kemampuan prediksi yang tepat dari algoritme. ......The growing need of acceleration for materials discovery for 3D perovskites are imperative to find lead-free and environmentally friendly materials for semiconductors and solar cells alike. The dominant solutions for these trends rely on the classification of materials and filtering of a huge range of perovskite materials done after ab-initio simulations. To resolve the two-step problem, we used a deep learning algorithm as a way to output new materials, accelerate materials discovery and providing quicker options to experiment upon. In this study, the generation of new lead-free 3D perovskites involves two algorithms: generational-based and prediction-based. Models used were based on Conditional Variational Autoencoders (CVAE) and Convolutional Neural Networks (CNN) respectively. The evaluation metrics Kullback-Leibler custom divergence loss of 38 were generated from the CVAE decoders. R2 score of 0.74 - 0.81, Accuracy of 0.73 - 0.87, MAE of 0.3631 - 6.2339, RMSE of 0.34 - 0.57 are obtained from 4 different prediction models based on the 4 properties using both regression and multi-class type. Experiments with Materials Studio was also done to validate the generated result of the CVAE algorithm. This experiment used CsPbBr₃ as the target properties to create the new material, PrLiO₃. As predicted, the band gap energy of PrLiO₃ class 2 (0 < x ≤ 1 eV) was calculated from Materials Studio to be 0.979 eV, indicating a semiconductor material and the correct predictive capability of the algorithm.

Abstrak :
In modern medicine, a radiation scans is an very important examination tool for making a diagnosis and subsequent treatment plan. Among the range of medical examinations, Computed tomography (CT) is being performed in an increasing number of cases and a CT scan uses the most radiation of any diagnostic exam. On the other hand, radiation protection during scanning is not typical for bodily regions other than those designated for examination. Therefore, the aim of this study was to develop a lead-free fused radiation shielding fiber (RSF) and to evaluate its effectiveness with a view to reducing radiation exposure to only the effective dose or less in a CT scan by means of a multilayer structural coating. A GE High Speed Advantage Spiral CT was used to conduct measurements using a FH-40G (Eberline, USA) proportional digital counter survey meter. In a brain CT scan, abdominal CT scan, and knee CT scan, two-way ANOVA was used to analyze the changes in radiation dosage and to examine the correlation based on body parts and thickness of the RSF. In addition, when significant results were obtained, a Duncan post hoc test was used to examine the difference depending on each condition. In the brain CT scan, the highest exposure to secondary radiation was measured in the chest, which was closest in distance. The use of a 3- mm shielding fiber resulted in a shielding effect of approximately 65% shielding effect compared to the initial exposure dose. In the abdominal CT scan, no exposure dose was detected in the head area, which had been shielded with the 3-mm shielding fiber. In a knee CT scan, 1-mm shielding fiber was sufficient to demonstrate a shielding effect. The RSF developed in this study may help reduce low-dose exposure to secondary X-rays, such as scattered rays.

Abstrak :
Lead-free solders are used extensively as interconnection materials in electronic assemblies and play a critical role in the global semiconductor packaging and electronics manufacturing industry. Electronic products such as smart phones, notebooks and high performance computers rely on lead-free solder joints to connect IC chip components to printed circuit boards. Lead free solder : mechanics and reliability provides in-depth design knowledge on lead-free solder elastic-plastic-creep and strain-rate dependent deformation behavior and its application in failure assessment of solder joint reliability. It includes coverage of advanced mechanics of materials theory and experiments, mechanical properties of solder and solder joint specimens, constitutive models for solder deformation behavior; numerical modeling and simulation of solder joint failure subject to thermal cycling, mechanical bending fatigue, vibration fatigue and board-level drop impact tests.