Cutting Surface Roughness Research Articles

AISI D2 steel machining and manufacturing process optimization for tooling applications in biomedical industry

Tool steels such as AISI D2 are famous in the manufacturing industry because of their engineering applications. The precise interplay of improved hardness and toughness makes the machining of complex geometries challenging through conventional machining options. Therefore, non-conventional processes such as wire electric discharge machining (WEDM) are preferred because of their simultaneous machining and surface modification actions. To investigate the complex process parameters and their sensitivity, material removal rate (MRR) and cutting surface roughness (SR) are the corresponding performance measure characteristics for WEDM machining on AISI D2 tool steel. The L18 mixed-level Taguchi technique has been used for obtaining combinations of experiments on two levels of thickness and three levels of other remaining factors (21 × 33). Analysis of variance (ANOVA) and signal-to-noise ratio have been applied to measure the magnitude of effects on each control factor, to investigate the optimum levels of input process parameters on machining characteristics, and to identify their significance. ANOVA analysis revealed that, for both responses, all main effect variables are highly significant, with p-values equal to zero. Moreover, the coefficient of determination (R2) value in the ANOVA findings for both responses is above 97%, indicating the high reliability of the model. In addition, the composite desirability (dG) is considered to maximize MRR and minimize the SR during WEDM of D2; the better combination of optimum levels of machining parameters (T = 25.4 mm, Pon = 4 µs, SV = 95 V, and WT = 5 kg-f) has a dG of 0.5614.

Cutting surface roughness prediction model for cutting carbon steel using premixed abrasive water jet

Cutting surface roughness prediction model for cutting carbon steel using premixed abrasive water jet

High cycle fatigue life estimation of punched and trimmed specimens considering residual stresses and surface roughness

Shear cutting processes have a detrimental effect on fatigue of high strength metal components. The effect tends to increase with material grade, counteracting the task of reducing weight in chassis components using higher strength materials. Base material fatigue data are often available, but assessment of components with cut edges often require additional costly and time-consuming testing. This paper provides a methodology for estimation of fatigue life reduction by using residual stresses obtained from process simulations, and measured surface roughness in the cut edge. A stress relaxation criterion is applied to handle reduction of the initial local residual stresses. Two complex phase steels and one aluminum alloy are studied for validating the approach. Polished fatigue data is reduced to estimate S–N curves of trimmed and punched specimens at different load ratios. Good agreement between the model and test results are found for all cases. The needed data for the predictions are only a high cycle S–N relationship for polished material, uniaxial tensile properties, and the cut edge fracture surface residual stress and roughness without any parameter fitting, making it a convenient tool for estimating the reduction in fatigue life and for parameter studies.

Nanosecond-laser cutting of (TiZrHfNbTa)C high-entropy ceramics

(TiZrHfNbTa)C high-entropy ceramics have wide range of application prospects due to their excellent performance, but their hardness and brittleness make them difficult to process. In this study, novel method based on nanosecond laser was used to cut (TiZrHfNbTa)C high-entropy ceramics. Results show that laser machining is efficient strategy for high-precision machining of (TiZrHfNbTa)C high-entropy ceramics. Slit width obtained via nanosecond-laser cutting is only 26.4 % of that obtained via mechanical cutting, and average roughness and maximum height difference of cut surface are 2.078 and 20.497 μm, respectively, which are smaller than those obtained through mechanical cutting (4.296 and 29.706 μm, respectively). Furthermore, removal mechanism under the action of nanosecond laser was investigated, and it was found that cut surface of (TiZrHfNbTa)C high-entropy ceramics formed thin oxide recast layer together with carbide underneath. This study provides important results for precision machining of (TiZrHfNbTa)C high-entropy ceramics.

The Influence of the Wavelength of Laser Light on the Non-Contact Measurement of the Roughness of Shiny Cut Surfaces on Stainless Steel A304 Material

The Influence of the Wavelength of Laser Light on the Non-Contact Measurement of the Roughness of Shiny Cut Surfaces on Stainless Steel A304 Material

Generation mechanism of the surface morphology on tilted ultrasonic elliptical vibration cutting TC4 titanium alloy

TC4 titanium alloy is utilized in aerospace and a wide range of other applications due to its high strength and corrosion resistance, but its poor thermal conductivity and high ductility introduce challenges in machining. In this paper, firstly, a mathematical model of workpiece surface morphology under tilted ultrasonic elliptical vibration cutting (TUEVC) was established based on the tip trajectory and material removal mechanism, and the variation of workpiece surface morphology was investigated at different tool tilt angles θ, and it was found that the tilt θ in a certain range could significantly reduce the surface residual height compared with that of ordinary ultrasonic elliptical vibration cutting (UEVC). Second, the TUEVC experiment of TC4 titanium alloy was carried out to comparatively analyze the changes in the surface morphology, surface profile, and surface roughness of the workpiece under different tilt θ, the effect of each machining parameter (cutting speed, feed, and ultrasonic amplitude) on surface roughness was explored. The experimental results indicate that as the tilt θ changes from 0° to 90° throughout the process, the workpiece surface morphology flatness decreases and then increases. When the tilt angle θ is 45°, workpiece cutting surface roughness is minimized (Sa = 0.157), compared with the ordinary ultrasonic elliptical vibration cutting roughness is reduced by 47.6 % maximum. Both the surface morphology flatness and the surface roughness of the workpiece are at their smallest, whereas the theoretical profile curve and cutting surface profile curve are at their most consistent. Under the same machining parameters, TUEVC can reduce the surface roughness more effectively compared with UEVC, this technique reduces surface roughness by 16 %, 23 %, and 26 % at maximum for different cutting speeds, feeds, and ultrasonic amplitudes, respectively.

Immersion laser separation: Enhancing efficiency and quality in cutting irregular lenses

Irregular lenses are commonly employed in various beam shaping, imaging, and other optical applications. They require secondary processing to meet specific design and assembly criteria. Bessel beam lasers have gained popularity for their ability to efficiently separate hard-brittle materials owing to their high processing quality and speed. However, the complex surface of irregular lenses creates challenges such as refraction and scattering, which impede the laser beam’s ability to form a laser center lobe inside the material. This paper proposes an innovative technique called immersion laser separation (ILS), where an irregular lens is immersed in a refractive index matching medium to create a compound with a uniform refractive index. This approach mitigates the impact of surface complexity on the optical path of the Bessel beam. The separation of a fast axis collimator (FAC) by ILS is used as an example to test the proposed technique. The distribution characteristics of the Bessel beam light field inside the lens material under different refractive index were investigated to find that the laser consistently forms a laser center lobe inside the material during cutting when the matching deviation is small. This results in a modified area that covers the entire surface. The maximum cutting speed can reach 50 mm/s, the cutting surface roughness is less than 700 nm, and the technique produces no chips or micro-cracks, ensuring uniformly high-quality separation. Experimental and simulation results are in close agreement, suggesting that the proposed technique is effective for the efficient, high-quality cutting of irregular lenses.

Investigation of The Effect of Radial Width and Axial Depth Parameters on Surface Quality in Milling of White Marbles

In this study, surface quality and tangential cutting force and radial width (ae) and axial deep (ap) 
 parameters were investigated in the processing of white marble, which is a natural building material. 
 Five different white marbles were used in the experiments and the taguchi method was applied as the 
 test method. Depending on the number and level of parameters, the L9 orthogonal array was chosen. 
 Cutting forces and surface roughness data were collected for each marble. The optimal level and 
 contribution percentage of each parameter was determined by applying the analysis of variance with 
 the signal-to-noise (S/N) ratio. The Fr and Ra factors for all marbles were found to be ae:1 mm and ap:1 
 mm. Depending on the significance level, axial depth of cut (ap) was the primary effective parameter 
 (65-86% for Fr; 42-78% for Ra), while radial depth of cut was the secondary effective parameter (3-24% 
 for Fr; 16-35% for Ra). It can be said that the feed rate parameter was not an effective parameter in 
 general.As a result of regression analysis, a significant relationship of 83% was observed between Ra 
 surface roughness value and mineral grain size. Grain size has been the mineralogical-petrographic 
 feature affecting the surface quality of marbles.

Penggunaan Metode Preference Selection Index (PSI) Untuk Penentuan Kondisi Laser Cutting

This study discusses the application of the Preference Selection Index (PSI) method or Preference Selection Index to be able to optimize laser cutting. The application of the PSI method represents the decision making of a multi-criteria MCDM that has not been studied more and requires a consideration in determining laser cutting parameters. The main purpose of applying this method is for multi-criterion decision making (MCDM) that does not require an assessment of the relative significance of the criteria under consideration. The method used is the preference selection index, which can provide convenience in making decisions because the process is very simple. The results of experiments using the L27 Taguchi orthogonal array, Cut surface roughness, heat-affected zone (HAZ), kerf width and material removal rate (MRR) were considered optimization criteria. The methodology is found to be particularly useful in real manufacturing environments as it involves simple calculations that are easy to understand and apply.

Optimization of Abrasive Waterjet Cutting by Using the CODAS Method with Regard to Interdependent Processing Parameters

The paper shows performance optimization effects of steel machining by abrasive water jet (AWJ). An innovative combinative distance-based assessment method (CODAS) is implemented for the optimization of cutting parameters like pump pressure, feed rate, and abrasive flow rate over cutting depth, and cut kerf surface roughness. The CODAS algorithm is among those based on measuring the distance between a scenario (in this case processing parameters in terms of performance and quality indicators) - and a certain benchmark. A benchmark is a specific hypothetical set of processing parameters devised or determined from available data. To determine the best set of process control parameters, a CODAS approach was performed with some weighting determinations. To set the initial parameters of the weights, it was proposed to calculate based on entropy weight method (EWM), that measures output value dispersion in cutting process. This technique simplifies multiple compound responses by preserving a single response.

Effects of Machining Parameters of C45 Steel Applying Vegetable Lubricant with Minimum Quantity Cooling Lubrication (MQCL)

One of the most significant performance indicators for measuring the machinability of materials is tool wear and surface roughness. Choosing the best combination of cutting parameters can help reduce production costs, which is what the manufacturing industry is interested in. At the same time, industries are always looking for an alternative to conventional flood cooling since its use creates an environmental burden and health concerns for the operators. Therefore, vegetable oil-based minimum quantity cooling lubrication (MQCL) is considered a cutting environment. Sunflower oil is utilized as base fluid in MQCL and applied to the cutting zone through a nozzle. The turning experiments are conducted on C45 material which is widely used in various industrial applications, including numerous automotive components. Since flood cooling is widely utilized in machining C45, it is the present-day need to assess alternative cooling and lubricating approaches to avoid the adverse effects of flood cooling. The Taguchi method was used in the present work to minimize surface roughness and tool wear. L9 orthogonal array was constructed, and experiments were performed on C45 steel using coated carbide cutting tools. The statistical approach is utilized to evaluate the effect of cutting parameters on output responses. The optimal cutting settings for cutting speed, feed, and depth of cut to minimize surface roughness are 100 m/min, 0.18 mm/rev, 0.150 mm, and 80 m/min, 0.18 mm/rev, and 0.150 mm for tool wear. According to the findings, cutting speed, feed rate, and depth of cut varied surface roughness by 1.9%, 78.3%, and 14.04%, and tool wear by around 43.8%, 37.9%, and 6.3%, respectively. The outcomes can be useful to metal-cutting industries to identify the combination of machining parameters with vegetable oil-based MQCL.

Experimental Study on Carbon Fiber-Reinforced Composites Cutting with Nanosecond Laser.

The carbon fiber-reinforced composite (CFRP) has the properties of a high specific strength, low density and excellent corrosion resistance; it has been widely used in aerospace and automobile lightweight manufacturing as an important material. To improve the CFRP cutting quality in the manufacturing process, a nanosecond laser with a wavelength of 532 nm was applied to cut holes with a 2-mm-thick CFRP plate by using laser rotational cutting technology. The influence of different parameters on the heat-affected zone, the cutting surface roughness and the hole taper was explored, and the cutting process parameters were optimized. With the optimized cutting parameters, the minimum value of the heat-affected zone, the cutting surface roughness and the hole taper can be obtained, which are 71.7 μm, 2.68 μm and 0.64°, respectively.

Prediction of Surface Roughness in Turning Applying the Model of Nonlinear Oscillator with Complex Deflection

This paper deals with prediction of the roughness of a cutting surface in the turning process, applying the vibration data of the system. A new type of dynamic model for a workpiece-cutting tool system, appropriate for vibration simulation, is developed. The workpiece is modelled as a mass-spring system with nonlinear elastic property. The cutting tool acts on the workpiece with the cutting force which causes strong in-plane vibration. Based on the experimentally measured values, the cutting force is analytically described as the function of feed ratio and cutting speed. The mathematical model of the vibrating system is a non-homogenous strong nonlinear differential equation with complex function. A new approximate solution for the nonlinear equation is derived and analytic description of vibration is obtained. The solution depends on parameters of the excitation force, velocity of rotation and nonlinear properties of the system. Increasing the feed ratio at a constant velocity of the working piece, the frequency of vibration decreases and the amplitude of vibration increases; increasing the velocity of working piece for constant feed ratio causes an increase of the frequency and a decrease of the amplitude of vibration. Experiments demonstrate that the analytical solution of the nonlinear vibration model in turning process is in direct correlation with the cutting surface roughness. The predicted surface roughness is approximately (1–2) × 10−3 times smaller than the amplitude of vibration of the nonlinear model considered in this paper.

Modeling of processing parameters for the cutting of rolled tungsten plates via abrasive water jet

Tungsten is a promising candidate for plasma-facing material in tokamaks. This study aims at determining whether the cut-surface roughness of rolled tungsten plates (RTPs) can be improved using an abrasive water jet (AWJ) through tests combined with modeling of the cutting-process parameters. Based on the key factors affecting the cut-surface roughness, the magnitude and type of test factors were increased, compared with the previous study. A batch test was designed and conducted to investigate the use of an AWJ to cut an RTP and obtain more comprehensive sample data. In addition, the multivariate linear regression method was employed to establish a multivariate quadratic response surface regression model of the relationship between the cutting-process parameters and the cut-surface roughness based on the roughness sample data. Moreover, a backpropagation (BP) artificial neural network (ANN) model was developed based on the cutting-process parameters to predict the cut-surface roughness. The two models were compared and experimentally validated, which showed that the BP ANN model exhibits relatively high accuracy. Thus, the established model can help to improve cut-surface quality and cutting efficiency.

Experimental analysis on waterjet-guided Nd: YAG laser thin wood machining

Waterjet-Guided Laser (WJGL) machining is an advanced technique providing efficiency and precision for wood machining. The present study investigates the practical demonstration and analysis of laminated object manufacturing (LOM) WJGL for thin wood machining. A theoretical process of wood laser cutting was established, expressing relations between the cut kerf width and the influencing parameters. WJG Nd: YAG laser system was utilized for machining Korean pine and Northeast China ash specimen of 3 mm thickness, each with 7.21 and 7.13% of water content, respectively, under different machining conditions. The effects of process parameters and influences on woodcut surface geometry were analyzed via analysis of variance (ANOVA) and scanning electron microscopy (SEM). The investigated parameters include the laser cutting speed, power, kerf width, heat-affected zone (HAZ), and cut surface roughness. The study shows that the kerf width and surface were significantly influenced by WJGL power, followed by the cutting speed. For both wood specimens, at a fixed laser cutting speed of 2.36 mm/s, the kerf width increases significantly with laser power, affecting the cut surface quality accordingly. At 6 W and 8 W, the cut kerf geometry and surface quality were excellent for the Pinus Koraiensis, with kerf widths of 0.79 and 0.852 mm, respectively. At a fixed laser power of 8 W, the kerf width decreases with the cutting speed, affecting the cut surface quality. At a cutting speed of 4.33 mm/s, an excellent cut surface of Fraxinus mandshurica was observed with 0.808 mm of kerf width. Depending on the machining conditions, the kerf width variations of Korean pine were more significant than the Northeast China ash. LOM-WJGL is an efficient and eco-friendly technique for thin wood processing.Graphical abstractArticle HighlightsPractical modeling demonstration of waterjet guided laser (WJGL) wood machining.Experimental investigation of different wood specimens under influenced process parameters and machining conditions.Characterization and identification of suitable wood types for efficient and eco-friendly applications.

CAD and FEM Modelling of Theoretical Roughness in Diamond Burnishing

Diamond burnishing is a widely used finishing machining that can have a positive effect on both the roughness of cut surfaces and its stress state. This paper is focused on the examination of the theoretical and real roughness of surfaces machined by sliding burnishing. In determining the theoretical roughness, the surface structure created by the pre-burnishing cutting (turning) was also considered. Two different modelling methods were used to obtain theoretical surface roughness data: CAD-modelling and finite element simulation. A method using CAD-based modelling of the machined surface was used to determine the theoretical roughness for both the turning and burnishing processes. However, this previously developed model is not directly applicable to plastic deformation processes such as diamond burnishing, so the principle of the Hertz theory for normal contact of elastic solids was used to calculate the penetration depth of the tool into the workpiece. The 2D FEM simulations were performed in the DEFORM software. To validate the applied modelling methods, real cutting experiments were performed, where the surface roughness values were measured during diamond burnishing experiments with different feed per revolution values. Based on the comparison of both applied modelling methods with real roughness data it can be stated that the theoretical roughness values are well approximated the real data.

Optimization of Surface Roughness and Material Removal Rate in Turning of AISI D3 Steel with Coated Carbide Inserts

The aim of this paper is to optimize the metal removal rate and surface roughness through turning on AISI D3 Steel with coated carbide inserts. As per the current market scenario, for the metal cutting industries the most important challenge in the turning process is to satisfy both requirements quality as well as high productivity in less time in order to remain competitive. Among all the different cutting processes, the turning process is one of the most applied and fundamental metal removal operations in the real manufacturing environment. This work examines the impact of machining factors like speed, depth of cut & feed on roughness and MRR of AISI D3 steel which have a hardness value of 60 HRC with coated carbide inserts. At high speed and feed rate optimum MRR was achieved and opposite to that at low feed and depth of cut optimum surface roughness was obtained. Taguchi L9 (3)3 OA has been applied for experimental design. ANOVA analysis is performed just after DOE to identify the significant factor which influences MRR and surface roughness. Among the three machining factors, depth of cut and speed has more influencing effect on roughness and the feed influences MRR. Effort was made to find optimum solution to minimize the roughness and maximize the MRR by Taguchi and ANOVA technique.

Evaluation of the effect of process parameters on the cut quality in fiber laser cutting of duplex stainless steel using response surface method (RSM)

Fiber laser cutting of stainless steel material is known as one of the most efficient cutting methods, with an acceptable quality and low production costs. Duplex stainless steels have higher chromium and molybdenum contents, making their thermophysical properties different in comparison to austenitic stainless steels; this can have a direct impact on the cut quality in the laser cutting process. In this research, the effect of such process parameters as cutting speed, focal length and laser power on the temperature adjacent to the cut kerf and cutting surface roughness was systematically investigated through the response surface methodology (RSM). The central composite design (CCD) was also used for the experimental design and analysis of variance (ANOVA), showing the effect of the participation of each factor on the responses. The laser power had the most significant influence on the temperature around the cut kerf by increasing the temperature from 180 to 500 °C, with the increase of the laser power from 700 to 1100 W. Increasing laser power continuously diminished the surface roughness about 45 percent. The minimum surface roughness value was recorded at the focal length of 0.4 mm, at which the laser energy density was at the highest level of 5100 W/mm2. Increasing the laser power up to 900 W, clearly improved the roughness although increasing power up to 1100 W has had a detrimental effect the surface roughness which was led to the creating some cavities and dross at the cutting surface.

Glass precision micro-cutting using spark assisted chemical engraving

Manufacturing industry faces new challenges with the emergence of the need for the production of small batches of personalized parts. Such production methods demand for a capability to integrate multiple machining operations in one manufacturing process to reduce setup and calibration time and tooling costs. This requirement is especially challenging for difficult-to-machine materials such as glass, since there exist only a limited number of glass machining technologies and further these technologies often require specialized tooling. Glass cutting is among the crucial machining operations, which is frequently required for glass products.The presented study discusses free-form micro-cutting by Spark Assisted Chemical Engraving (SACE), determining cut parameters, in terms of tool feed-rate F and depth-of-cut p in function of machining voltage. A simple model is discussed allowing to predict the maximal product F⋅p which can be used to cut glass by SACE. The presented data and model allow to reduce the time-consuming trial and error process in determining appropriate cutting parameters. An interesting finding is that lowest cutting times can be achieved with tools of 100-μm diameter. Cut surface roughness of initial cuts can be reduced by deploying subsequently incremental finishing (polishing) passes performed at lower machining voltage, lower tool feed rates and higher angular tool rotation. It is demonstrated that very smooth cut surfaces (Rz ~ 1 μm) can be achieved.

Nanosecond-Fiber Laser Cutting and Finishing Process for Manufacturing Polycrystalline Diamond-Cutting Tool Blanks

This paper presents a nanosecond-fiber-laser-based method for manufacturing polycrystalline-diamond (PCD) tool blanks. The effects of variations in the process path and operating parameters on the cut-surface morphology and surface-quality of the processed PCD workpieces have been analyzed. The results obtained in this study reveal the reactive fusion cutting mechanism to yield a processing depth of 155.2 µm at 30-W average laser power, 200-ns pulse width, and 30-kHz pulse frequency. The successful cutting of a 1.2-mm-thick PCD workpiece via implementation of the horizontal-shifting and vertical layer–by-layer processing methods is reported. Compared to the wire-electrical-discharge machining (WEDM), the proposed approach yields superior cut-surface roughness (Ra = 0.378 µm). Moreover, the laser processing was performed on a single-axis curved stage, on which the workpiece placed at an inclination during laser cutting and finishing. Thus, a PCD insert with an orthogonally cut edge, flat and pit-free finishing surface, and excellent tool-surface roughness (Ra = 0.202 µm) was obtained, thereby verifying the feasibility of the proposed approach. Furthermore, it is evident that the nanosecond-fiber laser can be used to not only cut and finish PCD inserts but also produce PCD workpieces oriented at different rake and clearance angles.