scholarly journals Investigation of Two-Dimensional Ultrasonic Surface Burnishing Process on 7075-T6 Aluminum

2021 ◽  
Vol 34 (1) ◽  
Author(s):  
Zhenyu Zhou ◽  
Qiuyang Zheng ◽  
Cong Ding ◽  
Guanglei Yu ◽  
Guangjian Peng ◽  
...  

AbstractA novel two-dimensional ultrasonic surface burnishing process (2D-USBP) is proposed. 7075-T6 aluminum samples are processed by a custom-designed 2D-USBP setup. Parameter optimization of 2D-USBP is conducted to determine the best processing strategy of 7075-T6 aluminum. A uniform design method is utilized to optimize the 2D-USBP process. U13(133) and U7(72) tables are established to conduct parameter optimization. Burnishing depth, spindle speed, and feed rate are taken as the control parameters. The surface roughness and Vickers hardness are taken as the evaluation indicators. It establishes the active control models for surface quality. Dry wear tests are conducted to compare the wear-resistance of the 2D-USBP treated sample and the original sample. Results show that the machining quality of 2D-USBP is best under 0.24 mm burnishing depth, 5000 r/min spindle speed, and 25 mm/min feed rate. The surface roughness Sa of the sample is reduced from 2517.758 to 50.878 nm, and the hardness of the sample surface is improved from 167 to 252 HV. Under the lower load, the wear mechanism of the 2D-USBP treated sample is mainly abrasive wear accompanied by delamination wear, while the wear mechanism of the original sample is mainly delamination wear. Under the higher load, the accumulation of frictional heat on the sample surface transforms the wear mechanisms of the original and the 2D-USBP treated samples into thermal wear.

Author(s):  
Tyler L. Perry ◽  
Dirk Werschmoeller ◽  
Xiaochun Li ◽  
Frank E. Pfefferkorn ◽  
Neil A. Duffie

The objective of this work was to improve our understanding of pulsed laser micropolishing (PLμP) by studying the effects of laser pulse length and feed rate (pulses per millimeter) on surface roughness. PLμP experiments were conducted with a multimode neodymium-doped yttrium aluminum garnet (Nd:YAG) laser (1064 nm wavelength) that was focused down to approximately 50 μm diameter and scanned over the stationary workpiece surface. Simulation results presented here and previous work suggest that longer laser pulses result in smoother surfaces. Results on microfabricated nickel samples using laser pulse durations of 300 ns and 650 ns test this hypothesis. Polishing with 300 ns and 650 ns pulse durations results in an average surface roughness of 66 nm and 47 nm, respectively; reductions of 30% and 50% compared with the original surface. Furthermore, PLμP is shown to introduce a minor artifact on the sample surface whose spatial frequency (1/mm) is directly related to the laser feed rate (pulses/mm).


2013 ◽  
Vol 315 ◽  
pp. 241-245 ◽  
Author(s):  
Ali Davoudinejad ◽  
M.Y. Noordin ◽  
Danial Ghodsiyeh ◽  
Sina Alizadeh Ashrafi ◽  
Mohsen Marani Barzani

Hard turning is a dominant machining operation performed on hardened materials using single-point cutting tools. In recent years, hard turning operation has become more and more capable with respect to various machinability criteria. This work deals with machinability of hardened DF-3 tool steel with 55 ±1 HRC hardness at various cutting conditions in terms of tool life, tool wear mechanism and surface roughness. Continuous dry turning tests were carried out using coated, mixed ceramic insert with honed edge geometry. Two different cutting speeds, 100 and 210 m/min, and feed rate values of 0.05, 0.125 and 0.2 mm/rev were used with a 0.2 mm constant depth of cut for all tests. Additionally scanning electron microscope (SEM) was employed to clarify the different types of wear. As far as tool life was concerned, best result was achieved at lowest cutting condition whereas surface roughness values decreased when operating at higher cutting speed and lower feed rate. Additionally maximum volume of material removed is obtained at low cutting speed and high feed rate. Dominant wear mechanism observed during the experiments were flank and crater wear which is mainly caused by abrasive action of the hard workpiece material with the ceramic cutting tools.


2020 ◽  
Vol 38 (8A) ◽  
pp. 1143-1153
Author(s):  
Yousif K. Shounia ◽  
Tahseen F. Abbas ◽  
Raed R. Shwaish

This research presents a model for prediction surface roughness in terms of process parameters in turning aluminum alloy 1200. The geometry to be machined has four rotational features: straight, taper, convex and concave, while a design of experiments was created through the Taguchi L25 orthogonal array experiments in minitab17 three factors with five Levels depth of cut (0.04, 0.06, 0.08, 0.10 and 0.12) mm, spindle speed (1200, 1400, 1600, 1800 and 2000) r.p.m and feed rate (60, 70, 80, 90 and 100) mm/min. A multiple non-linear regression model has been used which is a set of statistical extrapolation processes to estimate the relationships input variables and output which the surface roughness which prediction outside the range of the data. According to the non-linear regression model, the optimum surface roughness can be obtained at 1800 rpm of spindle speed, feed-rate of 80 mm/min and depth of cut 0.04 mm then the best surface roughness comes out to be 0.04 μm at tapper feature at depth of cut 0.01 mm and same spindle speed and feed rate pervious which gives the error of 3.23% at evolution equation.


2021 ◽  
pp. 089270572199320
Author(s):  
Prakhar Kumar Kharwar ◽  
Rajesh Kumar Verma

The new era of engineering society focuses on the utilization of the potential advantage of carbon nanomaterials. The machinability facets of nanocarbon materials are passing through an initial stage. This article emphasizes the machinability evaluation and optimization of Milling performances, namely Surface roughness (Ra), Cutting force (Fc), and Material removal rate (MRR) using a recently developed Grey wolf optimization algorithm (GWOA). The Taguchi theory-based L27 orthogonal array (OA) was employed for the Machining (Milling) of polymer nanocomposites reinforced by Multiwall carbon nanotube (MWCNT). The second-order polynomial equation was intended for the analysis of the model. These mathematical models were used as a fitness function in the GWOA to predict machining performances. The ANOVA outcomes efficiently explore the impact of machine parameters on Milling characteristics. The optimal combination for lower surface roughness value is 1.5 MWCNT wt.%, 1500 rpm of spindle speed, 50 mm/min of feed rate, and 3 mm depth of cut. For lower cutting force, 1.0 wt.%, 1500 rpm, 90 mm/min feed rate and 1 mm depth of cut and the maximize MRR was acquired at 0.5 wt.%, 500 rpm, 150 mm/min feed rate and 3 mm depth of cut. The deviation of the predicted value from the experimental value of Ra, Fc, and MRR are found as 2.5, 6.5 and 5.9%, respectively. The convergence plot of all Milling characteristics suggests the application potential of the GWO algorithm for quality improvement in a manufacturing environment.


2021 ◽  
Vol 3 (2) ◽  
Author(s):  
Shahin Haghnazari ◽  
Vahid Abedini

AbstractThis paper presents an effort to model the process parameters involved in turning of alloy steel AISI 4340 workpiece material with Al2O3 and CuO hybrid nanofluids using the minimum quantity lubrication (MQL) method. In this paper, the effect of mixing two nanoparticles (Al2O3 and CuO) with different weight percent in environmentally friendly water-based cutting fluid, the rotational speed, and the feed rate has been investigated on the surface roughness and the machining forces using the response surface method. The results of the experiments show that the hybrid nanofluid containing 0.75 CuO with 0.25 Al2O3 has the best output for the machining forces and the surface roughness. Also, in the best composition of the nanoparticles (0.75 CuO with 0.25 Al2O3), the lowest value of machining forces has been achieved at a feed rate of 0.08 mm per revolution and the rotational speed 1000 rpm as well as the lowest value of the surface roughness at a feed rate of 0.08 mm per revolution and the rotational speed 710 rpm.


2001 ◽  
Vol 432 ◽  
pp. 69-90 ◽  
Author(s):  
RUDOLPH A. KING ◽  
KENNETH S. BREUER

An experimental investigation was conducted to examine acoustic receptivity and subsequent boundary-layer instability evolution for a Blasius boundary layer formed on a flat plate in the presence of two-dimensional and oblique (three-dimensional) surface waviness. The effect of the non-localized surface roughness geometry and acoustic wave amplitude on the receptivity process was explored. The surface roughness had a well-defined wavenumber spectrum with fundamental wavenumber kw. A planar downstream-travelling acoustic wave was created to temporally excite the flow near the resonance frequency of an unstable eigenmode corresponding to kts = kw. The range of acoustic forcing levels, ε, and roughness heights, Δh, examined resulted in a linear dependence of receptivity coefficients; however, the larger values of the forcing combination εΔh resulted in subsequent nonlinear development of the Tollmien–Schlichting (T–S) wave. This study provides the first experimental evidence of a marked increase in the receptivity coefficient with increasing obliqueness of the surface waviness in excellent agreement with theory. Detuning of the two-dimensional and oblique disturbances was investigated by varying the streamwise wall-roughness wavenumber αw and measuring the T–S response. For the configuration where laminar-to-turbulent breakdown occurred, the breakdown process was found to be dominated by energy at the fundamental and harmonic frequencies, indicative of K-type breakdown.


2010 ◽  
Vol 447-448 ◽  
pp. 51-54
Author(s):  
Mohd Fazuri Abdullah ◽  
Muhammad Ilman Hakimi Chua Abdullah ◽  
Abu Bakar Sulong ◽  
Jaharah A. Ghani

The effects of different cutting parameters, insert nose radius, cutting speed and feed rates on the surface quality of the stainless steel to be use in medical application. Stainless steel AISI 316 had been machined with three different nose radiuses (0.4 mm 0.8 mm, and 1.2mm), three different cutting speeds (100, 130, 170 m/min) and feed rates (0.1, 0.125, 0.16 mm/rev) while depth of cut keep constant at (0.4 mm). It is seen that the insert nose radius, feed rates, and cutting speed have different effect on the surface roughness. The minimum average surface roughness (0.225µm) has been measured using the nose radius insert (1.2 mm) at lowest feed rate (0.1 mm/rev). The highest surface roughness (1.838µm) has been measured with nose radius insert (0.4 mm) at highest feed rate (0.16 mm/rev). The analysis of ANOVA showed the cutting speed is not dominant in processing for the fine surface finish compared with feed rate and nose radius. Conclusion, surface roughness is decreasing with decreasing of the feed rate. High nose radius produce better surface finish than small nose radius because of the maximum uncut chip thickness decreases with increase of nose radius.


A two-dimensional homogeneous random surface { y ( X )} is generated from another such surface { z ( X )} by a process of smoothing represented by y ( X ) = ∫ ∞ d u w ( u – X ) z ( u ), where w ( X ) is a deterministic weighting function satisfying certain conditions. The two-dimensional autocorrelation and spectral density functions of the smoothed surface { y ( X )} are calculated in terms of the corresponding functions of the reference surface { z ( X )} and the properties of the ‘footprint’ of the contact w ( X ). When the surfaces are Gaussian, the statistical properties of their peaks and summits are given by the continuous theory of surface roughness. If only sampled values of the surface height are available, there is a corresponding discrete theory. Provided that the discrete sampling interval is small enough, profile statistics calculated by the discrete theory should approach asymptotically those calculated by the continuous theory, but it is known that such asymptotic convergence may not occur in practice. For a smoothed surface { y ( X )} which is generated from a reference surface { z ( X )} by a ‘good’ footprint of finite area, it is shown in this paper that the expected asymptotic convergence does occur always, even if the reference surface is ideally white. For a footprint to be a good footprint, w ( X ) must be continuous and smooth enough that it can be differentiated twice everywhere, including at its edges. Sample calculations for three footprints, two of which are good footprints, illustrate the theory.


2014 ◽  
Vol 590 ◽  
pp. 294-298
Author(s):  
Pichai Janmanee ◽  
Somchai Wonthaisong ◽  
Dollathum Araganont

In this study, effect of machining parameters and wear mechanism in milling process of mold steel AISI-P20 and AISI-1050, using 10 mm twin flute type end mill diameter. The experimental results found that characteristics of milling surfaces and wear of the mill end were directly influenced by changes of parameters for all test conditions. As a result, the quality of milling surfaces also changed. However, mould steels which had the good quality surface is AISI-1050, with roughnesses of 2.120 μm. Quality milling surfaces were milled by using the most suitable parameter feed rate of 45 mm/min, a spindle speed of 637 rpm and a cut depth level of 3 mm, for both grades. Moreover, material removal rate and duration of the milling process, the milling end mills affect wear of the edge in every bite when the feed rate is low, high speed and level depth of cut at least. It was found that limited wear less will affect the surface roughness (Ra) represents the good quality surface.


2010 ◽  
Vol 126-128 ◽  
pp. 885-890
Author(s):  
K.P. Somashekhar ◽  
N. Ramachandran ◽  
Jose Mathew

This work is on the preparation of microelectrodes for μ-EDM operation using μ-WEDG process. Electrodes of Ø500 μm are fabricated with various discharge energy machining conditions. Effects of gap voltage, capacitance & feed rate on the surface finish of the electrodes and overcut of the thus produced micro holes are investigated. The profile of microelectrodes is measured using surface roughness tester with 2μm stylus interfaced with SURFPAK software. The study demonstrated that for brass electrodes an arithmetic average roughness value as low as 1.7μm and an overcut of 3 µm could be achieved. The significant machining parameters are found using ANOVA. Surface of the produced microelectrodes are examined using Scanning Electron Microscope. μ-WEDG process parameters could be adjusted to achieve good surface integrity on microelectrodes. Experimental results showed that the surface roughness of microelectrodes depended primarily on feed rate of the electrode. The observations showed the clear and quantitative correlation existing between the micrometer level surface quality and process parameters. The resulting microelectrodes are found to be of exceptionally high quality and could be used for μ- EDM operation on different types of work materials.


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