Surveying the topography and examining the quality of the machined surface of selected hardened steels in the milling process

The article deals with the surface roughness examination of three selected hard materials, that is, K100, 100CrMnMo7, and 16MnCr5, all with a defined hardness of HRC 60. The individual materials were machined using sintered carbide and cermet cutting materials with TiCN and TiN + TiCN + Al2O3 coatings. The research resided in the realization of three experiments. These experiments were carried out by three alternatives differing in the setting of basic cutting parameters. The experimental procedure was realized by the simulation method and direct contact measurement method of surface roughness. From the overall technical evaluation described in the practical part of the article, for the primarily observed parameter, the surface roughness, the least suitable values were obtained in the evaluation of the material from experiment No. 1-K100 with hardness HRC60. The experiments realized and the results achieved show that the machining of tool steels and other superhard materials requires special cutting tools, machines, and the use of progressive technologies, to ensure the production of a dimensionally and qualitatively shaped functional component.

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The Effect of the Cutting Parameters on the Machined Surface Roughness

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.260.219 ◽

2017 ◽

Vol 260 ◽

pp. 219-226 ◽

Cited By ~ 1

Author(s):

Viktors Gutakovskis ◽

Eriks Gerins ◽

Janis Rudzitis ◽

Artis Kromanis

Keyword(s):

Surface Roughness ◽

Metal Cutting ◽

Cutting Tool ◽

Cutting Tools ◽

Cutting Parameters ◽

Cutting Process ◽

Tool Geometry ◽

Machining Parameters ◽

Machined Surface ◽

Machined Surface Roughness

From the invention of turning machine or lathe, some engineers are trying to increase the turning productivity. The increase of productivity is following after the breakout in instrumental area, such as the hard alloy instrument and resistance to wear cutting surfaces. The potential of cutting speed has a certain limit. New steel marks and cutting surfaces types allow significantly increase cutting and turning speeds. For the most operation types the productivity increase begins from the feeding increase. But the increase of feeding goes together with machined surface result decreasement. Metal cutting with high feeding is one of the most actual problems in the increasing of manufacturing volume but there are some problems one of them is the cutting forces increasement and larger metal removal rate, which decrease the cutting tool life significantly. Increasing of manufacturing volume, going together with the cutting instrument technology and material evolution, such as the invention of the carbide cutting materials and wear resistant coatings such as TiC and Ti(C,N). Each of these coating have its own properties and functions in the metal cutting process. Together with this evolution the cutting tool geometry and machining parameters dependencies are researched. Traditionally for the decreasing the machining time of one part, the cutting parameters were increased, decreasing by this way the machining operation quantity. In our days the wear resistance of the cutting tools increasing and it is mostly used one or two machining operations (medium and fine finishing). The purpose of the topic is to represent the experimental results of the stainless steel turning process, using increased cutting speeds and feeding values, to develop advanced processing technology, using new modern coated cutting tools by CVD and PVD methods. After investigation of the machined surface roughness results, develop the mathematical model of the cutting process using higher values of the cutting parameters.

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Optimization of the Process Parameters in Milling of Aluminum Alloys

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.896.293 ◽

2020 ◽

Vol 896 ◽

pp. 293-298

Author(s):

Nicolae Craciunoiu ◽

Emil Nicusor Patru ◽

Adrian Sorin Rosca ◽

Dumitru Panduru ◽

Marin Bica

Keyword(s):

Aluminum Alloys ◽

Tool Wear ◽

Cutting Temperature ◽

Cutting Parameters ◽

Milling Process ◽

Depth Of Cut ◽

Machined Surface ◽

Experimental Conditions ◽

Milling Parameters

In order to control the temperature during milling process of aluminum alloys and keeping as minimum as possible, the choice of the cutting parameters and their optimization is very important, both for the tool wear but also for the surface quality of machined surface. The main purpose of this paper is to find the optimum values of the milling parameters (rotational speed and depth of cut) so that the minimum value for the temperature to be obtained. Using adequate experimental conditions with contact measurements techniques (thermocouple K-type) carried out on the some types of aluminum alloys and the appropriate statistical instruments, the most influencing cutting parameters and their values on the cutting temperature can be found. The results are presented both analytical and graphical.

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Spectral Properties of Milling and Machined Surface

Materials Science Forum ◽

10.4028/www.scientific.net/msf.836-837.570 ◽

2016 ◽

Vol 836-837 ◽

pp. 570-577 ◽

Cited By ~ 3

Author(s):

Gabor Stepan ◽

Mate Toth ◽

Daniel Bachrathy ◽

Suri Ganeriwala

Keyword(s):

Surface Quality ◽

Spectral Properties ◽

Cutting Tools ◽

Milling Process ◽

Machined Surface ◽

Industrial Case Study ◽

Machined Surface Quality ◽

Negative Effect

Machine tool vibrations cause uncomfortable noise, may damage the edges of cutting tools or certain parts of machine tools, but most importantly, they always have negative effect on the quality of the machined surface of workpieces. These vibrations are especially intricate in case of milling processes where complex tool geometries are used, like helical, serrated, non-uniform pitch angles, and so on. During the milling process, the arising vibrations include free, forced, self-excited, and even parametrically forced vibrations together with their different combinations. Regarding surface quality, the most harmful is the self-excited one called chatter, which is related to the regenerative effect of the cutting process. Its relation to machined surface quality is demonstrated in an industrial case study. The modelling and the corresponding cutting stability are presented in case of a helical tool applied for milling with large axial immersions. The extremely rich spectrum of the measured vibration signals are analyzed by means of model-based predictions, and the results are compared with the spectral properties of the corresponding machined surfaces. The conclusions open the way for new kinds of chatter identification.

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Study on the Machined Surface Geometry Generated by Multi-Axis Ball End Milling Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.770.370 ◽

2013 ◽

Vol 770 ◽

pp. 370-375

Author(s):

Xiao Xiao Chen ◽

Jun Zhao ◽

Yong Wang Dong ◽

Shuai Liu ◽

Jia Bang Zhao

Keyword(s):

Surface Roughness ◽

End Milling ◽

Cutting Parameters ◽

Peak Height ◽

Milling Process ◽

Depth Of Cut ◽

Small Range ◽

Surface Geometry ◽

Machined Surface ◽

Two Parameters

This paper investigated the surface generated by single factor experiment under multi-axis finish milling condition, and the effects of cutting parameters on surface textures, 2D and 3D surface topographies and surface roughness characteristics were analyzed. Surface features evaluation indicators of Ra, Rq, Rt, surface heights histogram, maximum valley depth and maximum peak height corresponding to various cutting parameters were presented and discussed. The machining marks are closely related with tool orientation angles. The orderly distributions of concave and convex patterns on the machined surface are produced by the special cutting orientation of the cutting edges. The feed per tooth, spindle speed, tilt angle, and lead angle apparently affect surface roughness, while depth of cut and radial width of cut have no obvious effects on the surface roughness when the two parameters values vary in a small range.

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Investigation of Surface Quality for Minor Scale Diameter of Biodegradable Magnesium Alloys during the Turning Process Using a Different Tool Nose Radius

Metals ◽

10.3390/met11081174 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1174

Author(s):

Sophal Hai ◽

Hwa-Chul Jung ◽

Won-Hyun Shim ◽

Hyung-Gon Shin

Keyword(s):

Surface Roughness ◽

Surface Quality ◽

Feed Rate ◽

Cutting Parameters ◽

Spindle Speed ◽

Turning Process ◽

Nose Radius ◽

Machined Surface ◽

Tool Nose Radius

The main objective of the study is to analyze the various cutting parameters to investigate the surface quality of the minor scale diameter of magnesium alloy in the dry turning process using a different tool nose radius (r). The surface roughness (Ra) was gauged, and micro-images produced by scanning electron microscopy (SEM) were reviewed to evaluate the machined surface topography. The analysis of variance (ANOVA), linear regression model and signal-to-noise (S/N) ratio were applied to investigate and optimize the experimental conditions for surface roughness. The study results imply that the feed rate and tool nose radius significantly affected the surface quality, but the spindle speed did not. The linear regression model is valid to forecast the surface roughness. The cutting parameters for optimum surface quality are a combination of a spindle speed of 710 rpm, a feed rate of 0.052 mm/rev and a tool nose radius of 1.2 mm. The machined surface topography contains the feed marks, micro-voids, material side and material debris, but they become smaller and decrease at a lower feed rate, larger tool nose radius and higher spindle speed. These results show the good surface quality of magnesium alloys in a dry turning process, which could be applied in implant, orthopedic and trauma surgery.

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Vibration Analysis Based on AR Trispectrum in Milling Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.97-101.1895 ◽

2010 ◽

Vol 97-101 ◽

pp. 1895-1901

Author(s):

Yu Yan Jiang ◽

Yi Jian Huang ◽

Xiu Cheng Ye

Keyword(s):

Surface Quality ◽

Vibration Analysis ◽

Metal Cutting ◽

Cutting Parameters ◽

Milling Process ◽

Cutting Fluid ◽

Depth Of Cut ◽

Machined Surface ◽

Machined Surface Quality

This paper presents the use of vibration analysis based on autoregressive (AR) trispectrum in milling process to indicate the relationship between machined surface quality of workpiece and spectrum character under a variety of different cutting parameter settings, such as the depth of cut, the feed rate and the spindle speed. The metal cutting experiments were performed on steel A3 material without using any cutting fluid. The experimental results for slices analysis of trispectra indicated that the spectral peaks were abundant as the milling process went smoothly. The roughness value measured reflects the machined surface quality of workpice. According to the changes for spectral peak and roughness value, a conclusion was made that the proposed trispectrum slices method for choosing cutting parameters and monitoring the machined surface quality in milling process was practicable.

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Comparison of Surface Roughness When Turning and Milling

Periodica Polytechnica Mechanical Engineering ◽

10.3311/ppme.17898 ◽

2021 ◽

Author(s):

Abdulwahab Mgherony ◽

Balázs Mikó ◽

Gabriella Farkas

Keyword(s):

Surface Roughness ◽

Geometric Model ◽

Cutting Parameters ◽

Machining Process ◽

Depth Of Cut ◽

Real Surface ◽

Machined Surface ◽

Longitudinal Turning ◽

Machining Process Planning

The quality of a machined surface can be described by macro and micro parameters, like the size error, the form and position error or the surface roughness. The task of machining process planning is to find the best machining method and parameters, which ensure the required quality. In this article, the surface roughness in the case of turning and milling technologies is analysed. The effect of the cutting parameters (feed at turning and depth of cut at milling) and the tool parameter (corner radius) are investigated. The results are compared with the theoretical geometric model of surface roughness. In longitudinal turning as well as in constant Z-level milling, the geometric model of surface roughness is similar. The article presents whether the real surface roughness is similar too.

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Evaluation of Cutting-Tool Coating on the Surface Roughness and Hole Dimensional Tolerances during Drilling of Al6061-T651 Alloy

Materials ◽

10.3390/ma14071783 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1783

Author(s):

Hamza A. Al-Tameemi ◽

Thamir Al-Dulaimi ◽

Michael Oluwatobiloba Awe ◽

Shubham Sharma ◽

Danil Yurievich Pimenov ◽

...

Keyword(s):

Surface Roughness ◽

Cutting Tool ◽

Good Practice ◽

Cutting Tools ◽

Statistical Design ◽

Cutting Parameters ◽

Statistical Design Of Experiments ◽

Hole Quality ◽

Coated Tools ◽

Tool Coating

Aluminum alloys are soft and have low melting temperatures; therefore, machining them often results in cut material fusing to the cutting tool due to heat and friction, and thus lowering the hole quality. A good practice is to use coated cutting tools to overcome such issues and maintain good hole quality. Therefore, the current study investigates the effect of cutting parameters (spindle speed and feed rate) and three types of cutting-tool coating (TiN/TiAlN, TiAlN, and TiN) on the surface finish, form, and dimensional tolerances of holes drilled in Al6061-T651 alloy. The study employed statistical design of experiments and ANOVA (analysis of variance) to evaluate the contribution of each of the input parameters on the measured hole-quality outputs (surface-roughness metrics Ra and Rz, hole size, circularity, perpendicularity, and cylindricity). The highest surface roughness occurred when using TiN-coated tools. All holes in this study were oversized regardless of the tool coating or cutting parameters used. TiN tools, which have a lower coating hardness, gave lower hole circularity at the entry and higher cylindricity, while TiN/TiAlN and TiAlN seemed to be more effective in reducing hole particularity when drilling at higher spindle speeds. Finally, optical microscopes revealed that a built-up edge and adhesions were most likely to form on TiN-coated tools due to TiN’s chemical affinity and low oxidation temperature compared to the TiN/TiAlN and TiAlN coatings.

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Experimental Investigation on Surface Roughness in Precision Cutting Ti6Al4V Alloy Using Diamond Tools

Materials Science Forum ◽

10.4028/www.scientific.net/msf.800-801.576 ◽

2014 ◽

Vol 800-801 ◽

pp. 576-579

Author(s):

Lin Hua Hu ◽

Ming Zhou ◽

Yu Liang Zhang

Keyword(s):

Surface Roughness ◽

Cutting Speed ◽

Polycrystalline Diamond ◽

Cutting Parameters ◽

Limited Range ◽

Nose Radius ◽

Machined Surface ◽

Machined Surface Roughness ◽

Titanium Alloy Ti6al4v ◽

Pcd Tools

In this work, cutting experiments were carried out on titanium alloy Ti6Al4V by using polycrystalline diamond (PCD) tools to investigate the effects of the tool geometries and cutting parameters on machined surface roughness. Experimental results show machined surface roughness decreases with increases in the flank angle, tool nose radius and cutting speed within a limited range respectively, and begins to increase as the factors reaches to certain values respectively. And machined surface roughness decreases with increases in feed rate and cutting depth respectively.

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Experimental investigation of the influence of cutting parameters on surface quality and on the special characteristics of micro-milled surfaces of hardened steels

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/09544062211013064 ◽

2021 ◽

pp. 095440622110130

Author(s):

Barnabás Zoltán Balázs ◽

Márton Takács

Keyword(s):

Surface Quality ◽

Surface Profile ◽

Cutting Parameters ◽

Relevant Information ◽

Milling Process ◽

Micro Milling ◽

Machined Surface ◽

Analysis Of Dynamics ◽

Five Axis ◽

Coated Carbide

Micro-milling is one of the most essential technologies to produce micro components, but due to the size effect, it has many special characteristics and challenges. The process can be characterised by strong vibrations, relatively large run-out and tool deformation, which directly affects the quality of the machined surface. This paper deals with a detailed investigation of the influence of cutting parameters on surface roughness and on the special characteristics of micro-milled surfaces. Several systematic series of experiments were carried out and analysed in detail. A five-axis micromachining centre and a two fluted, coated carbide micro-milling tool with a diameter of 500 µm were used for the tests. The experiments were conducted on AISI H13 hot-work tool steel and Böhler M303 martensitic corrosion resistance steel with a hardness of 50 HRC in order to gain relevant information of machining characteristics of potential materials of micro-injection moulding tools. The effect of the cutting parameters on the surface quality and on the ratio of Rz/ Ra was investigated in a comprehensive cutting parameter range. ANOVA was used for the statistical evaluation. A novel method is presented, which allows a detailed analysis of the surface profile and repetitions, and identify the frequencies that create the characteristic profile of the surface. The procedure establishes a connection between the frequencies obtained during the analysis of dynamics (forces, vibrations) of the micro-milling process and the characterising repetitions and frequencies of the surface.

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