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"This work in three parts presents a summary of the sintered manganese steel properties from 1948 to 2011 involving processing conditions and other characteristics. In the first and third part are given results attained by the authors based on their finding that manganese (cheapest element) during sintering evaporates and by this the vapour cleans the sintering atmospheres from humidity. The second part presents other positive properties of manganese steels in spite of the doubt of oxidation of manganese during sintering and by this excluding the sintering manganese steels what hinderd the use of manganese in production of sintered parts. All results confirm that only manganese vapour according to finding of the authors ensures effective sintering of manganese steels and parts independently on the authors mind. It follows finally from the work that manganese is possible to use for alloying of powder steels sintered also in practice in H/N atmospheres with low purity and also in pure nitrogen."

"This practical reference provides thorough and systematic coverage on both basic metallurgy and the practical engineering aspects of metallic material selection and application. Coverage includes: Practical information on the engineering properties and applications of steels, cast irons, nonferrous alloys, and metal matrix composites."

"Powder metallurgy (PM) is a popular metal forming technology used to produce dense and precision components. Different powder and component forming routes can be used to create an end product with specific properties for a particular application or industry. Advances in powder metallurgy explores a range of materials and techniques used for powder metallurgy and the use of this technology across a variety of application areas.Part one discusses the forming and shaping of metal powders and includes chapters on atomisation techniques, electrolysis and plasma synthesis of metallic nanopowders. Part two goes on to highlight specific materials and their properties including advanced powdered steel alloys, porous metals and titanium alloys. Part three reviews the manufacture and densification of PM components and explores joining techniques, process optimisation in powder component manufacturing and non-destructive evaluation of PM parts. Finally, part four focusses on the applications of PM in the automotive industry and the use of PM in the production of cutting tools and biomaterials."

"Tesis ini membahas hasil penelitian tentang pengaruh arus dan gas pelindung baik pada torch, backing gas dan trailing gas pada pengelasan paduan titanium (Ti-6Al-4V) dengan proses gas tungsten arc welding. Tujuan dari penelitian ini untuk mendapatkan hasil lasan yang optimum dengan variasi arus mulai dari 70, 80, 90, 100, 110 dan 120 amper, voltase 13 volt, kecepatan pengelasan 4,5 in/menit dan aliran gas pelindung pada backing gas 5 l/menit, trailing gas 15 l/menit dan torch gas 15 l/menit.Dari hasil pengujian visual, komposisi kimia, x-ray, sifat mekanik, metalografi dan kandungan hidrogen pada hasil lasan maka didapatkan bahwa pada arus 90 amper kandungan hidrogen pada daerah logam las 60,96 ppm dan pada daerah terpengaruh panas 76,72 ppm ini lebih rendah dibandingkan dengan arus 80 Amper (pada logam las 65,74 ppm dan pada daerah pengaruh panas 95,03 ppm), tetapi kekuatan tarik dengan arus 90 Amper (92,7 kgf/mm²) lebih rendah dibandingkan dengan arus 80 Amper (103,3 kgf/mm²). Kawat las atau logam pengisi sudah sesuai dengan logam induk hal ini ditunjukkan dengan harga kekerasan yang sama pada logam las dan logam induk yaitu 371 Hv. Backing gas dan trailing gas dapat berfungsi dengan baik melindungi daerah lasan hal ini ditunjukkan oleh rendahnya kandungan hidrogen pada logam las dan daerah terpengaruh panas dibandingkan dengan logam induk (80,18 ppm), sehingga terbentuknya presifitat hidrid dan hidrogen embrittlement pada logam las dapat dihindari.

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The research is focused on the effects of current and shielding gas on torch, backing gas and trailing gas of Titanium Alloy (Ti-6Al-4V) using gas tungsten arc welding (GTAW) process. Weld current varies from 70, 80, 90, 100, 110 and 120 Amperes, and need parameters are kept constant such as voltage of 13 Volt, welding speed 4.5 in/minute and flow rate of shielding backing gas was 5 liters/minute, trailing gas and torch gas were 15 liters/minute. Respectively visual, X-ray radiograph, mechanical properties testing and metallographic, chemical composition as well as hydrogen content analysis were performed.

The results show that at the condition of 90 amperes the hydrogen content was 60.96 ppm on the weld and 76.72 ppm on the heat affected zone with tensile strength was 92.7 kgf/mm². This tensile -strength value is lower than that results from 80 Amperes (103,3 kgf/mm²) although the hydrogen content is a bit higher that is 65.74 ppm on weld and 95.03 ppm on heat affected zone. All those hydrogen contents are below the critical value (>100 ppm for formation hydride precipitate and > 240 ppm occur hydrogen embrittlement) which may show that both welding conditions are appropriate welding parameters to avoid hydrogen embrittlement. The filler metal used in this investigation is suitable for Ti-6A1-4V which have identical hardness value weldment of 371 HV."

"Aluminum adalah salah satu logam dengan pengunaan paling banyak di berbagai bidang. Tidak terkecuali, salah satu serinya, yakni seri 6061. Agar dapat digunakan, AA 6061 perlu mengalami beberapa tahapan manufaktur dasar, seperti pengelasan. Walaupun paduan ini memiliki kemampulasan yang baik, tidak menutup kemungkinan bahwa akan terbentuk cacat las setelah dilakukan pengelasan. Penelitian ini bertujuan untuk mengetahui parameter masukan panas yang paling sesuai untuk meminimalisir terjadinya cacat las dan menghasilkan hasil lasan yang baik. Metode yang digunakan adalah pengelasan autogenous Tungsten Inert Gas, dengan sampel AA 6061 berdimensi 120 x 50 x 6 mm, hasil lasan berbentuk bead on plate, menggunakan gas argon sebagai gas pelindung, & memvariasikan parameter kecepatan dan arus pengelasan. Setelah pengelasan, dilakukan pengujian visual, radiografi, metalografi, dan Microvickers. Dari penelitian ini, didapatkan hasil bahwa masukan panas yang terlalu rendah tidak menghasilkan penetrasi pengelasan yang baik dan masukan panas yang terlalu tinggi membuat manik bertekstur kasar dan melebar. Ditinjau dari rasio w/d untuk mencegah terjadinya retak pembekuan (rasio 1 sampai 2), sampel dengan masukan panas 0,45 kJ/mm terkategori sebagai parameter optimal (220 A; 3,8 mm/s). Penggunaan masukan panas yang semakin tinggi menyebabkan penurunan kekerasan di HAZ karena membuat daerah sekitar pengelasan yang terpengaruh panas menjadi lebih luas, sehingga butir tumbuh lebih besar. Oleh karena itu, pengelasan sebaiknya dilakukan dengan masukan panas yang tidak terlalu rendah dan juga tidak terlalu tinggi. Masukan panas yang terlalu rendah menyebabkan penetrasi dangkal dan masukan panas yang teralu tinggi menyebabkan penurunan kekerasan di HAZ yang signifikan.

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Aluminium, being widely utilized in various industries, encompasses numerous alloys, including the widely employed AA 6061. To enable its usage, AA 6061 undergoes essential manufacturing processes, such as welding. Despite its commend able workability, the occurrence of weld defects post-welding remains a possibility. Thus, this research aims to determine the optimal heat input parameters to minimize weld defects and ensure favorable welding outcomes. Autogenous Tungsten Inert Gas (TIG) welding technique was employed, utilizing AA 6061 samples with dimensions of 120 x 50 x 6 mm, resulting in bead-on-plate welds. Argon gas was implemented as the shielding gas, while the welding speed and current parameters were systematically varied. Subsequently, visual, radiographic, metallographic, and Microvickers testing were conducted to evaluate the welds comprehensively. The findings revealed that excessively low heat input resulted in inadequate weld penetration, whereas excessively high heat input caused the formation of coarse and expanded bead textures. Optimal weld performance was achieved by maintaining a width-to-depth ratio of 1:2, crucial for preventing hot cracking, with a heat input parameter of 0.45 kJ/mm (220 A; 3.8 mm/s). Notably, higher heat input levels were observed to induce a reduction in hardness within the Heat Affected Zone (HAZ) due to the enlargement of the heat-affected area, promoting enhanced grain growth. Consequently, welding operations necessitate the careful selection of heat input parameters to ensure both satisfactory penetration and desirable hardness within the HAZ, avoiding extremes of too low or too high heat input. Inadequate heat input leads to superficial penetration, while excessive heat input results in a substantial decline in hardness within the HAZ."

"ABSTRAKResistance Spot Welding (RSW) merupakan proses menyambung logam dengan menggunakan arus dan sifat physical properties logam. Sehingga diperlukan gabungan analisis Electrical-Themal-Mechanical untuk mempelajari hasil las yang memiliki qualitas yang baik. Untuk memprediksi besar nugget las, simulasi RSW model 2D axissymetric dikembangkan dengan menggunakan sifat dari Electrical Contact Resistace (ECR). Tujuan penelitian ini adalah mempelajari pengaruh initial value ECR dan ketebalan ECR terhadap formasi nugget las. Variasi parameter pada penelitian ini adalah arus, ketebalan permukaan kontak, dan initial value ECR. Pada penelitian ini menunjukan bahwa untuk mendapatkan hasil nugget las yang berbentuk elips dan dapat menyambung antar plat metal yaitu dengan menentukan initial value ECR dan ketebalan ECR pada permukaan kontak antar plat metal (Al-Al) lebih besar dibandingkan dengan permukaan plat metal dan elektroda (Al-Cu). Setelah melakukan perbandingan dengan hasil experimen, simulasi RSW dengan menggunakan arus 8 kA dan initial value ECR dari permukaan kontak antar plat metal (Al-Al) dan plat - elektroda (Al-Cu) yaitu 230-28.75 µΩ memiliki selisih rata-rata 4.8 %. Dengan gaya elektroda 500 N dan expansi thermal yang terjadi pada specimen, stress maksimal yang dihasilkan sebesar 4 GPa.

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ABSTRACTResistance Spot Welding (RSW) is a process of joining metals using current and the physical properties of metals. A coupled of Electrical-Thermal-Mechanical analysis is needed to study welding results that have good quality. To predict the size of the welding nugget, the RSW simulation of the 2D axisymmetric model was developed using the properties of the Electrical Contact Resistance (ECR). The purpose of this study was to investigate the effect of the initial value ECR and ECR thickness on the formation of weld nuggets. The parameter variations in this study were current, contact surface thickness, and initial value of ECR. The results of this study showed that in order to achieve weld nuggets that could join metal sheets with ellipse formation weld nugget, the simulation used initial value ECR and ECR thickness of between metal sheets (Al-Al) greater than the contact surface of metal sheet and electrode (Al-Al). By making comparisons with experimental results, welding simulations by using 8 kA current and the initial ECR value of the contact surface between metal sheets (Al-Al) and the metal sheet-electrode (Al-Cu) with 230-28.75 µΩ, had an average error of 4.8%. By using electrode force 500 N and occurring thermal expansion, the maximum generated stress was 4 GPa."

"Magnesium and magnesium alloys offer a wealth of valuable properties, making them of great interest for use across a wide range of fields. This has led to extensive research focused on understanding the properties of magnesium and how these can be controlled during processing. Fundamentals of magnesium alloy metallurgy presents an authoritative overview of all aspects of magnesium alloy metallurgy, including physical metallurgy, deformation, corrosion and applications.Beginning with an introduction to the primary production of magnesium, the book goes on to discuss physical metallurgy of magnesium and thermodynamic properties of magnesium alloys. Further chapters focus on understanding precipitation processes of magnesium alloys, alloying behaviour of magnesium, and alloy design. The formation, corrosion and surface finishing of magnesium and its alloys are reviewed, before Fundamentals of magnesium alloy metallurgy concludes by exploring applications across a range of fields. Aerospace, automotive and other structural applications of magnesium are considered, followed by magnesium-based metal matrix composites and the use of magnesium in medical applications.With its distinguished editors and international team of expert contributors, Fundamentals of magnesium alloy metallurgy is a comprehensive tool for all those involved in the production and application of magnesium and its alloys, including manufacturers, welders, heat-treatment and coating companies, engineers, metallurgists, researchers, designers and scientists working with these important materials."

"Pembangunan infrastruktur yang saat ini sedang berlangsung, banyak menggunakan material baja berkekuatan tinggi sebagai material utama dalam membangun infrastruktur-infrastruktur tersebut. Seperti contoh penggunaan baja SM570 untuk struktur jalan tol layang, dimana proses penyambungan antar struktur baja tersebut digunakan proses pengelasan. Penelitian ini bertujuan untuk mengetahui bagaimana pengaruh kandungan nikel dalam kawat las terhadap struktur mikro dan sifat mekanik hasil pengelasan flux-cored arc welding baja SM570. Penelitian ini menggunakan baja SM570-TMC sebagai bahan uji dengan dimensi 370mm (p) x 300mm (l) x 16mm (t). Pengelasan dilakukan menggunakan metode FCAW dengan gas pelindung CO2 (100%), dengan desain sambungan butt joint (V groove), posisi las 1G, dan variabel kandungan nikel kawat las 0,4%, 1%, dan 1,5%. Pengamatan metalografi dilakukan untuk melihat struktur mikro yang terbentuk pada kampuh las, HAZ, dan logam induk. Radiografi untuk melihat ada tidaknya cacat setelah pengelasan. Sedangkan untuk mengetahui sifat mekanis hasil lasan dilakukan pengujian kekerasan untuk melihat distribusi kekerasan pada kampuh las, HAZ, dan logam induk, uji tarik, uji ketangguhan impak Charpy pada variabel suhu 25°C, 0°C dan -20°C dan uji komposisi menggunakan OES, SEM/EDX. Hasil pengujian menunjukkan bahwa kekerasan tertinggi terdapat pada kandungan nikel 1% dengan nilai kekerasan 228 HV, diikuti oleh 1,5% (217 HV) dan 0,4% (193 HV). Kekuatan tarik tertinggi juga terdapat pada kandungan nikel 1% dengan 585 MPa, diikuti oleh 0,4% (578,5 MPa) dan 1,5% (575,5 MPa). Ketangguhan impak tertinggi juga terdapat pada kandungan nikel 1% (25°C = 186 J, 0°C = 171,5 J dan -20°C = 155 J), diikuti oleh 0,4% (178 J; 162,5 J; 127 J) dan 1,5% (108,5 J; 106,3 J; 77,9 J).

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The highway and underway infrastructure development use high strength steel (HSS) as the main material in building these infrastructure. As an example SM570 steel for the structure of elevated toll roads, where the joining process between steel structures is used the welding process. Therefore, this study was conducted to determine how the effects of nickel content on welding wire to microstructure and mechanical properties in flux-cored arc welding SM570-TMC steel.

This study uses SM570 steel as a test material with dimensions of 370mm (p) x 300mm (l) x 16mm (t). Welding is carried out using the FCAW method with CO2 shielding gas (100%), with a butt joint (V groove) connection design, 1G (flat) welding position, and nickel welding wire variable 0,4%, 1% and 1,5%. Metallographic observations were carried out to see the microstructure formed in the weld metal, HAZ, and base metal. Whereas to determine the mechanical properties of welds, a micro hardness test was used to see the hardness distribution on weld metal, HAZ, and base metal. Radiography to see defects after welding process. The others are tensile test, impact toughness test at temperature variable 25°C, 0°C, and -20°C and composition test (using OES, SEM/EDX).

The test results show that the highest value of hardness occurs in the welding wire containing 1% (228 HV), followed by 1,5% (217 HV) and 0,4% (193 HV). Highest value of tensile strength also occurs in the welding wire containing 1% (585 MPa), followed by 0,4% (578,5 MPa) and 1,5% (575,5 MPa). Highest value of impact toughness also occurs in the welding wire containing 1% (25°C = 186 J, 0°C = 171,5 J and -20°C = 155 J), followed by 0,4% (178 J; 162,5 J; 127 J) and 1,5% (108,5 J; 106,3 J; 77,9 J)."