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Aluminium silicon alloy (AlSic) matrix composite reinforced with aluminium nitride (AlN) particle is a new generation material for automotive and aerospace application. This material has low density, light weight, high strength, high hardness and stiffness. Metal Matrix Composit (MMC) material is one of the advanced materials which have good future prospects. This paper presents the study of tool wear and surface roughness investigation when milling AlSi/AlN Metal Matrix Composite using uncoated carbide cutting tool. The volume of AlN reinforced particle was 10%. The milling process was carried out under dry cutting condition. The uncoated carbide insert parameters used were cutting speed of (250-750 m/min), while feed rate and depth of cut were kept constant at 0.15 mm/tooth of 0.3mm respectively. The Sometech SV-35 video microscope system and Mitutoyo surface roughness tester were used for tool wear measurements and surface roughness respectively. The results revealed that the tool wear increases with cutting speed (450 m/min). While at high cutting speed, the surface finish improves. It was found that the cutting speed of 750m/min was optimum condition for obtaining smooth finish and longer tool life. Keywords: AlSi/AlN Metal Matrix Composite milling process, tool wear, and surface roughness, uncoated cemented carbide tool

One of the crucial stages in fabrication of WC-Co composite is sintering process. Inappropriate sintering state, especially sintering temperature will lead to an abnormal grain growth and thus reduce the mechanical properties of the sintered parts. Sintering atmosphere also plays a big role in oxidation, carburizing, decarburizing and nitriding on the surface of sintered parts. Prevention of any unwanted process during sintering is demanded to maintain the performance of WC-CO composites without any by-products. In this work, the effect of different sintering atmosphere and sintering temperatures was studied on the mechanical properties of WC-Co composites. 95% nitrogen (N2) mixed with 5% hydrogen (H2) gases was used as sintering atmosphere in a tube furnace whereas vacuum atmosphere was carried out in vacuum furnace. The sintering process was conducted at 1300ºC and 1400ºC, respectively. Higher relative density, hardness and transverse rupture strength (TRS) were observed on the sintered parts. Sintering under N2-H2 atmosphere exhibited better mechanical properties. Low mechanical properties observed in vacuum atmosphere was probably due to over-sintering which led to grain growth activities and formation of ηphase.

Aluminum silicon (Al/Si) alloy, a metal matrix composite (MMC), is widely used in various industrial sectors, such as transportation, domestic equipment, aerospace, military, and construction. Al/Si alloy is a matrix composite reinforced with aluminum nitride (AlN) particle and transformed into a new-generation material for automotive and aerospace applications. AlN material is an advanced material characterized by light weight, high strength, and high hardness and stiffness, which makes it suitable for various future applications. However, its high ceramic particle reinforcement and the irregular nature of these particles along the matrix material make it a low density material. This low density is the main cause of problems during machining of this material. This paper studies tool wear in milling AlSi/AlN metal matrix composite by using an uncoated carbide cutting tool. The volume of AlN reinforced particle was 10%. The milling process was carried out under dry cutting conditions. The uncoated carbide insert parameters used were the following: cutting speed of 230 m/min to 370 m/min, feed rate of 0.4, 0.6, and 0.8 mm/tooth, and a corresponding depth of cut (DOC) of 0.3, 0.4, and 0.5 mm, respectively. Sometech SV-35 video microscope system was used for tool wear measurements. Results revealed that tool wear increases at 230 m/min cutting speed, 0.4 mm/tooth feed rate, and 0.3 mm depth of cut. The medium cutting speed, specifically the 300 m/min cutting speed, 0.4 mm/tooth feed rate, and 0.5 mm DOC, is the optimum condition for a longer tool life (82.94 min) and is ideal for cutting AlSi/AlN MMCs.