Influence of Machining Parameters on 3D Surface Roughness of Powder Bushings

2016 ◽  
Vol 721 ◽  
pp. 378-382 ◽  
Author(s):  
Viktor Mironov ◽  
Pavels Stankevics ◽  
Artis Kromanis ◽  
Janis Lungevics

The paper presents the results on research of machining anti-friction bushings of lever brake systems of rail transport, wherein the bushings are made of powder material based on iron and copper. Powder composition contains Fe-C-Cu with Ni and Mo content of less than 0.3%, and with reduced phosphorus content. The porosity of the bushings were in the range of 15 – 20 %. The main objective of the work was to determine the optimal machining parameters, as well as to evaluate the quality of the machined surface. The bushing were machined with cutting speed in the range of 130 – 150 m/min. To assess the quality of the machined surfaces the 3D roughness parameters were used, which allow to asses the surface roughness in more accurate details. The microstructure of the samples indicated the presence of pores onto the machined surfaces. It was found that to improve the quality of the surface it is necessary to adjust the parameters of the powder processing of parts with high porosity in the direction of their reduction. Studies of the microstructure and morphology of chips showed that the shape and structure of the chip is highly dependent on the porosity of the material and its processing conditions.

2019 ◽  
Vol 27 (01) ◽  
pp. 1950081 ◽  
Author(s):  
CHUNHUI JI ◽  
SHUANGQIU SUN ◽  
BIN LIN ◽  
TIANYI SUI

This work performed molecular dynamic simulations to study the 2D profile and 3D surface topography in the nanometric cutting process. The least square mean method was used to model the evaluation criteria for the surface roughness at the nanometric scale. The result showed that the cutting speed was the most important factor influencing the spacing between the peaks, the sharpness of the peaks, and the randomness of the profile. The plastic deformation degree of the machined surface at the nanometric scale was significantly influenced by the cutting speed and depth of cut. The 2D and 3D surface roughness parameters exhibited a similar variation tendency, and the parameters Ra and Rq tended to increase gradually with an increase in the cutting speed and a decrease in the depth of cut. Finally, it is concluded that at the nanometric scale, the 3D surface roughness parameters could more accurately reflect the real surface characteristics than the 2D parameters.


Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 617 ◽  
Author(s):  
Ireneusz Zagórski ◽  
Jarosław Korpysa

Surface roughness is among the key indicators describing the quality of machined surfaces. Although it is an aggregate of several factors, the condition of the surface is largely determined by the type of tool and the operational parameters of machining. This study sought to examine the effect that particular machining parameters have on the quality of the surface. The investigated operation was the high-speed dry milling of a magnesium alloy with a polycrystalline diamond (PCD) cutting tool dedicated for light metal applications. Magnesium alloys have low density, and thus are commonly used in the aerospace or automotive industries. The state of the Mg surfaces was assessed using the 2D surface roughness parameters, measured on the lateral and the end face of the specimens, and the end-face 3D area roughness parameters. The description of the surfaces was complemented with the surface topography maps and the Abbott–Firestone curves of the specimens. Most 2D roughness parameters were to a limited extent affected by the changes in the cutting speed and the axial depth of cut, therefore, the results from the measurements were subjected to statistical analysis. From the data comparison, it emerged that PCD-tipped tools are resilient to changes in the cutting parameters and produce a high-quality surface finish.


2010 ◽  
Vol 447-448 ◽  
pp. 816-820 ◽  
Author(s):  
Erween Abdul Rahim ◽  
Hiroyuki Sasahara

Surface integrity is particularly important for the aerospace industry components in order to permit longer service life and maximized its reliability. This present work compares the performance of palm oil and synthetic ester on surface roughness, surface defect, microhardness and subsurface deformation when high speed drilling of Ti-6Al-4V under MQL condition. The drilling tests were conducted with AlTiN coated carbide tool. The surface roughness decreased with increasing in cutting speed and thicker subsurface deformation was formed underneath the machined surface. Grooves, cavities, pit holes, microcracks and material smearing were the dominant surface damages thus deteriorated the machined surface. For both lubricants, the machined surface experienced from thermal softening and work hardening effect thus gave a variation in microhardness values. The results indicated the substantial benefit of MQL by palm oil on surface integrity.


2013 ◽  
Vol 837 ◽  
pp. 128-134 ◽  
Author(s):  
Gheorghe Mustea ◽  
Gheorghe Brabie

The use of magnesium alloys in construction of different components of the mechanical systems (such: cars, aerospace vehicles, medical equipment etc.) is very efficient not only because it leads to reduction of the systems weight but also because it leads to reduction or elimination of the environment polluting and to reduction of the energy consumption. Generally, the main factors that influence the quality of the machined surfaces are as follows: cutting parameters, material properties, geometry of the tools, cooling liquids and lubricants, physical and mechanical properties of the subsurface layers etc. Among the above mentioned factors, cutting parameters are the factors that strongly influence the quality of the machined surfaces. The present paper analysis the results of the experimental investigation performed to determine the influence of cutting parameters (cutting speed, feed rate and cutting depth) on the surface quality machined by turning the AZ61 magnesium alloy. The main characteristics of the machined surface quality analyzed in experimental investigation were the surface roughness and hardness. The main conclusions resulted from the results analysis were as follows: the decrease of the feed rate led to surface roughness decrease and hardness increase; the increase of the cutting speed also led to an improved surface quality.


Metals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1172
Author(s):  
Abdulmajeed Dabwan ◽  
Saqib Anwar ◽  
Ali M. Al-Samhan ◽  
Mustafa M. Nasr

The machining of the electron beam melting (EBM) produced parts is a challenging task because, upon machining, different part orientations (EBM layers’ orientations) produce different surface quality even when the same machining parameters are employed. In this paper, the EBM fabricated parts are machined in three possible orientations with regard to the tool feed direction, where the three orientations are “tool movement in a layer plane” (TILP), “tool movement perpendicular to layer planes” (TLP), and “tool movement parallel to layers planes” (TPLP). The influence of the feed rate, radial depth of cut, and cutting speed is studied on surface roughness, cutting force, micro-hardness, microstructure, chip morphology, and surface morphology of Ti6Al4V, while considering the EBM part orientations. It was found that different orientations have different effects on the machined surface during milling. The results show that the EBM parts can achieve good surface quality and surface integrity when milled along the TLP orientation. For instance, surface roughness (Sa) can be improved up to 29% when the milling tool is fed along the TLP orientation compared to the other orientations (TILP and TPLP). Furthermore, surface morphology significantly improves with lower micro-pits, redeposited chips, and feed marks in case of the TLP orientation.


2016 ◽  
Vol 7 (1) ◽  
pp. 85-91
Author(s):  
Elias Rezvani ◽  
Hamid Ghayour ◽  
Masoud Kasiri

Abstract. In the present study, the effect of machining parameters and recrystallization on surface quality of Al5083 has been investigated. In order to achieve minimum surface roughness of aluminum 5083 samples, statistical test design method of "full factorial" was used. In order to achieve the phenomenon of recrystallization, aluminum 5083 samples were set under 50 % cold rolling mechanical operations. Then, the rolled samples were annealed for 2.5 to 240 min at 250 °C. The stress-strain curves were obtained from tensile tests. Then, dry machining was carried out on the original and crystallized samples under the same conditions. Results of surface roughness, tensile, and microstructure tests indicated the reduction of surface roughness in the crystallized sample.


Author(s):  
Brian Stringer ◽  
Rui Liu ◽  
Alfonso Fuentes Aznar ◽  
Patricia Iglesias

Gear milling is one of the common gear manufacturing processes. In gear milling, the cutting edge of the cutting tool has an identical profile with the profile between gear teeth, and the cutting tool travels along the axial direction of the gear blank to produce the gear tooth by tooth. Due to the high requirements about the dimensional accuracy and the surface roughness during the gear manufacturing process, it is very crucial to understand the influences of cutting conditions on those requirements to improve the quality of the product and increase the production rate. In this study, a machined gear blank made from 1018 cold-rolled steel was subjected to variable speed and feed-rates in a traditional milling operation using a standard gear-milling cutter. The effect of the variable speed and feed-rates were analyzed by measuring the total lead (helix) error, total profile (involute) error, and surface finish of each gear tooth subjected to the variable cutting conditions. The objective is to experimentally investigate the correlation between the cutting conditions, i.e. cutting speed and feed, with the accuracy and quality of the machined surface during the gear milling process.


2021 ◽  
Vol 105 (1) ◽  
pp. 381-389
Author(s):  
David Dobrocky ◽  
Josef Sedlak ◽  
Zdenek Joska ◽  
Jiri Prochazka ◽  
Zbynek Studeny ◽  
...  

The article deals with the evaluation of the influence of conventional methods of machining on the surface quality of selected technical plastics. The thermoplastic polymer polyoximethylene (POM-C) Ertacetal C and polyamide (PA 6) Ertalon 6SA were selected for machining. Both materials are suitable for machining and are used for the production of precision mechanical components (e.g. gears, plain bearings, guides, etc.), but also in electronics and electrical engineering. In all these applications, the quality of machined surfaces is important, especially for functional surfaces that interact with other surfaces. Test specimens from these materials were turned and milled. The technological conditions of machining (revolutions per minute n, cutting speed vc , feed f, depth of cut ap ) were adapted to achieve approximately the same surface roughness values. The milled samples were machined with and without cooling medium (for drought). Turning was performed only dry. As the cutting speed vc increased, the surface roughness of the turned Ertacetal C material decreased, while milling led to a deterioration in the roughness as the cutting speed vc increased. Similar behavior was observed for Ertalon 6SA. The process fluid led to a deterioration in the roughness of the milled surfaces of both plastics. Turned surfaces showed worse roughness than milled surfaces.


Minimum quantity lubrication (MQL) is an eco-friendly method, where a small amount of fluid was sprayed to cutting edge in mist form with the aid of the air. The foregoing studies revealed that inappropriate machining parameters without the assistance of the cutting fluid methods became a major challenge in milling aluminum alloy 7075-T6. The paper presents the findings of the experimental work to assess the effect of machining parameters towards cutting tool life and machined surface roughness in milling aluminum alloy 7075-T6 at high cutting speed under MQL condition. An eight-run experiment was designed according to full factorial design based upon two levels of cutting speed (500 m/min, 600 m/min), feed rate (0.12 mm/tooth, 0.15 mm/tooth), and axial depth of cut (1.40 mm, 1.70 mm) and then analyzed employed ANOVA to determine the significant machining parameters. The cutting tool life and machined surface roughness were assigned by the rejection criterion of tool flank wear in the milling operation. The optical microscope and portable surface roughness tester were applied to analyze tool wear and average surface roughness value. Cutting speed and feed rate were significantly contributing to the tool life and surface roughness. The longest tool lifespan of 20.14 minutes and lowest surface roughness value of 0.569 µm were obtained at a speed of 500 and 600 m/min, respectively, with a low combination of the rest of parameter which are 0.12 mm/tooth and 1.40 mm.


2015 ◽  
Vol 761 ◽  
pp. 293-297
Author(s):  
Raja Izamshah ◽  
A. Yu Lung ◽  
Effendi Mohamad ◽  
Mohd Asyadi Azam ◽  
Mohd Amri ◽  
...  

Polyetheretherketones (PEEK) have been widely used as biomaterials for trauma, orthopedics and spinal implants. However, machining of this material poses several challenges such as rough machined surface which can affect the implant functional application. This research attempts to optimize the machining parameter (cutting speed, feed rate and depth of cut) for effectively machining Polyetheretherketones (PEEK) implant material using carbide cutting tools. Apart from optimizing machining parameters, effects of annealing condition on PEEK towards surface qualities are discuss. Response Surface Methodology (RSM) technique was used to evaluate the effects of the parameters and their interaction towards the ability of the optimum conditions. Based on the analysis results, the optimal machining parameter to obtain the smallest surface roughness values were by using spindle speed of 5754 rpm, feed rate of 0.026 mm/tooth and 5.11 mm depth of cut for un-annealed PEEK. As for the annealed PEEK to get the smallest surface roughness values were by using spindle speed of 5865 rpm, feed rate of 0.025 mm/tooth and 2 mm depth of cut.


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