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"This book focuses on strengthening and joining materials by means of plastic deformation, gathering extended research papers presented at the AIMTDR 2016 conference. Plastic deformation is used in materials processing to improve the strength of the material. For example, the rod/screw used to connect the cooker handle to the main body has to be strong and sustainable; such rods can be strengthened by plastic deformation (using multi-stage forming operations etc.). Similarly, joining by means of plastic deformation is highly valuable since it avoids the material and environmental degradation often caused by fusion welding processes. The book discusses various processing techniques in which plastic deformation is used to strengthen materials – e.g. in equal channel angular extrusion, autofrettage etc., or to join materials without melting them – e.g. in friction stir processing, riveting etc. Offering an extensive guide, the book includes chapters on roll bonding, equal channel angular pressing, autofrettage, friction stir processing/welding, magnetic pulse welding, and riveting – processes used to strengthen and join a variety of materials for lightweight applications and sustainable manufacturing. The contents of this book will be useful to researchers and practitioners alike. "

"Severe plastic deformation (SPD) adalah metode yang digunakan untuk memperoleh baja dengan sifat mekanis yang baik tanpa penambahan microalloyed. Perubahan struktur mikro setelah SPD akan meningkatkan sifat mekanis material dengan penghalusan ukuran butir. Pada penelitian ini digunakan baja karbon AISI 1010 yang di proses menggunakan metode Thermo-Mechanical Control Process (TMCP) dengan pemanasan awal hingga 1100 °C dan pengerolan pada temperatur 650 °C dengan variasi deformasi double pass rolling dan pendinginan udara. Pengamatan struktur mikro menggunakan teknik metalografi dengan etsa nital 2% dan 5%. Pengukuran ukuran butir dengan metode Jeffries sesuai ASTM E-112-96 dan uji kekerasan dengan metode Vickers. Uji korosi menggunakan metode polarisasi dalam larutan NaCl 3,5% sesuai ASTM G5 dan hydrogen charging test. Tujuan dari penelitian ini adalah untuk mempelajari struktur mikro dan kekerasan baja karbon rendah setelah proses severe warm plastic deformation dan ketahanan korosinya terhadap NaCl dan Hydrogen Induced Cracking.

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Severe plastic deformation (SPD) is one method used to get steel with excellence mechanical properties without micro alloyed addition. The structural changes caused by SPD are reflected in improved mechanical properties of metals especially hardness and yield stress by converting coarse grain to ultrafine grained. In this research used low carbon steel AISI 1010 treated with Thermo-Mechanical control process (TMCP) consist of reheating until 1100°C and double pass reverse rolling on 650°C with variation of deformation and air cooling. Metallographic technique implemented in order to observe the final microstructure and 2% and 5% nital etch used to observe final ferrite size and morphologies. Grain size measured using Jeffries methods according to ASTM E 112. Hardness test used Vickers method. Corrosion test worked out using polarisation with NaCl 3,5% as per ASTM G5 and Hydrogen charging test. The main objective of this research is to studying morphology of microstructure and hardness of low carbon steel after severe warm plastic deformation and the corrosion resistance to NaCl and Hydrogen Induced Cracking."

"Metode cold spray adalah proses disposisi kecepatan tinggi dimana partikel kecil (1 - 50 _m) dalam keadaan padat dipadu dengan gas yang dipanaskan dan dipercepat hingga kecepatan supersonik. Adhesi partikel hanya disebabkan oleh energi kinetik pada saat tumbukan. Proses ini menggunakan kecepatan tinggi ketimbang temperatur tinggi untuk menghasilkan coating, dan karenanya mengurangi reaksi-reaksi yang tidak menguntungkan dari proses thermal spray. Serbuk aluminium dengan kemurnian 99.9 % disemprotkan dengan metode cold spray pada tiga jenis substrat yang berbeda; paduan magnesium ZE41A-T5, paduan AA7075 dan baja 4130. Kemudahan untuk permulaan deposisi partikel coating sangat bergantung pada karakteristik substrat. Oleh karena itu pada penelitian ini dilakukan karakterisasi cold spray coating pada ketiga substrat untuk mempelajari pengaruh karakteristik substrat pada kualitas ikatan antara substrat dan coating. Karakterisasi dilakukan dengan pengamatan struktur mikro, dan kekerasan mikro yang difokuskan pada daerah antar muka. Hasil penelitian ini menunjukkan bahwa: (i) terbentuk lapisan Al2O3 pada daerah antar muka ketiga sampel; (ii) coating pada substrat paduan Mg memiliki kekerasan tertinggi dan persentase porositas terendah, yang dapat menunjukkan ikatan antar substrat dan coating yang berkualitas baik; (iii) mekanisme ikatan yang mungkin terjadi adalah penguncian secara mekanis (mechanical interlocking).

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Abstract: Cold spray is a recent development by which a high-rate deposition process of small particles in solid state are mixed with heated gas and accelerated to supersonic velocities through a nozzle. The particles impact the target surface with sufficient kinetic energy to cause plastic deformation and consolidation with the substrate material to bond together, rapidly building up a layer of deposited material. This process uses high velocity rather than high temperature to produce coatings, and thereby minimize many disadvantages of high temperature reactions, which are characteristics of typical thermal sprayed coatings. Aluminium powder of 99.9 wt. % purity has been sprayed by using cold spray method onto a range of substrates; which are ZE41A-T5 magnesium alloy, AA7075 aluminium alloy and 4130 steel. The ease of initiation of deposition depends critically upon substrate type. Hence, this research was carried out to characterize the substrate materials and investigate the possible bonding mechanism at the interface. It was concluded that the possible mechanism of bonding is mechanical interlocking, which is supported by the evidence that the interface at the entire samples is not a straight line that may due to generation of interface curvature. It was also observed that 1 ' 2 _m thickness of Al2O3 layer has formed at the interface of all samples, which due to the reaction of aluminum particles with oxygen."

"Seiring dengan meningkatnya investasi di sektor infratruktur, gedung-gedung pencakar langit, dan proyek otomotif berbanding lurus dengan permintaan pasar global akan baja perkakasdengan nilai USD 5.7 miliar di tahun 2023. Salah satu tipe baja perkakas yang umum digunakan di dunia industri sebagai pisau pemotong adalah baja AISI D2.Material ini dapat ditingkatkan kekuatan dan kekerasannya melalui proses perlakuan panas. Perlakuan panas dilakukan untuk mentransformasi fasa austenit menjadi martensit. Fasa austenit yang merupakan fasa induk memiliki peran penting dalam menghasilkan fasa akhir dengan sifat mekanis yang optimal oleh karena itu penelitian terkait fenomena penghalusan austenit atau yang dikenal dengan sebutan prior austenite grain (PAG) terus dikembangkan. Salah satu metode penghalusan butir austenit dilakukan dengan kombinasi dari proses deformasi plastis (canai dingin) sebelum dilakukan perlakuan panas.Dengan diterapkannya deformasi plastis, maka akan menghasilkan lebih banyak cacat kristal sebagai area nukleasi atau pengintian fasa austenit pada saat proses pemanasan serta lebih banyak energi yang tersimpan sebagai pendorong (driving force) proses pengintian. Penelitian ini berfokus pada analisa ukuran prior austenit grain (PAG) yang berdampak terhadap sifat mekanis dari baja perkakas AISI D2, terutama kekerasan dan ketahanan aus hasil dari proses deformasi sebelum perlakuan panas serta efek dari waktu tahan pada temperatur austenitisasi. Spesimen baja AISI D2 dengan kombinasi deformasi paling tinggi (24.6%) dengan waktu tahan pada temperatur austenitisasi 600s ternyata memiliki ukuran rata-rata PAG paling halus yakni 4.182 µm. Ukuran PAG yang halus berpengaruh terhadap nilai kekerasan dan ketahanan aus (nilai kehilangan volume) material yang paling tinggi yaitu 63.26 HRC dan 0.120mm3 yang turut dikonfirmasi melalui pengujian kekerasanRockwell C dan ketahanan aus metode abrasif. Dari penelitian ini dapat disimpulkan bahwa dengan meningkatnya persentasi deformasi maka terdapat kecenderungan untuk menghasilkan ukuran PAG yang semakin halus yang berdampak pada meningkatnya kekerasan dan ketahanan aus material.

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Along with the increasing of investment in infrastructure, skycrapers, and automotive project, significantly increasing global market demand for tool steel with total value of USD 5.7 billion in 2023. One of the popular type of tool steel which have been used as cutting tool is AISI D2. This material is heat treatable to improve its strength and hardness. Heat treatment is conducted to transform austenite phase become martensite.Austenit as parent phase has primary role in resulting final phase with optimum mechanical properties, in which research that related with autenite or known as prior austenite grain (PAG) continuously developed. PAG refinement method in this research is a combination of plastic deformation (cold rolling) before heat treatment, which the greater deformation percentage, the more crystal defect formed as austenite nucleation area during heating also store the energy as nucleation driving force. The focus of this research will be the analysis of prior austenite grain (PAG) which affecting it mechanical properties, especially for hardness and wear resistance resulting for plastic deformation before heat treatment and the effect of austenitizatin soaking time.Specimen with combination of deformation percentage of 24.6% with austenitization soaking time 600s has the finest PAG with 4.182 µm. PAG size has effect on material’s highest hardness and wear resistance (volume loss) which is 63.26 HRC and  0.120mm3 which confirmed by Rockwell C hardness testing and abrasive wear resistance testing. From this research, it can be concluded that the higher deformation percentage has tendency in resulting to produce finer PAG size which affecting in improving material’s hardness and wear resistance."

"This handbook covers all areas of nonlocal continuum mechanics including theoretical aspects,computational procedures, and experimental advances. The multidisciplinary scope of articles that comprise this reference are written by internationally recognized experts in the field and stand as the most-up-to-date, established knowledge base on using nonlocal continuum mechanics to characterize material behavior for advanced composites and nano-materials, as well as for engineering scale structures. The handbook is at once a comprehensive reference for academic researchers and engineers in industry concerned with nonlocal continuum mechanics for materials and structures as well as a supplement for graduate courses on a range of topics."

"This handbook covers all areas of nonlocal continuum mechanics including theoretical aspects,computational procedures, and experimental advances. The multidisciplinary scope of articles that comprise this reference are written by internationally recognized experts in the field and stand as the most-up-to-date, established knowledge base on using nonlocal continuum mechanics to characterize material behavior for advanced composites and nano-materials, as well as for engineering scale structures. The handbook is at once a comprehensive reference for academic researchers and engineers in industry concerned with nonlocal continuum mechanics for materials and structures as well as a supplement for graduate courses on a range of topics."