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"ABSTRAKProses penyolderan pada perakitan modul elektronika berteknologi surface-mount (SMT), dilakukan dengan sistem reflow dan wave. Penyolderan dengan sistem reflow infra-red bersifat unik, karena untuk setiap tipe modal yang diproses perlu dibuat suatu profil temperatur penyolderan sendiri. Pada penelitian ini dilakukan eksperimen penyetelan profil temperatur penyolderan untuk beberapa tipe modul yang berbeda. Untuk proses penyolderan modal dengan komponen di kedua sisi Papan Rangkaian Tercetak, juga telah dilakukan eksperimen dengan tujuan merninimisasi waktu proses dan mengoptimalkan penggunaan peralatan reflow infra-red.Hasil eksperimen pertama menunjukkan bahwa faktor disain geometri dari modul elektronika bersifat sangat dominan dalam penyetelan suatu profil temperatur penyolderan, sehingga modul yang mempunyai kemiripan disain geometri, proses penyolderannya dapat dilakukan dengan menggunakan profil temperatur yang sama. Hasil eksperimen kedua menunjukkan bahwa dengan pengaturan kecepatan konveyor dan enerji radiasi infra-red pada tahap reflow secara tepat, dapat dilakukan penyolderan komponen di kedua sisi modul hanya dengan menggunakan sistem reflow infra-red saja (tanpa sistem wave), bahkan proses penyolderan dapat dilakukan hanya dengan satu langkah. Dengan eksperimen tersebut, dapat dihasilkan minimisasi Manufacturing Lead Time - MLT per modulnya rata-rata sampai 15%.

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Soldering process in electronic module assembling by Surface Mount Technology can be done with reflow and wave system. Soldering by infra-red reflow system is unique, because each module type needs a soldering temperature profile for its soldering process. Experiment to set-up soldering temperature profile for processing several different modules type and experiment for soldering process module with components in both side of Printed Circuit Board to minimize time process and to optimalization the use of infra-red equipment, have been done.

From the first experiment is indicated that geometry design of electronic module is very dominant to setting up soldering temperature profile, so the soldering process for modules which have similar geometry design can be done with the same temperature profile. From the second experiment is indicated that by right controlling of conveyor velocity and infra-red radiation energy during reflow step, the soldering process for components in both side of module can be done with only the infra-red reflow system (without wave system). Even this process can be done just on a single step soldering process. With that experiment, Manufacturing Lead Time (MLT) per module can be minimize up to 15 %."

"Die soldering terjadi ketika lelehan alumunium menempel ke permukaan material cetakan dan tetap tertinggal setelah pengeluaran produk cor, yang berakibat pada peningkatan biaya produksi dan kehilangan produksi pada industri pengecoran. Perlakuan permukaan seperti nitridisasi dianggap sebagai cara yang efektif dalam menahan terjadinya reaksi soldering. Pada penelitian ini, baja perkakas H13 dengan tiga perlakuan permukaan berbeda dicelup ke dalam lelehan alumunium ADC12 pada temperatur 680°C dan di tahan selama 30 detik, 30 menit, 2 jam, dan 5 jam.Karakterisasi permukaan baja difokuskan pada struktur mikro, distribusi kekerasan, komposisi kimia, kekasaran permukaan, dan kehilangan berat dari baja perkakas H13. Hasilnya ditemukan bahwa shot peening sebelum nitridisasi menghasilkan kekerasan permukaan dan kedalaman lapisan nitrida yang lebih tinggi, yaitu 1033 HV (68 HRC) dan 105 µm, dibanding dengan perlakuan nitridisasi saja, 1033 HV (68 HRC) dan 105 µm.Hasil pernelitian ini juga menunjukkan bahwa perlakuan permukaan yang berbeda memberikan morfologi permukaan yang berbeda, dimana perlakuan shot peening saja menghasilkan kecenderungan soldering yang disertai pembentukan lapisan intermetalik; namun soldering tidak ditemukan pada permukaan dengan perlakuan nitridisasi dan shot peening yang dilanjut dengan nitridisasi.

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Die soldering occurs when molten aluminum sticks to the surface of a die material and remains there after the ejection of the part. This resulted in low productivity and economic value in the foundry industry. Nitriding surface treatment is considered as an effective way to prevent soldering. In this research, H13 tool steel with three different surface treatments were dipped into the molten of ADC12 at temperature 680°C and held for 30 seconds, 30 minutes, 2 hours, and 5 hours.

Characterizations on the surface of the steel were focused on the microstructure, microhardness profile, chemical composition, surface roughness, and weight loss of the H13 tool steel. It was found that shot peening prior to nitriding gives a higher surface hardness and depth of nitride layer of H13 tool steel, 114 HV (>70 HRC) and 120.5 µm, than the nitriding only process, 1033 HV (68 HRC) and 105 µm.

The research results also showed that different surface treatment produced different morphologies of the steel surface in which the shot peening only treatment showed a soldering tendency with the present of intermetallic layer; while the soldering was not found on the nitrided and shot peened - nitrided sample."

"If you work with soldering processes or soldered components, Principles of Soldering will help you understand and solve practical engineering challenges. Clearly written and well referenced, this book takes you from the fundamental characteristics of solders, fluxes, and joining environments to the impact these have in the selection and successful use of soldering processes. Priority is given to the fundamental principles that underlie this field of technology rather than recipes for making joints. Striking a balance between being unduly simplistic or overly mathematical in their approach, the authors provide the critical analysis that is missing from much of the literature on soldering. An entire section is devoted to the difficult art of fluxless soldering and includes strategies for devising successful processes. The final chapter is devoted to recent advances in soldering technology and covers a variety of topics including lead-free solders, flip-chip interconnection, diffusion soldering, amalgams as solders, composite solders and other hot areas of research. Containing approximately 200 figures and 60 tables, this book updates and greatly expands the soldering content in the book Principles of Soldering and Brazing (1993) by the same authors. A companion volume, Principles of Brazing, is in development."

"The topics addressed in this proceedings volume include active brazing (an area of increasing R&D interest); conventional brazing an soldering alloys; wetting and fundamental properties studies; modeling and mechanical analysis and/or characterization; and process technology. All of the papers in this volume have been editorially reviewed. Both the hardcopy and CD contain an author s index for easy reference, and the CD volume is fully searchable by keyword."

"Paduan Al-7wt%Si merupakan salah satu jenis paduan aluminium silikon yang memiliki aplikasi besar dalam dunia pengecoran khususnya proses die casting. Dalam aplikasi di dunia industri die casting terdapat problem yang disebut dengan die soldering. Die soldering adalah fenomena menempelnya aluminium cair pada permukaan material cetakan dan ada bagian benda casting yang tersisa ketika dikeluarkan dari cetakan. Reaksi die soldering biasanya terjadi pada pengecoran cetak tekan dengan tekanan tinggi dalam paduan aluminium dan membentuk lapisan intermetalik antara aluminium cair dan cetakan. Fenomena ini menyebabkan rusaknya cetakan serta mengakibatkan kualitas permukaan cetakan yang jelek, sedangkan biaya akan terus meningkat. Penelitian ini dilakukan untuk melihat karakteristik pembentukan ketebalan dan kekerasan dari lapisan intermetlic selama proses pencelupan. Dalam penelitian ini, ditemukan adanya lapisan fasa binary dari lapisan intermetalik FeAl2, Fe2Al5, and FeAl3 yang ditemukan di permukaan baja. Penelitian ini bertujuan untuk mencari morfologi dan karakteristik dari lapisan AlxFeySiz yang meliputi ketebalan dan kekerasan selama proses pencelupan. Material cetakan untuk penelitian ini adalah baja perkakas H13 yang dicelup dengan Al-7wt%Si dengan temperatur holding 700°C, 720°C, dan 740°C serta penambahan mangan dengan 0.1, 0.3, 0.5, dan 0.7 %. Dari hasil penelitian diperoleh bahwa penambahan mangan diatas 0.3% pada temperatur 700°C efektif menurunkan die soldering dari ketebalan lapisan 101 mikron sampai 86 mikron di kadar 0,5%Mn dan 54 mikron pada kadar Mn 0,7%. Fenomena tersebut juga terjadi pada temperatur 740°C. Sedangkan pada temperatur 720°C, penambahan Mn efektif menurunkan fenomena die soldering setelah penambahan 0.5%Mn. Adapun kekerasan lapisan intermetalik sangat bervariasi, hal ini disebabkan karena ukuran kekerasan sangat tergantung terhadap kandungan paduan FexAly yang terdapat dalam lapisan. Semakin banyak kandungan Fe dalam paduan lapisan intermetalik FexAly, maka kekerasannya semakin meningkat, begitu juga sebaliknya. Dengan demikian, penambahan mangan terhadap Al-7wt%Si tidak mempunyai pengaruh yang signifikan terhadap kekerasan lapisan intermetalik.

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Al-7wt%Si is one of aluminium alloys which have largest application in the world of casting, especially in die casting process. In the application of die casting technology, there is a dominant problem names die soldering. Die soldering is a phenomenon in which molten aluminium ?welds? to the die surface and remains there after the ejection of the part. Soldering reactions are commonly observed during high pressure die casting of aluminium alloys, and involve the formation and growth of interfacial intermetallic layers between the die and the cast alloy. This phenomenon resulting in damage to the die and poor surface quality of the casting, but increase the production cost. This research is done to study the thickness and hardness characteristic formation of the intermetallic layers during dipping test.

In this research, the appeared binary phase of intermetallic layer is FeAl2, Fe2Al5, and FeAl3 which available at steel?s surface. This research aim is investigating morphology and characteristic of AlxFeySiz intermetallic layer which consist thickness and hardness of the layer during immersing period. The testing material for this research is annealed tool steel H13 which is immersed at Al-7%Si with various holding temperature at 700°C, 720°C, and 740°C and also added by four types mangan (Mn) composition at each temperature. The compositions of this mangan are 0.1, 0.3, 0.5, and 0.7 %.

From the laboratory activity, it was clearly shown that additional Mn above 0.3% at 700°C can decrease die soldering effect significantly. This phenomenon can be seen from the intermetallic layer thickness formed with additional Mn at 101 to 86 micron for 0.5% Mn content and 54 micron for 0.7% Mn. This tendency is happen for 740°C reacting temperature also. But for 720°C reacting temperature, the effect of additional Mn for decreasing die soldering effect start from 0.5% Mn content.

Then, intermetallic layer formed are vary due to FexAly alloy content at layer itself. The more FexAly alloy content, the more hardness level formed; and vice versa. So that, additional Mn to Al-7wt%Si did not have significant effect to hardness of intermetallic layer formed due to spreading of random hardness level at each intermetallic layer."