Search results for " cutting"
showing 10 items of 59 documents
Orthogonal and Oblique Cutting Mechanics
2008
This chapter provides the engineering knowledge and modelling techniques applied in description of the material behaviour in the cutting zone resulting in chip formation and its separation from the bulk material. Geometrical and kinematical characteristics of orthogonal and oblique cutting models are classified and specified. Forces acting on the cutting tools and their measurement methods for several machining operations, such as turning, milling, drilling, boring and grooving, are presented. Moreover, forces acting in the cutting zone and their resolution on the shear plane and the rake and flank faces, along with stress distributions, are presented. The chapter highlights how components …
The influence of laser beam-width and focusing angle about the precision of cutting metallic materials
2005
To realize a high precision cutting operation, we must know the position and pointing of the beam axis- which are defined in accordance with ISO, by the centers of gravity of energy density distributions at different distances from the exit lens of laser. The angle of focalization must be related at least with; material width, beam energy, cutting speed, precision requirements and workpiece destination. Authors have realized experimental set-up for simultaneous measurement of energy density distributions, correlated with the mentioned working parameters. Besides the geometrical details, the authors studied also the influence of different values of beam density, about the zone affected by he…
Experimental Study of the Laser Cutting Process on 1C45 - 3 mm Steel
2014
The Paper Presents the Measurement Systems Analysis, System Capability and Optimization of a Laser Cutting System for 3 Mm Alloy Steel. for the Measurement System Analysis and System Capability the Data was Introduced in a Excel Sheet which was Designed According to QS9000 Standard (Measurement System Analysis) to Calculate the Measuring System Repeatability, Reproducibility and Capability. Design of Experiment (DOE) was Used for Process Optimization the Optimization was Conducted in an Operational Manufacturing Environment and was Based on the Design of a 25 Full Factorial Experiment. the Laser Parameters (input) were Feed Rate v, Gas Pressure p, Power P, Frequency F and Efficiency R while…
Effect of Cutting Size and Basal Heat on Rooting of Micromeria fruticulosa Stem Cuttings
2017
Micromeria fruticulosa (Bertol.) Grande is a small pulviniform shrub, belonging to the Labiates, and characterized by twisted stems and pink-purple flowers. Endemic to Campania and Sicily (Italy), M. fruticulosa grows from sea level to 600 m altitude. This specie might be considered an excellent native plant for landscape purposes in Mediterranean areas because of its long flowering period, extending from November to June, and its tolerance to heat and drought. The exploitation of wild plants for ornamental purposes implies knowledge on the factors influencing the propagation methods. Root development of stem cuttings of M. fruticulosa was investigated in relation to basal heat and cutting …
Thin film growth into the ion track structures in polyimide by atomic layer deposition
2017
Abstract High-aspect ratio porous structures with controllable pore diameters and without a stiff substrate can be fabricated using the ion track technique. Atomic layer deposition is an ideal technique for depositing thin films and functional surfaces on complicated 3D structures due to the high conformality of the films. In this work, we studied Al2O3 and TiO2 films grown by ALD on pristine polyimide (Kapton HN) membranes as well as polyimide membranes etched in sodium hypochlorite (NaOCl) and boric acid (BO3) solution by means of RBS, PIXE, SEM-EDX and helium ion microcopy (HIM). The focus was on the first ALD growth cycles. The areal density of Al2O3 film in the 400 cycle sample was det…
Some observations on metal cutting with reference to the mechanical characteristics of working materials
1972
The hypothesis of the minimum work of Merchant is applied to materials with different yield points in traction and in simple compression on the assumption that these materials yield in accordance with the paraboloid yield-criterion. The experimental data obtained from cutting tests like those described in this paper may apparently be in good agreement with theoretical results. But closer examination reveals that the values of the shear angle φ depend largely on the cutting speed and on the feed p. r. All relationship between φ and (λ — γ) (difference between the friction angle on the rake face and the rake angle) must therefore take in account the influence of the above variables.
Plenērs kā caurviju prasmes veicinoša mācību metode
2022
Plenērs kā mācību metode un mācību vide, kā izglītojošs un mērķcentrētu prasmju attīstošs aktivitāšu kopums tradicionāli tiek saistīts ar vizuālās mākslas jomu un nozarēm. Lai veicinātu plenēra, kā ārpustelpu mācību metodes un vides aktualitāti dažādās mācību jomās nepieciešams klasificēt caurviju prasmju metožu kopumu. Izveidot ieteikumus un starpnozaru, starpdisciplinārus mācību metožu moduļus ieteicamus skolotājiem un izglītojošu pasākumu kuratoriem Fenomenoloģiska pētījuma ietvaros veikta situācijas izpēte, daudzveidīgu brīvdabas aktivitāšu pieredzes apkopojums un analīze. Definēti daudzveidīgi kognitīvās spējas stimulējoši mācību stratēģijas moduļi , kuri demonstrē caurviju prasmes iet…
Basal heat improves adventitious root quality in Plumeria (Plumeria rubra L.) stem cuttings of different sizes
2014
Root development of hardwood cuttings of Plumeria rubra was investigated in relation to basal heat and the size of cuttings. Terminal cuttings of a clone grown in Sicily were trimmed to various lengths, ranging from 10 to 26 cm. To verify the cutting rooting response to basal heat, half of the cuttings were placed on a basal heated bench (28 ± 3°C, constant temperature) while the remaining were placed on an unheated bench (16-18°C during the night and 20-22°C during the day). Percent rooting and cutting survival were not affected by basal heat and cutting length. However, basal heat positively affected number of roots, length of longest root and bud growth. Increases in the length of the cu…
Researches Regarding Optimising the Contouring Precision of CNC Laser Cutting Machines
2014
This paper presents some experimental researches regarding the manufacturing accuracy of a profiling machine together with an approach to eliminate the positioning and contouring errors. A mathematical model based on transfer functions is used as starting approach in order to tune the feed drives of the machine. The accuracy of the profiling machine is tested before and after the tuning process, in order to validate the proposed approach. There are unfolded both positioning tests along one axis and contouring tests on two axes.
Improving the Manufacturing Accuracy of the Profiling Machines
2010
Abstract This paper presents the results of theoretical and experimental researches carried out with regard to the optimization of the dynamic behavior of a CNC laser cutting machine, in terms of cutting precision, for the case of flat metallic parts whose contours comprise right angles and which a profiling machine has to process continuously, without stopping in the corner points. It is aimed especially at detailing the influence of the numerical control equipment's setup on the size of the contouring errors and on the smoothness of the movement, factors that have a direct influence on the accuracy and that have been less addressed until now. The theoretical researches indicate that it is…