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This paper involves the study of nose radius effect and graphite addition during turning of AA 7075-ZrB 2 in-situ metal matrix composite. This in-situ method involves formation of reinforcements within the matrix by the chemical reaction of two or more chemical compounds that produces some changes in the matrix material within the vicinity. To form Zirconium Boride (ZrB 2 ) reinforcement in the matrix, two chemical salts of Potassium Tetrafluoroborate (KBF 4 ) and Potassium Hexafluorozirconate (K 2 ZrF 6 ) were added. After the fabrication of the test specimen, the specimen is subjected to turning in CNC high speed turning center. Four important parameters of tool nose radius, cutting speed, feed rate and depth of cut were taken for the present investigation. The in-situ composites were fabricated via-stir casting method followed by manually forge it. The fabricated specimen was turned using a 0.4 mm nose radius and 0.8 mm nose radius of PCD CNC inserts. After turning, the metal removal rate and surface roughness were measured and investigated. Based on the results obtained, it was observed that 0.8 mm nose radius inserted tool produced excellent machinability when compared to 0.4 mm nose radius. It was noted here that the higher rate of cutting speed, lower rate of feed rate and lower depth of cut combination process parameter produced excellent machinability. Further, the graphite reinforced in-situ AA 7075-3% ZrB 2 -1% Gr hybrid composite exhibited improved machinability than others samples of AA 7075 alloy, AA 7075-3%ZrB 2 in-situ composite. This was due to self-lubricant property of graphite particles. [ABSTRACT FROM AUTHOR]

Glass fiber reinforced polymer (GFRP) composite pipes are finding its increased applications in variety of engineering applications such as water softening plants, desalination plants, paper mill industry, marine water treatments. However, the users of FRP are facing difficulties to machine it, because of fiber de-lamination, fiber pull out, short tool life, matrix de-bonding and formation of powder like chips. The present investigation focuses on the effect of process parameters for surface roughness of glass fiber reinforced polymer (GFRP) composite pipes. Experiments were conducted based on the high speed turning centre (CNC) using poly-crystalline diamond (PCD) tool. The process parameters considered were cutting speed, feed, depth of cut, and work piece type (E-Glass mat and E-Glass woven specimen). Both pipes are fabricated using the filament winding process. The pipe consists of 70 percent epoxy polyester resin and 30 percent glass fiber. A comparative study has been undergone between the E-Glass woven and E-Glass mat fiber reinforced composite material. The mechanical properties were also conducted as per ASTM standards. Based on the results, it was observed that good machinability was obtained at lower cutting speed, feed rate, depth of cut for mat fiber reinforced GFRP pipe and at high cutting speed, lower feed rate, depth of cut for mat fiber reinforced GFRP pipe. [ABSTRACT FROM AUTHOR]

In aluminum matrix composites, presence of hard particles inside the matrix which causes tool wear, poor surface finish and high cutting forces while machining. This paper discusses the influence of graphite particles and cutting parameters on drilling characteristics of hybrid aluminum matrix composites (AMCs)—Al6063/6%Al 2 O 3p and Al6063/6%Al 2 O 3p /1%Gr p . The composites are fabricated using stir casting method. Experiments were conducted with TiN coated carbide tools and commercial carbide tools at various cutting speeds and feeds. Design of experiment of full factorial design is employed to analyze the drilling characteristics of these composites. Burr height and surface roughness of the drilled hole was investigated with special attention paid to the effects of graphite particles. The chips formed when machining graphitic composites are more discontinuous which led to better surface finish than non graphitic composite. [ABSTRACT FROM AUTHOR]

Recently, conventional aluminum alloys have replaced aluminum matrix composites due to its improved mechanical properties in many engineering applications. In this research hybrid aluminum matrix composite was manufactured for different combinations of Alumina and graphite by using stir casting method. Examination of hardness, compression tests, Impact strength and three point bending test of various manufactured hybrid AMCs revealed that mechanical properties were improved when AA 6063 alloy was reinforced with alumina and graphite particles. Mechanical characterization shows that the presence of 6% of alumina particles in the matrix improved Mechanical properties than other combination of alumina with matrix material. [ABSTRACT FROM AUTHOR]

Abstract: Automatic detection and extraction of buildings from high resolution satellite images has been an important research topic in the field of photogrammetry and remote sensing in recent years. Geospatial data like roads, buildings and rivers are the most critical feeds of a GIS database. But there are several problems to extract buildings properly, including different viewing angles, surrounding vegetation, shadows, and other objects which obscure the edges of the buildings which are being detected. This paper focuses on accurate and automatic extraction of urban area buildings from high resolution satellite imagery. The method first detects evidences of building existing by wavelet based watershed segmentation followed by a series of morphological operations and area analysis. Then the image is fed to a feed-forward back-propagation neural network system to distinguish small and bright buildings. The results of the performance evaluation show that the methodology performs well to extract buildings in complex environments. [Copyright &y& Elsevier]