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"A reference listing the electrical and magnetic properties of metals. Each data entry includes the material's name, temper, UNS number, property values in SI and alternate units, and a source of the data. DLC: Metals--Electric properties."

"Sampel polikristalin La0.7Ba0.1Sr0.2Mn1-xCuxO3 x = 0; 0.05; 0.10; 0.15 telah disintesis menggunakan metode sol-gel. Pengaruh substitusi tembaga terhadap sifat kemagnetan dan kelistrikan dari sampel La0.7Ba0.1Sr0.2Mn1-xCuxO3 telah diselidiki menggunakan X-Ray Diffractometer XRD, Scanning Electron Microscope SEM, Energy Dispersive X-Ray EDX Vibrating Sample Magnetometer VSM , dan Cryogenic Magnetometer. Parameter struktural yang telah didapatkan menggunakan analisis struktural rietveld refinement menunjukkan bahwa sampel La0.7Ba0.1Sr0.2Mn1-xCuxO3 memiliki struktur rhombohedral dengan space group R-3c tanpa adanya impuritas yang dapat dideteksi. Tidak adanya impuritas dalam sampel yang telah disintesis juga terlihat pada hasil yang didapat dari EDX. Perubahan ukuran grain terjadi ketika tembaga telah tersubstitusi pada sampel. Analisis struktural yang telah dilakukan menunjukkan adanya korelasi antara struktur kristal terhadap sifat kemagnetan dari sampel. Transisi fasa feromagnetik metal menjadi paramagnetic insulator terjadi pada semua nilai konsentrasi doping. Hasil penelitian yang telah dilakukan membuktikan bahwa substitusi tembaga akan melemahkan interaksi feromagnetik double exchange sehingga berakibat menurunnya magnetisasi saturasi dan temperatur transisi sampel.

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Polycrystalline sample of La0.7Ba0.1Sr0.2Mn1 xCuxO3 X 0 0.05 0.10 0.15 was synthesized using sol gel method. The effect of copper substitution on the magnetic and electrical properties has been investigated by means of X Ray diffraction XRD, Scanning Electron Microscope SEM, Energy Dispersive X Ray EDX, Vibrating Sample Magnetometer VSM, and Cryogenic Magnetometer. The structural parameter obtained using structural analysis by rietveld refinement shows that sample La0.7Ba0.1Sr0.2Mn1 xCuxO3 crystallize in rhombohedral structure with R 3c space group without any detectable impurity. This argument is confirmed from EDX measurement result. Different grain size are noticeable for different copper concentration.

The structural analysis suggested that there are a strong correlation between structure and magnetic property. Ferromagnetic metal to paramagnetic insulator transition occurred at all copper concentration. The experimental results shows that ferromagnetic double exchange interaction will grow weaker upon copper substitution on manganese ion. This will cause a reduction in the magnetization saturation and metal to insulator transition temperature."

"Paduan Al-Zn-Mg (Seri 7xxx) telah banyak dikembangkan dalam berbagai aplikasi, terutama dalam industri penerbangan sebab memiliki kekerasan yang tinggi sementara densitasnya rendah. Paduan tersebut umumnya diperkuat melalui perlakuan penuaan, di mana terjadi difusi atom-atom Zn dan Mg dari larutan padat sangat jenuh sehingga terbentuk presipitat metastabil. Selain itu, paduan dapat diperkuat pula dengan penambahan Ti yang akan memperhalus butir. Tujuan dari penelitian ini adalah untuk mengetahui pengaruh Ti dalam penguatan presipitasi paduan Al-5.1Zn-1.8Mg-0.4Ti (% berat) pada berbagai temperatur. Paduan ini dibuat dengan proses squeeze casting. Kemudian dilakukan homogenisasi pada temperatur 400 oC selama 4 jam dan laku pelarutan pada 440 oC selama 1 jam yang dilanjutkan dengan pencelupan air hingga temperatur ruang. Penuaan dilakukan pada temperatur 90, 130 dan 200 oC selama 200 jam. Untuk mengetahui respon penuaan, dilakukan pengujian kekerasan Rockwell, sementara itu perubahan struktur mikro diamati dengan menggunakan Mikroskop Optik dan Scanning Electron Microscope (SEM) - Energy Dispersive Spectroscopy (EDS). Hasil penelitian menunjukkan bahwa kekerasan tertinggi dihasilkan setelah penuaan di temperatur 90 oC, bahkan pada temperatur ini, kekerasan terus meningkat setelah 200 jam. Semakin tinggi temperatur penuaan, semakin rendah kekerasan puncak yang dihasilkan, tapi waktu yang dibutuhkan untuk mencapai kekerasan puncak akan berkurang. Penambahan Ti diketahui dapat menahan penguatan dengan memperlambat kinetika presipitasi melalui penurunan jumlah kekosongan kompleks zat terlarut. Urutan presipitasi yang terbentuk adalah GP zone  ƞ?  ƞ (MgZn2).

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Al-Zn-Mg alloys (7xxx series Al alloys) have been widely used in many applications, especially in aerospace industry because of their high strength and low density. These alloys are commmonly hardened upon ageing treatment, in which diffusion of Zn and Mg atoms from super saturated solid solution results in formation of metastable precipitates. To further increase the strength of the alloys, Ti is added to decrease the grain size. The objective of this study is to investigate the role of Ti in the precipitation strengthening of Al-5Zn-1.8Mg-0.4Ti (wt.%) alloy.

The alloy was fabricated by squeeze casting process. Then, the alloy was homogenized at 400 oC for 4 hours. Subsequent solution treatment was employed at 440 oC for 1 hour and followed by water quenching to room temperature. The ageing was conducted at 90, 130 and 200 oC for 200 hours. The ageing response was followed by Rockwell hardness testing, while the microstructural evolution was observed by using Optical Microscope (OM) and Scanning Electron Microscope (SEM) - Energy Dispersive Spectroscopy (EDS).

The results showed that the highest hardness was achieved after ageing at 90 oC, and even at this temperature, the hardness remained increase after 200 h of ageing. The higher the ageing temperature, the lower the achieved peak hardness but the time needed to peak hardness reduced. Addition of Ti retarded the strengthening by slowering kinetics of precipitation through decreasing number of solute-vacancy complexes. The suggested major precipitation sequence was GP zones  ƞ?  ƞ (MgZn2)."

"[ABSTRAKKomposit nano Al A356 berpenguat partikel Al2O 3 berpotensi untuk meningkatkan kekuatan sifat mekanis tanpa mengorbankan keuletan pada matriks. Pada penelitian ini dilakukan variasi penambahan fraksi volume dari partikel nano Al2O 3 sebesar yaitu 0.1%, 0.2%, 0.5%, 1%, dan 1,2%. Untuk meningkatkan kemampubasahan dari Al2O 3 pada Al A356 ditambahakn Mg sebesar 10%. Hasil penelitian menunjukkan bahwa komposit Al A356/Al2O 3 dengan 0.5% Vf memiliki sifat mekanis yang lebih baik daripada yang lain. Nilai kekuatan tariknya mencapai 140,3 MPa lalu elongasinya sebesar 9,563% dan kekerasannya mencapai 46,2 HRB. Akan tetapi nilai mekanis dari kekuatan tarik masih dibawah dari Al A356 As cast maupun Al 356. Fenomena ini disebabkan karena adanya porositas dan persebaran partikel nano yang tidak merata.ABSTRACTAluminium A356 nano composite reinforced with Al2O 3 particle have a potential to increase mechanical properties while maintaining good ductility. In this study, the addition %Vt variation of Al2O 3. Variation used is 0.1%, 0.2%, 0.5%, 1%, dan 1,2%. To improve wettability of Al2O 3 in Al A356 addes 10% Mg. The results showed that the composite Al A356 / SiC 0,5% Vf have better mechanical properties than others. The ultimate tensile strength reach 140.3 MPa with 9.56% elongation. Hardness value reach 46,2.1 HRB. However, the value of ultimate tensile strength is still below the mechanical Al A356 As cast and Al 356. This phenomenon is due to the porosity and bad particle dispersion.;Aluminium A356 nano composite reinforced with Al2O 3 particle have a potential to increase mechanical properties while maintaining good ductility. In this study, the addition %Vt variation of Al2O 3. Variation used is 0.1%, 0.2%, 0.5%, 1%, dan 1,2%. To improve wettability of Al2O 3 in Al A356 addes 10% Mg. The results showed that the composite Al A356 / SiC 0,5% Vf have better mechanical properties than others. The ultimate tensile strength reach 140.3 MPa with 9.56% elongation. Hardness value reach 46,2.1 HRB. However, the value of ultimate tensile strength is still below the mechanical Al A356 As cast and Al 356. This phenomenon is due to the porosity and bad particle dispersion.;Aluminium A356 nano composite reinforced with Al2O 3 particle have a potential to increase mechanical properties while maintaining good ductility. In this study, the addition %Vt variation of Al2O 3. Variation used is 0.1%, 0.2%, 0.5%, 1%, dan 1,2%. To improve wettability of Al2O 3 in Al A356 addes 10% Mg. The results showed that the composite Al A356 / SiC 0,5% Vf have better mechanical properties than others. The ultimate tensile strength reach 140.3 MPa with 9.56% elongation. Hardness value reach 46,2.1 HRB. However, the value of ultimate tensile strength is still below the mechanical Al A356 As cast and Al 356. This phenomenon is due to the porosity and bad particle dispersion., Aluminium A356 nano composite reinforced with Al2O 3 particle have a potential to increase mechanical properties while maintaining good ductility. In this study, the addition %Vt variation of Al2O 3. Variation used is 0.1%, 0.2%, 0.5%, 1%, dan 1,2%. To improve wettability of Al2O 3 in Al A356 addes 10% Mg. The results showed that the composite Al A356 / SiC 0,5% Vf have better mechanical properties than others. The ultimate tensile strength reach 140.3 MPa with 9.56% elongation. Hardness value reach 46,2.1 HRB. However, the value of ultimate tensile strength is still below the mechanical Al A356 As cast and Al 356. This phenomenon is due to the porosity and bad particle dispersion.]"