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"Komposit matriks atau MMC's menawarkan masa depan yg baik,spesifik kekakuan (stiffnes) dan kekuatan meningkat relatif terhadap bhn tanpa penguatan walaupun sifat meakanik dpt dipengaruhi oleh kehadiran porositas dr prosesi pengecoran dengan stiring.Pengaruh dr penekanan isostatik panas (HIPping) pd porositas didlm paduan aluminium stir-cast A357/15 vol%Sic partikel MMC's telah diteliti.Empat perlakuan HIPping yg berbeda telah diselidiki dan hasilnya menunjukkan bahwa HIPping dengan kondisi 565oC/103 MPa/15 menit diikuti oleh 535oC/103MPa/2 jam adalah yg optimum.Pengujian 4 titik banding dengan takik tunggal dilakukan pd benda uji yg telah mengalami HIPping. Kekuatan bending telah meningkat secara signifcan krn berkurangnya porositas setelah kondisi HIPping ini di bandingkan bhn bakunya.Partikel penguat keramik yg dikombinasikan dengan paduan aluminium matrix composit dpt menyediakan kebutuhan antara penghematan berat(pengurangan berat) dan ketangguhan yg diperlukan."

"Paduan titanium-besi (Ti-Fe) diharapkan dapat digunakan di bidang presisi tinggi karena kekuatannya yang tinggi dan ketahanan terhadap korosi dengan tetap mempertimbangkan efisiensi ekonomi. Metalurgi serbuk (PM) dan proses Hot Isostatic pressing (HIP) digunakan untuk memanfaatkan laju difusi besi (Fe) yang sangat tinggi dalam titanium (Ti) untuk menghindari segregasi selama pemadatan dan untuk mencoba membuat paduan Ti-Fe yang homogen. Sifat mekanik dan kinerja korosi paduan Ti-Fe yang terbuat dari HIP yang mengandung proporsi Fe berbeda dievaluasi secara komprehensif. Metode yang digunakan meliputi uji tarik, uji energi impak Charpy, cyclic potentiodynamic polarization (CPP) dan electrochemical impedance spectroscopy (EIS). Hasilnya menunjukkan bahwa dengan meningkatnya kandungan Fe, tegangan tahan 0,2%, kekuatan tarik ultimate (UTS), dan tegangan patah paduan meningkat, namun perpanjangan dan energi serap pada tumbukan menunjukkan tren menurun, menunjukkan bahwa kekuatan mekanik meningkat tetapi paduannya menjadi lebih rapuh. Misalnya, UTS Ti-5%Fe mencapai 732MPa, atau 1,9 kali lipat dibandingkan CP-Ti. Secara umum, paduan Ti xFe menunjukkan ketahanan korosi yang unggul dibandingkan CP-Ti karena penghalusan butiran dan kinetika pertumbuhan lapisan oksidasi. Misalnya, resistensi perpindahan muatan Ti-5%Fe paling tinggi yaitu 2,68E+05 Ω∙〖cm〗^2, atau 2,3 kali lipat CP-Ti, diikuti oleh Ti-2%Fe. Namun peningkatan ketahanan korosi ini tidak sebanding dengan kandungan Fe melainkan terdapat rasio Ti-Fe yang optimal. Kombinasi sifat mekanik dan kinerja korosi membuktikan potensi yang baik dari paduan Ti-Fe.

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Titanium-iron (Ti-Fe) alloys are expected to be used in high-precision fields because of their high strength and corrosion resistance while taking into account economic efficiency. Powder metallurgy (PM) and the hot isostatic pressing (HIP) process was used to utilize the very high diffusion rate of iron (Fe) in titanium (Ti) to avoid the segregation during solidification and to try to make homogeneous Ti-Fe alloys. The mechanical properties and corrosion performance of Ti-Fe alloys made from HIP containing different proportions of Fe were evaluated comprehensively. The used methods included tensile test, Charpy impact energy test, cyclic potentiodynamic polarization (CPP) and electrochemical impedance spectroscopy (EIS). The results indicate that with the increase of Fe content, the 0.2% proof stress, ultimate tensile strength (UTS) and fracture stress of the alloys increase, but the elongation and absorbed energy on impact show decreasing trends, indicating that the mechanical strength increases but the alloys become more brittle. For instance, the UTS of Ti-5%Fe is reached 732MPa, or 1.9 times over CP-Ti. In general, Ti xFe alloys exhibit superior corrosion resistance compared to CP-Ti due to the grain refinement and oxidation film growth kinetics. For example, the charge transfer resistance of Ti-5%Fe is highest which is 2.68E+05 Ω∙〖cm〗^2, or 2.3 times over CP-Ti, followed by Ti-2%Fe. However, this increase in corrosion resistance is not proportional to the Fe content but there is an optimal Ti-Fe ratio. The combination of mechanical properties and corrosion performance evidence the good potential of Ti-Fe alloys."

"Machining of metal matrix composites gives the reader information on machining of MMCs with a special emphasis on aluminium matrix composites. Chapter 1 provides the mechanics and modelling of chip formation for traditional machining processes. Chapter 2 is dedicated to surface integrity when machining MMCs. Chapter 3 describes the machinability aspects of MMCs. Chapter 4 contains information on traditional machining processes and chapter 5 is dedicated to the grinding of MMCs. Chapter 6 describes the dry cutting of MMCs with SiC particulate reinforcement. Finally, chapter 7 is dedicated to computational methods and optimization in the machining of MMCs."

"The present work aims to improve the microstructure and hardness relatedproperties of age hardened Al6061-SiC reinforced composites produced by a two stage stir casting method. Three composites with2, 4, and 6wt. % (35-40μm) of SiC reinforcement are subjected tomicrostructural examination and hardness test at different locations to analysethe uniform distribution of the reinforcements in the matrix. As-castcomposites are solution-treated at 558°C, followed by an aging treatment conducted at 100, 150, and 200°C, during which peak hardness values are noted. The peak agedsamples are subjected to hardness and wear tests. In line with the objectives, ranges from 80-100% and 120-145% additional increase in hardnessvalues are observed over as-cast alloy during the aging treatment conducted at 100, 150 and 200°C, respectively. Lower temperature aging showssubstantial improvement in hardness and wear resistance over high temperatureaging in each respective group. Alsohigher weight percentages of reinforced composites show excellent wearresistance, due to the presence of eroded iron particles fromthe counter surface which is regarded as a beneficial effect during the wear test. The presence of SiC particles provides more sites for the nucleation of fineprecipitates. These fine precipitates hinder the movement of dislocation andthus increases hardness as well as wear resistance after the precipitation hardening treatment."

"The present work aims to improve the microstructure and hardness related properties of age hardened Al6061-SiC reinforced composites produced by a two stage stir casting method. Three composites with 2, 4, and 6wt. % (35-40?m) of SiC reinforcement are subjected to microstructural examination and hardness test at different locations to analyse the uniform distribution of the reinforcements in the matrix. As-cast composites are solution-treated at 558°C, followed by an aging treatment conducted at 100, 150, and 200°C, during which peak hardness values are noted. The peak aged samples are subjected to hardness and wear tests. In line with the objectives, ranges from 80-100% and 120-145% additional increase in hardness values are observed over as-cast alloy during the aging treatment conducted at 100, 150 and 200°C, respectively. Lower temperature aging shows substantial improvement in hardness and wear resistance over high temperature aging in each respective group. Also higher weight percentages of reinforced composites show excellent wear resistance, due to the presence of eroded iron particles from the counter surface which is regarded as a beneficial effect during the wear test. The presence of SiC particles provides more sites for the nucleation of fine precipitates. These fine precipitates hinder the movement of dislocation and thus increases hardness as well as wear resistance after the precipitation hardening treatment."

"Pure Al/SiC metal matrix composites (MMC) have been successful produced by the Lanxide process with different processing temperature for 8 hours. The process is simply without aid externally pressure. However, N2 oxygen free was flushed during the process. Molten pure Al has fully infiltrated to the preform with Sl/1% Mg at 750, 800, 850, 900 and 1000°C§ but infiltration did not occur to the preform with 3Vj'% Mg. Voids exist above the infiltrated preform in the systems with higher temperature (900 °C and 1000°C) for 8 hours. Such voids were not formed in the systems with low temperature. This paper described the investigation into the production of pure Al matrix composites, the eject of processing temperature will be investigated and the resulting will be fully characterised."