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"A collective effort of 53 recognized experts on aluminum and aluminum alloys. This book is a joint venture by world-renowned authorities and the Aluminum Association Inc. and ASM International."

"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."

"Effect of Ni content on the hardness, corrosion rate and heat stability of cladding structure material with an alminium base alloy. The development of cladding structure material with an aluminium base alloy was performed by variation of Ni content in the alloy. Various of Ni content in alloy will generates material properties changes in mechanical, physical, and thermal. The investigation and development of cladding structure material was studied order to to get materials which have good mechanical properties and corrosion resistance. The examination of the hardness of -eNi structure materials was observed using vickers method..."

"Aluminium alloys are developed as airplane body due to their lighter weight compared to steel and good formability. Aluminium 7XXX series with Zn and Mg alloying elements is commonly used because its mechanical properties can be improved through a deformation process. A deformation process such as cold rolling may increase the hardness of an alloy through strain hardening. An annealing process following the deformation process will recover ductility through stress relief, recrystallization, and grain growth mechanisms. This research aimed to discover the effect of cold rolling and annealing temperature on the recrystallization and mechanical properties of Al-4.7Zn-1.8Mg (wt. %) alloy. The alloy was produced by a squeeze casting process. Homogenization was conducted at 400oC for 4 hours followed by cold rolling with degrees of deformation of 5%, 10%, and 20%. The samples with 20% deformation were then annealed at 300oC, 400oC, and 500oC for 2 h. The Vickers hardness test was performed on the cold-rolled and annealed samples to reveal the strain hardening effect and subsequent recrystallization process. The microstructure was observed using an optical microscope and a Scanning Electron Microscope (SEM). The results showed that the higher the deformation, the more elongated the grains. Deformation of 5, 10 and 20% led to grain shape ratios of 2.19, 3.19 and 4.59, respectively and increase in the hardness of the alloy from 69.5 VHN to 95.3, 100.1 and 105.4 VHN, respectively. Slip bands and cross slips were found only in the 20% deformed samples. The annealing process resulted in recovery at 300oC, followed by recrystallization at 400oC (dgrain ~290 ?m) and grain growth at 500oC (dgrain ~434 ?m). Annealing temperatures of 300oC, 400oC and 500oC decreased the hardness of the alloy from 105.4 VHN to 71.5, 96.8 and 95.3 VHN, respectively."

"Designed for use by practicing engineers, and maintenance and operating personnel, who are concerned with the problem of corrosion of aluminum in their daily job functions. DLC: Aluminum--Corrosion."

"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."