Optimization of cryogenic treatment effects on the surface roughness of cutting tools

Cryogenic treatment has been used in recent years to improve the performance of cutting tools. This study evaluated the machinability of a nickel–molybdenum-based super alloy using cryogenically treated (–80 ℃ and –145 ℃) ceramic inserts under dry turning conditions. Three cutting speeds (350, 400, and 450 m/min), three feed rates (0.1, 0.2, and 0.3 mm/rev), and a 1-mm fixed cutting depth were used in the turning tests. Experiments were conducted using the Taguchi orthogonal array L27 design. The factors affecting the surface roughness (Ra) were determined via analysis of variance. The effect of cryogenic treatment type (shallow and deep), cutting speed, and feed rate on surface roughness was investigated. Results of the analysis determined that the feed rate was the major parameter that affected surface roughness and that the deep cryogenic treatment was more effective. The regression analysis confirmed that the experimental results and the predicted values were within the 95% confidence interval. The most effective parameter affecting the surface roughness was feed rate at a contribution of 57.9%. The contribution of the cutting tool type to the surface roughness was 28.5%. The results obtained showed that the surface roughness can be optimized for turning the Hastelloy c22 super alloy with the Taguchi method.

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Investigation of Multiparameter Laser Stripping of AlTiN and DLC C Coatings

Materials ◽

10.3390/ma14040951 ◽

2021 ◽

Vol 14 (4) ◽

pp. 951

Author(s):

Tomáš Primus ◽

Josef Hlavinka ◽

Pavel Zeman ◽

Jan Brajer ◽

Martin Šorm ◽

...

Keyword(s):

Surface Roughness ◽

High Efficiency ◽

Steel Substrate ◽

Cutting Tools ◽

High Hardness ◽

Working Time ◽

Nanosecond Laser ◽

Altin Coating ◽

Successful Removal ◽

Frequency Laser

The lifetime and properties of cutting tools and forming moulds can be prolonged and enhanced by the deposition of hard, thin coatings. After a certain period of usage, the coating will deteriorate. Any remaining coating must be removed prior to successful recoating. Laser stripping is a fast and environmentally friendly coating removal method. In this paper, we present laser removal of two types of coatings deposited on a 1.2379 tool steel substrate, namely, an AlTiN coating with high hardness and a DLC C coating with a small coefficient of friction (COF). A powerful nanosecond laser was employed to remove the coating from the substrate with high efficiency, along with suitable residual surface roughness. Measurements were taken of surface roughness, removed depth, and working time on a stripped area of 1 cm2. The samples were evaluated under a microscope, with a 3D profilometer, and by EDS chemical analysis. Successful removal of the coating was confirmed by optical analysis, but detailed chemical characterisation showed that about 30% of the coating element may remain on the surface. Moreover, a working time of less than 7.5 s per cm2 was obtained in this study. In addition, it was shown that the application of a second low energy, high frequency laser beam pass leads to remelting of the peaks of the material and reduced surface roughness.

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Influence of cryogenic treatment of cutting tool inserts on tool wear and surface roughness during milling of Inconel 718

10.1063/5.0022831 ◽

2020 ◽

Author(s):

Ivan Sunit Rout ◽

P. Pal Pandian ◽

Manish Mathew ◽

Kevin Lobo Ivan ◽

Shomyajit Misra

Keyword(s):

Surface Roughness ◽

Tool Wear ◽

Inconel 718 ◽

Cutting Tool ◽

Cryogenic Treatment

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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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Effects of deep cryogenic treatment on machinability, hardness and microstructure in dry turning process of tempered steels

Proceedings of the Institution of Mechanical Engineers Part E Journal of Process Mechanical Engineering ◽

10.1177/0954408920979446 ◽

2020 ◽

pp. 095440892097944

Author(s):

Menderes Kam

Keyword(s):

Cryogenic Treatment ◽

Cutting Tools ◽

Cutting Speed ◽

Point Of View ◽

Turning Process ◽

Deep Cryogenic Treatment ◽

Dry Turning ◽

Control Factors ◽

Heat Treated ◽

Hardness Values

This study investigated the effects of Deep Cryogenic Treatment (DCT) on machinability, hardness, and microstructure in dry turning process of AISI 4140 (48-51 HRc) tempered steels with ceramic cutting tools on the surface roughness (Ra). DCT process of steels has shown significant improvement in their mechanical properties. In this context, experiments were made with Taguchi L16 method and optimum values were determined. Three different values for each control factors as: different heat treated samples, cutting speeds (160, 200, 240, 280 m/min), feed rates (0.08, 0.12, 0.16, 0.20 mm/rev) were selected. As a result, the lowest Ra value was found to be 0.159 µm for the DCTT36 sample at a cutting speed of 240 m/min, a feed rate of 0.08 mm/rev. The optimum Ra value was the lowest for the DCTT36 sample compared to the other samples as 0.206 µm. The hardness values of the micro and macro were highest for the DCTT36 sample. Microstructural point of view Scanning Electron Microscopy (SEM) point of view, the DCCT36 sample showed that best results owing to its homogeneity. It was concluded that lower Ra values can be obtained with ceramic cutting tool in dry turning experiments according to the studies in the literature review. It is thought to be preferred as an alternative to cylindrical grinding process due to lower cost.

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Remaining Useful Life Prediction of Cutting Tools Using an Inverse Gaussian Process Model

Applied Sciences ◽

10.3390/app11115011 ◽

2021 ◽

Vol 11 (11) ◽

pp. 5011

Author(s):

Yuanxing Huang ◽

Zhiyuan Lu ◽

Wei Dai ◽

Weifang Zhang ◽

Bin Wang

Keyword(s):

Surface Roughness ◽

Failure Criterion ◽

Cutting Tool ◽

Cutting Tools ◽

Remaining Useful Life ◽

Model Parameters ◽

Inverse Gaussian ◽

Wear Process ◽

Useful Life ◽

Dynamic Wear

In manufacturing, cutting tools gradually wear out during the cutting process and decrease in cutting precision. A cutting tool has to be replaced if its degradation exceeds a certain threshold, which is determined by the required cutting precision. To effectively schedule production and maintenance actions, it is vital to model the wear process of cutting tools and predict their remaining useful life (RUL). However, it is difficult to determine the RUL of cutting tools with cutting precision as a failure criterion, as cutting precision is not directly measurable. This paper proposed a RUL prediction method for a cutting tool, developed based on a degradation model, with the roughness of the cutting surface as a failure criterion. The surface roughness was linked to the wearing process of a cutting tool through a random threshold, and accounts for the impact of the dynamic working environment and variable materials of working pieces. The wear process is modeled using a random-effects inverse Gaussian (IG) process. The degradation rate is assumed to be unit-specific, considering the dynamic wear mechanism and a heterogeneous population. To adaptively update the model parameters for online RUL prediction, an expectation–maximization (EM) algorithm has been developed. The proposed method is illustrated using an example study. The experiments were performed on specimens of 7109 aluminum alloy by milling in the normalized state. The results reveal that the proposed method effectively evaluates the RUL of cutting tools according to the specified surface roughness, therefore improving cutting quality and efficiency.

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Investigation on the Surface Quality Obtained during Trochoidal Milling of 6082 Aluminum Alloy

Machines ◽

10.3390/machines9040075 ◽

2021 ◽

Vol 9 (4) ◽

pp. 75

Author(s):

Nikolaos E. Karkalos ◽

Panagiotis Karmiris-Obratański ◽

Szymon Kurpiel ◽

Krzysztof Zagórski ◽

Angelos P. Markopoulos

Keyword(s):

Surface Roughness ◽

Surface Quality ◽

Process Parameters ◽

Manufacturing Industry ◽

High Surface ◽

Cutting Tools ◽

Cutting Speed ◽

Depth Of Cut ◽

High Surface Quality ◽

Trochoidal Milling

Surface quality has always been an important goal in the manufacturing industry, as it is not only related to the achievement of appropriate geometrical tolerances but also plays an important role in the tribological behavior of the surface as well as its resistance to fatigue and corrosion. Usually, in order to achieve sufficiently high surface quality, process parameters, such as cutting speed and feed, are regulated or special types of cutting tools are used. In the present work, an alternative strategy for slot milling is adopted, namely, trochoidal milling, which employs a more complex trajectory for the cutting tool. Two series of experiments were initially conducted with traditional and trochoidal milling under various feed and cutting speed values in order to evaluate the capabilities of trochoidal milling. The findings showed a clear difference between the two milling strategies, and it was shown that the trochoidal milling strategy is able to provide superior surface quality when the appropriate process parameters are also chosen. Finally, the effect of the depth of cut, coolant and trochoidal stepover on surface roughness during trochoidal milling was also investigated, and it was found that lower depths of cut, the use of coolant and low values of trochoidal stepover can lead to a considerable decrease in surface roughness.

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Characteristic properties of AlTiN and TiN coated HSS materials

Industrial Lubrication and Tribology ◽

10.1108/ilt-10-2012-0097 ◽

2015 ◽

Vol 67 (2) ◽

pp. 172-180 ◽

Cited By ~ 3

Author(s):

Mumin Sahin ◽

Cenk Misirli ◽

Dervis Özkan

Keyword(s):

Surface Roughness ◽

Tensile Strength ◽

High Speed ◽

Cutting Tools ◽

High Speed Steel ◽

Wear Properties ◽

Content Type ◽

X Ray ◽

Number Of Cycles ◽

Future Work

Purpose – The purpose of this paper is to examine mechanical and metallurgical properties of AlTiN- and TiN-coates high-speed steel (HSS) materials in detail. Design/methodology/approach – In this study, HSS steel parts have been processed through machining and have been coated with AlTiN and TiN on physical vapour deposition workbench at approximately 6,500°C for 4 hours. Tensile strength, fatigue strength, hardness tests for AlTiN- and TiN-coated HSS samples have been performed; moreover, energy dispersive X-ray spectroscopy and X-ray diffraction analysis and microstructure analysis have been made by scanning electron microscopy. The obtained results have been compared with uncoated HSS components. Findings – It was found that tensile strength of TiAlN- and TiN-coated HSS parts is higher than that of uncoated HSS parts. Highest tensile strength has been obtained from TiN-coated HSS parts. Number of cycles for failure of TiAlN- and TiN-coated HSS parts is higher than that for HSS parts. Particularly TiN-coated HSS parts have the most valuable fatigue results. However, surface roughness of fatigue samples may cause notch effect. For this reason, surface roughness of coated HSS parts is compared with that of uncoated ones. While the average surface roughness (Ra) of the uncoated samples was in the range of 0.40 μm, that of the AlTiN- and TiN-coated samples was in the range of 0.60 and 0.80 μm, respectively. Research limitations/implications – It would be interesting to search different coatings for cutting tools. It could be the good idea for future work to concentrate on wear properties of tool materials. Practical implications – The detailed mechanical and metallurgical results can be used to assess the AlTiN and TiN coating applications in HSS materials. Originality/value – This paper provides information on mechanical and metallurgical behaviour of AlTiN- and TiN-coated HSS materials and offers practical help for researchers and scientists working in the coating area.

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Analysis of tool vibration and surface roughness during turning process of tempered steel samples using Taguchi method

Proceedings of the Institution of Mechanical Engineers Part E Journal of Process Mechanical Engineering ◽

10.1177/09544089211001976 ◽

2021 ◽

pp. 095440892110019

Author(s):

Menderes Kam ◽

Mustafa Demirtaş

Keyword(s):

Surface Roughness ◽

Taguchi Method ◽

Cutting Tools ◽

Cutting Speed ◽

Machining Parameters ◽

Turning Process ◽

Machining Time ◽

Tool Vibration ◽

Control Factors ◽

Tempered Steel

This study analyzed the tool vibration (Vib) and surface roughness (Ra) during turning of AISI 4340 (34CrNiMo6) tempered steel samples using Taguchi Method. In this context, Taguchi design L18 (21 × 32) was used to analyze the experimental results. The vibration amplitude values from cutting tools were recorded for different machining parameters, control factors; two different sample hardness (46 and 53 HRc), three different cutting speeds (180, 220, 260 m.min−1), and feed rates (0.08, 0.14, 0.20 mm.rev−1) were selected. The machining parameters giving optimum Vib and Ra values were determined. Regression analysis is applied to predict values of Vib and Ra. Analysis of variance was used to determine the effects of machining parameters on the Vib and Ra values. The most important machining parameters were found to be the feed rate, sample hardness, and cutting speed for Vib and Ra, respectively. The lowest Vib and Ra values were obtained in 46 HRc sample as 0.0022 gRMS and 0.255 µm, respectively. The surface quality can be improved by reducing the sources of vibration by using appropriate machining parameters. As a result, there is a significant relationship between Ra and Vib. The lower Ra values were found during turning process of tempered steel samples according to the literature studies. It is suggested that the process can be preferred as an alternative process to grinding process due to lower cost and machining time. In application of the turning of experiment samples by ceramic cutting tool, a substantial technological and economical benefit has been observed.

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Performance characteristics of steel 1.2842 after nitridation

Science & Military ◽

10.52651/sam.a.2021.1.43-48 ◽

2021 ◽

Vol 16 (1) ◽

pp. 43-48

Author(s):

Michal Krbaťa ◽

◽

Jana Escherová ◽

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Wear Resistance ◽

Chemical Composition ◽

Plasma Nitriding ◽

Cutting Tools ◽

Operating Costs ◽

Mechanical And Tribological Properties ◽

Structure Thickness ◽

Pin On Disc

The paper deals with the change in mechanical properties and wear of 1.2842 universal tool steel after plasma nitriding, which is widely used to produce cutting tools with good durability and low operating costs. Plasma nitriding was performed at a temperature of 500 °C for 10-hour period in a standard N2 /H2 atmosphere with 1:3 gases ratio. Microstructure, phase structure, thickness of a nitriding layer and surface roughness of samples were measured with optical microscopes and a profilometer. Verification of a chemical composition was carried out on the BAS TASMAN Q4 device. Wear resistance was measured on a universal TRIBOLAB UTM 3 tribometer, through a, “pin on disc“ method. The results of experiments have shown that plasma nitriding process, significantly improves the mechanical and tribological properties of selected materials.

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