S. Sai Venkatesh, T. A. Ram Kumar, A. P. Blalakumhren, M. Saimurugan and K. Prakash Marimuthu
Tool wear influences tool life, machining cost, and most importantly the machining quality. Thus a quantitative study of cutting forces is essential for tool life estimation and tool condition monitoring. Initially, experimental methods and analytical methods were used to study cutting forces. D’Mello et al . [ 1 ] investigated the effects of flank wear, cutting parameters, and tool vibrations on the surface roughness during high-speed turning of Ti–6Al–4V. Ning et al . [ 2 ] devised a set of turning experiments with tool inserts having
Milon Selvam Dennison, Sivaram N M, Debabrata Barik and Senthil Ponnusamy
In the present day manufacturing environment, machining operations are inevitable in producing finished products. In any machining operation involving metal cutting, the usage of lubricants plays a vital role in maintaining favourable manufacturing conditions [ 1 ]. The favourable manufacturing conditions are a combination of certain process parameters and conditions, due to which best quality machine components are produced [ 2 , 3 ]. Above 95% of gross energy sustained to the machine tool is changed over into heat, because of the relative
 B.Yordanov, Heat Treatment of Tool Steel X210CR12 After Modification With Nanodispersed Si3N4 , Journal of the University of Chemical Technology and Metallurgy, 46, 4 ( 2011), 423-426.
 FV Anghelina, V Bratu, IN Popescu, Estimating the stacking faults of high alloyed steels, The Scientific Bulletin of Valahia University 8(11) (2013), 7-11.
 I.N. Popescu, D Bojin, I. Carceanu, G. Novac, F.V. Anghelina, Morphological And Structural Aspects Using Electronic Microscopy And Image Analysis Of Iron
to determine the amount of energy absorbed during fracture by a material. It is also known as the Charpy V-notch test. This absorbed energy is a measure of a given material notch toughness and acts as a tool to study temperature-dependent ductile–brittle transition. The value in Table 1 shows the ceramic material alumina which brings the strength and improves the impact strength percentage.
Percentage of Change in Impact Strength.
Impact Strength (nm)
% Change in Impact Strength
LM25 + 5% Zn
Chatter is a self-excited vibration that occurs if the chip width is too large with respect to the dynamic stiffness of the system. Variable forces generated during the machining operation lead to vibrational excitation of the tools and workpiece, and as a result, the surface of the workpiece becomes wavy. In the next machining stage, if the generated wavy surface is not in phase with the wavy surface of the previous stage, the thickness of the chip becomes variable and it will lead to a change in the shear force. The change in the shear
when the AA7075 alloy is placed on the advancing side [ 6 ]. The welds that are fabricated using straight tool profiles have no defects, while the tapered tool profiles cause tunnel at the bottom of joints [ 7 ]. Structurally, transformation occurs in dissimilar friction stir weld of AA5083- O and AA6082-T6 aluminum alloys when the weld is anodized in H 2 SO 4 solution [ 8 ]. Effects of the sleeve plunging speed on the microstructure and lap shear failure load of the dissimilar 6063/5083 joints were discussed [ 9 ]. In the FSW process, two different grade aluminum
Drilling is a cutting process that uses a drill bit to cut a circular profile in workpiece. Forces acting on the drill bit reduce its life expectance. Analysis of forces acting on the drill bit during drilling prevents the tool from failing prematurely because of wear and excess feed rate. Excess feed rate can induce excessive internal stress on both the tool and workpiece. This paper aims to study the effects of reaction force acting on a drill bit during drilling of Al6061-T6. A numerical finite element simulation study is performed with commercially available software called Abaqus. Simulation results depend on the right choice of material property such as Johnson–Cook material property and Johnson–Cook damage property. Validation of material property is achieved by comparison of experimental results with simulative results. Reaction force acting against the drill bit during drilling is compared.
Mihǎiţǎ Nicolae Ardeleanu, Simona Mihai, Ruxandra Vidu, Emil Mihai Diaconu and Ileana Nicoleta Popescu
A microfluidic device designated for measurement of fluidic flows with different viscosity, necessary within trapping/realising of cells/particles system has been developed. We use a new concept as Microfluidic Pulse Width Modulation (MPWM) for controlling transport of a single cell/particle. The image processing helped the nano-hydraulic volumes/flow rates measurement, through tracking inovative methods with the purpose to build a flow sensor. The device open an unique opportunitie for single cell study with applications in biomedical devices, tools for biochemistry or analytical systems.
Nastase-Dan Ciobota, Gheorghe Ion Gheorghe and Veronica Despa
Additive Manufacturing (AM) concerns all classes of materials – polymers, metals, ceramics and glasses as well. For this reason, AM is in the focus of material scientists from all branches. Leaders of the industry realize that the possibilities of 3D printing are endless, and that these possibilities need ways and means to be taken full advantage of. Today, aerospace engineers are using the fused deposition modeling (FDM) method for rapid prototyping, part manufacturing, and tooling. They are followed by leaders and engineers from industry (industrial machines, motor vehicles, consumer products, medical/dental) but also from academic institutions and government/military.