Experimental Investigation of the Magnetic Abrasive Finishing of SS310s

Magnetic abrasive finishing (MAF), an unconventional process, enhances the surface finish of a material. The current research focuses on its use with SS310s. The finite element analysis (FEA) result shows the effect of control parameters on the magnetic flux density. In FEA analysis, it was decided to maintain an air gap of 1.5-2 mm and a voltage of 10-20 V. A response surface methodology (RSM) desirability function is used to identify the optimal process parameters. Experiments are conducted for optimizing the process parameters like voltage, rotational speed, machining gap, mixing ratio, and mesh number to enhance the material removal rate (MRR) and surface roughness (Ra). A series of 62 experiments are conducted using optimized process parameters at different levels. Moreover, analysis of variance (ANOVA) is used to identify the percentage contribution of each process parameter in %ΔRa and MRR. From this, the mesh number of the abrasives plays an important role in the finishing process owing to the increased number of cutting edges and because of the uniform normal force (Fn) distribution. The optical microscopic image result and the wear test confirms that the surface finish of SS310s has been improved using MAF.

Comparative Study of Histological and Histochemical Image Processing in Muscle Fibre Sections of Broiler Chicken

Image processing of muscular fibre has significantly improved over the last decades, from light microscopy acquisition to virtual microscopy and from manual segmentation and fibre typing to automatic. The study aims to discuss main tools used in different histoenzymological image processing ‎phases of muscle fibre, which are consecutively, acquisition, segmentation and fibre typing and theirs ‎efficacy in morphometric parameters’ determination. Firstly, the acquisition, optical microscopic image with different magnifications ‎‎(x100, x200, x250 and x400) were compared with virtual slides digitized by Slide Scanner, in ‎muscle fibre sections, for cell number counting. Secondly, the segmentation, three software ‎‎(Fiji «Digitizing pen, Mouse», Image Pro Plus 10 -semi-automatic- and Cytoinformatics LLC -automatic-) were compared ‎for image segmentation quality and fibbers number determination. Thirdly, manual fibre typing with Fiji of segmented images using three software cited previously were performed to calculate the accuracy of morphometric parameter (CSA, perimeter and DMF). Results of acquisition showed that scanner slide have ‎a better resolution and detected a higher number of cells compared to optical microscopic with ‎different magnifications. For this latter, the processing can be performed only with an ‎acceptable resolution, where the number of cells is lesser, which requires unfortunately several ‎repetitions and exhausting work. Our findings regarding segmentation indicate that ‎Cytoinformatics LLC showed the best processing time and the highest quality followed by IP ‎and Fiji. For the last step, morphometric parameter calculation showed the best accuracy using Fiji followed by Cytoinformatics and finally by IP. ‎ The findings of this study suggest that Fiji (semi-automatic) showed the best quality/price ratio (open access software) for segmentation and fibre typing, but time consuming compared to ‎ Image Pro Plus 10 (semi-automatic) and Cytoinformatics LLC‎ (automatic) which are a paid service.

An Effective Method for Hybrid CNT/GNP Dispersion and Its Effects on the Mechanical, Microstructural, Thermal, and Electrical Properties of Multifunctional Cementitious Composites

This paper reports a study undertaken to achieve a compatible and affordable technique for the high-quality dispersion of carbon nanotubes (CNTs) and graphene nanoplatelets (GNPs) in an aqueous suspension to be used in multifunctional cementitious composites. In this research work, two noncovalent surfactants with different dispersion mechanisms (Pluronic F-127 (nonionic) and sodium dodecylbenzene sulfonate (SDBS) (ionic)) were used. We evaluated the influences of various factors on the dispersion quality, such as the surfactant concentration, sonication time, and temperature using UV-visible spectroscopy, optical microscopic image analysis, zeta potentials, and particle size measurement. The effect of tributyl phosphate (TBP) used as an antifoam agent was also evaluated. The optimum suspensions of each surfactant were used to produce cementitious composites, and their mechanical, microstructural, electrical, and thermal behaviors were assessed and analyzed. The best dispersed CNT+GNP aqueous suspensions using Pluronic and SDBS were obtained for concentrations of 10% and 5%, respectively, with 3 hours of sonication, at 40°C, with TBP used for both surfactants. The results also demonstrate that cementitious composites reinforced with CNT+GNP/Pluronic showed better mechanical performance and microstructural characteristics due to the higher quality of the dispersion and the increasing hydration rate. Composites prepared with an SDBS suspension demonstrated lower electrical and thermal conductivities compared to those of the Pluronic suspension due to changes in the intrinsic properties of CNTs and GNPs by the SDBS dispersion mechanism.

Effects of Probe Marks on Shear Test of Copper Ball Bonds in Two Pad Aluminum Thicknesses

This paper continues the work of reference [1], evaluating shear test results of Cu ball bonds over a variety of probe marks in two different pad aluminum (Al) thicknesses (0.8μm and 3μm). The presence of invasive probe marks on thick Al bond pads lowers certain shear force results.. Lower values of shear force imply reduced Cu bond reliability. Physical factors are investigated relating to poor intermetallic (IMC) formation in the Cu wirebond and bond shear force. Optical microscopic image analysis of Cu bonds, bond contact areas and Al “splash” are studied for correlation with the shear test results. Percent IMC coverage of bond contact areas decrease when invasive probe marks are present beneath the bond, which in turn may reduce the shear force. Probe mark features are studied to discover the characteristics of greatest influence on % IMC coverage and shear test values in each of the pad metal thicknesses.

Research on the Cutting Mechanism of High-Speed Precision Cutting TC4

In this paper, TC4 (Ti6Al4V) alloy has been cut at high speed minutely .Chip roots is extracted by rapid knife device. The optical microscopic image of the root chip is analyzed. The reasons why it is difficult to cut for TC4 alloy are firstly due to the low ability for heat transfer, while the second one maybe the cutting path is mainly the trans-granular failure which will consume more energy due to the coarse grains of TC4 alloy.