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This paper represents the results of application of molybdenum disulfide nanofluid as coolant in milling process of Al8Si3Cu aluminum alloy. During the experiments, the effects of dry, flood-cooling and MoS2 nanofluid cooling conditions on cutting temperature and surface roughness of work-piece in milling process were investigated. The cutting speed, feed rate and depth of cut were considered as the input parameters in the range between 80 and 315 mm/min, 80-160 m/min and 0.2 to 0.8 mm, respectively. It was found that the application of molybdenum disulfide nanofluid as a lubricant significantly reduced the surface roughness of work-piece in end milling process. The present of nanoparticles as additives in the coolant was proved to reduce the deterioration of surface quality caused by activated adhesion during cutting operation. This is confirmed by reduction in cutting temperature in milling using MoS2 nanofluid as compared with dry and flood cooling milling processes. The lowest surface roughness was found to be equal to 0.173 µm at cutting speed of 80 m/min, feed rate of 80 mm/min, and depth of cut of 0.2 mm in end milling process using MoS2 nanofluid cooling condition. Based on the results, the maximum reduction in surface roughness in end milling process of Al8Si3Cu aluminum alloy with application of MoS2 nanofluid lubrication in comparison to dry and flood cooling conditions were recorded as 91 and 87.7%, respectively. In addition, cutting temperatures were reduced in milling process with MoS2 nanofluid lubrication by 56.8% and 35.3% as compared with that of dry and flood cooling conditions, respectively. [ABSTRACT FROM AUTHOR]

Thermal spread pattern is an effective parameter on laser workability of materials. The thermal behavior pattern of nanocomposites containing carbon nanotubes (CNTs) mostly depends on CNTs alignment and their dispersion within the polymer matrix. This phenomenon makes different their laser workability. The present work is trying to investigate experimentally the influence of alignment and dispersion pattern of CNTs within the polycarbonate (PC) and polystyrene (PS) matrixes on laser cutting workability. In order to reach this purpose, in the first step, the injection and compression molded nanocomposites by different CNT loadings were produced, and then they were cut by laser in different conditions. The transmission electron microscope (TEM) was used to explore the CNTs structure with in the polymer. The results show that the CNTs loading, alignment and dispersion are the effective parameters on outputs. The minimum amounts of kerf width, heat affected zone, burr and kerf taper angle were obtained for compression molded samples. The findings also reveal the CNTs alignment and dispersion pattern are more effective than the CNT loading on kerf width and burr for both of PS and PC polymers matrix. Improving the conditions in lower power and higher cutting velocity is another important finding. [ABSTRACT FROM AUTHOR]

ABSTRACT In this work, the electrical surface conductivity enhancement of injection-molded multiwalled carbon nanotube (MWCNT)/poly(methyl methacrylate) (PMMA) nanocomposite by using CO2 laser processing was studied. Variable input factors are considered as MWCNT concentration (in three levels 0.5, 1, and 1.5 wt %), the laser feed angle with the flow direction (in five levels 0°, 30°, 45°, 75°, and 90°), and the cavity machining method that were produced by electrodischarge machining and computer numerical control milling with finishing process. The studies show that the irradiation of laser and utilization of covering gas could enhance the CNT-CNT contacts and the surface electrical conductivity. The morphology of laser-irradiated surface by using scanning electron microscope certified that the conductive network generated from CNT-CNT contacts can transfer the electrical current. The findings clearly show that the laser feed angle with the flow direction influenced the electrical conductivity. The maximum conductivity (∼ 5.310 × 10−4 S) was observed at 75°. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42671. [ABSTRACT FROM AUTHOR]