Interdependence between stress, preferred orientation, and surface morphology of nanocrystalline TiN thin films deposited by dual ion beam sputtering Abstract. The effect of substrate bias and nitrogen flow rate on the TiAlN nanocoating structure and morphology has been investigated by using reactive unbalance DC magnetron sputtering. TiAlN nanocoating was deposited on the tungsten carbide insert tool and the structure and morphology were characterized by using XRD and AFM, respectively. The substrate bias was varied between 0 to -221 V and the nitrogen flow rate was varied between 30 to 72 sccm. The results showed that the structure of TiAlN nanocoating consisted of mainly (111) and (200) plane. The structure was significatly influenced by substrate bias in promoting finer crystal size and increased crystal plane spacing while the rms roughness of nanocoating was influenced by substrate bias and nitrogen flow rate.

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This paper presents the investigation of sand casting process in natural fibre reactions which is utilized kenaf fibre and empty fruit brunch fibre (EFB) in order to reinforce the silica sand casting mould. The investigation was carried out on selecting sand mould which mixture with natural fibre. As a result of surface roughness of kenaf fibre mixed with silica sand, empty fruit bunch fibre mixed with silica sand and silica sand for sand mould was evaluated. The comparison of these three types of sand mould for surface roughness are analysed by using portable surface roughness tester. Technique of mixing the natural fibre and silica sand was presented. The mould was prepared using similar volume of natural fibre between kenaf fibre and empty fruit bunch fibre. The ratio of natural fibre for two type of sand fibre mould using 100 g of natural fibre and 1 kg of silica sand. The third sand mould using only 3.3 kg of silica sand without mixed with natural fibre. Total weight of three type of sand mould is 3.3 kg. Besides, this investigation was employed with 3 mm to 5 mm length range of natural fibre and mixture mutually with silica sand. The addition of natural fibre in the sand casting mould was significantly absorbing the heat of molten metal to the surrounding. As a result, the utilization of kenaf fibre and EFB fibre for sand mould were significant on improving the surface roughness of casted LM6 material.

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A study on the surface morphology of sputtered TiAlN coatings is presented. The coatings were deposited by DC magnetron sputtering on tungsten carbide insert tools. The surface morphology was characterized by using Atomic Force Microscopy (AFM), and the surface roughness was indicated by RMS roughness value. It was observed that the TiAlN coating surface morphology was rough as the negative substrate bias and nitrogen flow rate are increased. The evolution of the sputtered TiAlN coatings surface morphology was due to the competition between particle diffusion and re-scattering effect during the sputtering process. At high negative substrate bias and nitrogen flow rate, the re-scattering effect was prominent, leading to the high roughness of the sputtered TiAlN coating surface.