Assessment Of Surface Integrity Research Articles

Interaction of electric current with burnishing parameters in surface integrity assessment of additively manufactured Inconel 718

One of main problem associated with surface sever plastic deformation (SSPD) techniques like low plasticity burnishing (LPB) of metallic materials is limitation of surface integrity improvement at further loads (i.e. static force or pass number). It is due to interlocking of dislocation motion that limits further plastic deformation. As a plausible solution, in the present work, electric current assisted burnishing (ECAB) is introduced to use the concept of electroplasticity in surface integrity (roughness, hardness and residual stress) enhancement of Inconel 718 by additive manufacturing. Nevertheless, there are some researches which use this method to enhance performance of SSPD, the interaction effect of electrical parameter like current density with other parameters haven’t been studied well. Thus, to make the process optimized in terms of surface integrity aspects, parametric study of ECAB process with focus on interaction of current density with other LPB parameters merits further investigations. Thus, in the present work, an experimental study was carried out to identify the interaction effect of current density (as main parameter of ECAB) with other burnishing parameters (spindle speed, feed rate, current density, pass number and static force) on surface integrity aspects. Analysis of variances was further carried out to identify the contribution of each parameter on performance measures. Then, the interaction plots based on polynomial regression were developed, analyzed and discussed based on the physic of plastic deformation and some microscopic analysis like surface topography, scanning electron microscopy and X-ray diffraction analysis. It was found from the results that electric current density has the greatest effect on surface integrity aspect with contribution of 60 % on surface roughness, 68.5 % on hardness and 30 % on surface compressive residual stress. On the other hand it was found that this parameter has high interaction with process factors while applying different current density changes the optimum burnishing setting for each performance measures. Application of LPB at optimum parameter setting causes improvement of surface roughness of as-built material about 54 %; further improvement of 70 % and 85 % in roughness values were also achieved when the electric current with densities of 5A/mm2 and 10A/mm2, respectively were applied to burnishing process at optimum setting. It was also found that application of optimum LPB as well as optimum ECAB with densities of 5A/mm2 and 10A/mm2, results in improving the surface hardness about 17.5 %, 42 % and 68 %, respectively. In addition, under foresaid post-processing sequence, the surface compressive residual stress enhanced from 121 MPa (tensile type) for as-built material to −208 MPa, −345 MPa and −488 MPa (compressive type). Finally, the most optimum solution results in minimum surface roughness as well as maximum hardness and residual stress were identified by desirability approach function as 300RPM spindle speed, 0.08 mm/rev feed rate, 10A/mm2 current density, 3 pass number and 300 N force. To show the application of this optimization in a real life problem, fatigue resistance of optimum samples for high cycle and low cycle testing were obtained and compared with as-built material. It was found that following this post-treatment, the life cycle of samples improves from 160 % to 270 %, respectively that affirms practical application and manufacturing efficiency of proposed approach.

Surface Integrity of 20MnCr5 Laser Powder Bed Fusion parts subject to contact fatigue test

Additive Manufacturing (AM) is vital for industrial innovation, offering high potential for groundbreaking solutions. However, its successful implementation still depends on overcoming several challenges. Particularly, the assessment of surface integrity in AM-generated components, and its degradation when subjected to contact stresses presents an ongoing endeavor. Within this context, the current work delves into the study of the surface integrity of 20MnCr5 case-hardened samples manufactured through laser powder bed fusion (L-PBF), as well as delves into the investigation of surface failure progression when the samples are subjected to cyclic contact stresses. This study encompasses the analysis of residual stresses, hardness, and roughness of specimens manufactured through both additive and conventional production routes. The study’s findings show that it is feasible to attain analogous surface quality when proper finishing is applied to L-PBF samples. Although, despite the comparable surface quality, the contact fatigue performance was significative lower on the AM sample when compared to the conventionally manufactured. Additionally, additive manufacturing brings up new challenges to performance by presenting a heterogeneous stress distribution and sub-superficial porosity. In conclusion, to attain a desirable surface integrity for additive manufactured parts, further research should not only focus on improving the process parametrization but should also developing finishing routes especially oriented to additive manufacturing, considering therefore how the interaction between the manufacturing processes will evolve into a desirable surface integrity state.

Investigation of machining characteristics and surface integrity for trim cut WEDM of hybrid metal matrix composite [Al 6061, SiC, and TiB2

This study is focused on fabrication of Hybrid Al6061/SiC + TiB2 MMC by stir casting process, primarily to study the effect of two different reinforcement particles on mechanical properties and microstructure. Additionally, the assessment of surface integrity has been attempted after machining the composite by trim cut WEDM process. Five samples have been fabricated with varied weight fraction of SiC and TiB2 reinforcement, keeping total weight percentage of reinforcement particles fixed to 10%. It is observed that Hybrid MMC with composition Al6061 (90%), SiC (2.5%), and TiB2 (7.5%) shows better mechanical properties which is corroborated by both the optical microscopy and SEM. A screening experiment has been designed using fold over fractional factorial technique (with resolution IV), to investigate the parametric effects on surface integrity features, i.e., surface roughness, spark gap, and recast layer for trim cut WEDM operation. Peak current (Ip) and pulse on time (Ton) have been found to be the significant parameters for spark gap as well as surface roughness. It is observed that the trim cut operation improved the surface roughness and reduced it to 2.2 µm from 3.93 µm (after rough cut). Recast layer has been reduced to a value of 4.67 µm after trim operation, from 24.6 µm for rough cut. These findings suggest that trim cut strategy is very effective in improving the surface integrity of the rough-cut machined samples. It is also observed that thickness of recast layer is directly proportional to the discharge energy during trim cutting.

Ultrashort Pulse Laser Micromachining of Silicon: Effect of Repetition Rate and Assessment of Surface Integrity of Microchannels

Ultrashort Pulse Laser Micromachining of Silicon: Effect of Repetition Rate and Assessment of Surface Integrity of Microchannels

Assessment of surface integrity and hole quality in graphene-based NMQL Micro-drilling of ceramic-coated Nimonic 90 for gas turbine applications

Nickel-based superalloys have superior strength properties at higher temperature ranges and thus have become increasingly important in manufacturing gas turbine components for aerospace industry. However, the desire for a larger thrust-weight ratio has raised the typical operating temperature in a gas turbine; thus, thermal barrier coatings are essential. The present work compares the micro-drilling performance of ceramic-coated Nimonic 90 nickel superalloy under dry, flood and 0.5% graphene-based NMQL conditions. The biodegradable acid oil was used as a base oil, and the assessment comprised surface integrity in terms of surface roughness inside the hole and micro-crack formation and hole quality based on the diametrical overcut and taper ratio. Spindle speed (1000, 2000 and 3000 rpm) and feed rate (3, 6, and 9 μm/rev) were changed in three levels, and Taguchi L9 array was applied for the design and analysis of the experiments. Ti-Al-N coated tungsten carbide drill of diameter 700 μm was used, and Analysis of variance (ANOVA) revealed that spindle speed was the utmost important parameter impacting surface roughness, while speed and feed rate both influenced overcut and taper ratio. 0.5% Graphene-based NMQL lubrication condition significantly diminished the surface roughness by 52.67%, overcut by 46.86% and the taper ratio by 48.87% as compared to dry condition. Furthermore, in the NMQL condition, micro-crack development and ceramic layer damage were minimized, resulting in better surface integrity. In addition, burr development was minimized at the hole periphery, and tool wandering was not seen in the NMQL condition. Hence the hole quality was superior in NMQL conditions as compared to the dry and flood lubrication.

Analysis of surface integrity in drilling carbon fiber reinforced polymer composite material under various cooling/lubricating conditions

Carbon Fiber Reinforced Polymer (CFRP) composite materials are a class of advanced materials widely used in versatile applications, including aerospace and automotive industries, due to their exceptional physical and mechanical properties. Owing to the heterogeneous nature of the composites, it is often a challenging task to machine them unlike metals. Drilling in particular, the most commonly used process for component assembly, is critical especially in the aerospace sector that demands parts of highest quality and surface integrity. Conventionally, all composites are machined under dry conditions. While there are drawbacks related to dry drilling, for example, poor surface roughness, there is a need to develop processes that yield good quality parts demonstrating improved surface integrity. This study aims at investigating the machining performance when drilling CFRP composite material under cryogenic (Cryo), minimum quantity lubrication (MQL) and hybrid (CryoMQL) conditions and comparing the performance with dry drilling in terms of the thrust force, torque, delamination, geometric error such as diametric variation, and surface integrity assessment including average surface roughness, hardness and sub-surface damage analysis. Additionally, the effects of varying the feed on the drilling performance were examined. Based on the results, it was concluded that drilling of CFRP composite material using coolant/lubricant outperformed dry drilling by producing better quality parts. Also, varying the feed proved to be advantageous over drilling at constant feed.

Innovative X-ray diffraction and micromagnetic approaches for reliable residual stress assessment in deep rolled and microfinished AISI 4140 components

The residual stress state in the subsurface is a key element of surface integrity. It is well known to have a significant impact on a component's properties in terms of fatigue behavior and resistance to wear and corrosion. For this reason, adjusting residual stresses during manufacturing is a major challenge in modern production engineering, to improve and ensure a component's fatigue strength. In this context, hydrostatic deep rolling of the workpiece surface using adapted parameters enables the targeted induction of compressive residual stresses into subsurface layers. Due to specific properties regarding subsurface and topography for functional components in tribological applications, a further machining operation by microfinishing following deep rolling seems to be purposeful. In particular with regard to the production of components exposed to periodic load changes when used, the process combination can enable a substitution of the typically required conventional subsurface zone hardening. With the aim of economical process design, the corresponding parts can be manufactured with significantly reduced time and costs. Efficient and well-founded methods for monitoring the resulting influence on the subsurface zone properties are essential for a reproducible and target-oriented process design. The prevailing method for the non-destructive assessment of residual stresses in both academia and industry is X-ray diffractometry using the sin2 ψ-method. However, this method is time-intensive and requires complex instrumentation. Thus, efforts have been undertaken in past decades to develop alternative methods for the efficient and reliable characterization of residual stresses. In this research, the applicability of the cos α-method in X-ray diffractometry and a micromagnetic approach for residual stress assessment was investigated, analyzing deep rolled and microfinished AISI 4140 specimen conditions. In addition to the diffractometric and micromagnetic measurements, metallographic and topographic analyses of machined surfaces were carried out. Deep rolling was found to induce significant compressive residual stresses of up to −1100 MPa. After microfinishing of the deep rolled surfaces, favorable compressive residual stresses remain in the subsurface, reaching approximately up to −750 MPa. Based on this, the production of tailored surfaces with respect to a suitable combination of topography and subsurface is possible. For all surface states investigated, a good agreement between the two approaches in X-ray diffraction was found. Magnetic Barkhausen noise (MBN) measurements prove to be well applicable for an efficient and holistic assessment of surface integrity in the subsurface of deep rolled and microfinished AISI 4140 specimens.

Comparative assessment of machining induced hardening in HSM of Inconel 718 with aid of eco-friendly cutting fluids

Fulfilling the dual demand of better quality along with higher productivity, and further incorporating cleaner manufacturing processes so as to comply with governmental pollution control norms, have been subjecting manufacturers to intense pressure over the globe in recent times. In context of the same, present paper introspects the resulting surface integrity of the exotic superalloy Inconel 718 during high-speed turning under dry, water vapour, and chilled air being the eco-friendly machining environments by employing coated carbide tools at ideal process parameter settings. Furthermore, a focus has been placed on analyzing the effectiveness of cutting fluid supply techniques on to the machining zone using both traditional exterior nozzle and internally through tooling. Assessment of surface integrity was carried out in terms of machining induced hardening through degree of work hardening and nano-hardness variations beneath machined surface. Results showcased beneficial higher degree of work hardening for water vapour and chilled air as cutting fluids, with the prior having a more pronounced effect. Further the supply of cutting fluid through tool holder was advantageous in obtaining machined surfaces that are considerably more hardened as compared to that with cutting fluid delivered conventionally. Overall it was found that cutting fluid water vapour imparted better characteristic machining induced hardening as compared to machining under dry conditions and chilled air.

Hole geometry and surface integrity assessment in drilling of inconel 718 using laser texture filled solid lubricant tools

Purpose Inconel 718 is used in gas turbine engines for aerospace applications due to high creep resistance but generating a hole with good surface integrity is challenging because the γ′′ interface is very strong so that slip is difficult in the grain boundary. So, the purpose of this work is to enhance the performance of drilling using a micro texture drill tool filled with solid lubricant. Design/methodology/approach Three different micro textures such as star shaped with 6-sharp apex, rectangular slots parallel and perpendicular to drill axis are created using laser on the drill tool. Deep cryogenic treatment is done on the textured tool to improve the strength and wear resistance before it is filled with solid lubricant. A detailed experimental investigation is performed to analyse the hole geometry and surface integrity of the drilled hole. Findings The accuracy of the drilled holes is enhanced in the star shaped texture drill tool over other textured and non-textured tools. A significant improvement in surface finish and hardness are observed and moreover cylindricity error, burr height of the hole is less for the above condition. It is also inferred that, at lower feed rate and higher speed produce hole with an accuracy of 96%. Originality/value Aerospace industry is focussing on improving the hole geometry and surface in Inconel 718. This work demonstrates the novel technique to improve drilling of Inconel 718 using laser textured tool filled by the solid lubricant.

Performance of laser surface textured cemented carbide tools during abrasive machining: Coating effects, surface integrity assessment and wear characterization

Laser surface texturing (LST) and coating deposition are implemented on cemented carbide (WC-CoNi) tools to extent their application in abrasive-like machining processes. The topographic features of a conventional cubic boron nitride based honing stone are achieved by LST, whereas wear resistance is enhanced by deposition of a ceramic layer. Three tool types are considered here: uncoated and coated LST WC-CoNi tools, besides a honing stone used as reference. They are tested under abrasive-like cutting conditions using an in-house workbench and a workpiece made of 20MnCr5 steel. Wear resistance and mechanisms as well as surface integrity of the tools after cutting tests are evaluated. It is found that LST cemented carbide tools achieve similar material removal effectiveness to the honing stone. Furthermore, coated LST tool exhibits a better cutting capacity, in terms of machined workpieces with smoother surfaces and enhanced wear resistance. However, the cutting process using cemented carbide tools is not as stable as the one developed employing the honing stone. The different response is related to the tribological conditions of the cutting edges of the laser-shaped pyramids. Damage within constitutive microstructural phases is clearly reduced for the coated condition, although it is still directly related to geometrical complexity of the pyramids.

A digital approach to automatically assess the machining-induced microstructural surface integrity

When it comes to advanced materials for safety-critical applications, the evaluation of the machining-induced microstructural surface integrity represents a primary aspect within the assessment of part quality. Nowadays, presence and extent of machining-induced microstructural anomalies in the workpiece subsurface is manually measured by human inspection of digital micrographs. In the present work, computer-based performance of this task is achieved through a set of algorithms designed to automatically identify microstructural anomalies resulting from material removal operations. Digital surface integrity assessment has been demonstrated with application to scanning electron micrographs exhibiting different levels of microstructural deformation and obtained under different imaging conditions. Furthermore, the digitally detected material condition has been investigated with the support of in-depth field emission gun scanning electron microscopy (FEG-SEM) and electron backscatter diffraction (EBSD) analysis. This has allowed the relationship between the material evidence observed through different strategies to be established. Finally, the set of algorithms has been applied to study the microstructural condition of a large material region, by performing sequential processing of a series of micrographs. In this way, the measurement procedure has been calibrated and its capability to perform surface-integrity evaluation on large areas in an automated and standardised way has been demonstrated.

Relating MR relaxation times of ex vivo meniscus to tissue degeneration through comparison with histopathology

Quantitative magnetic resonance imaging (MRI), e.g. relaxation parameter mapping, may be sensitive to structural and compositional tissue changes, and could potentially be used to non-invasively detect and monitor early meniscus degeneration related to knee osteoarthritis. To investigate MR relaxation times as potential biomarkers for meniscus degeneration through comparisons with histopathology. We measured MR relaxation parameters in the posterior horn of 40 menisci (medial and lateral) at a wide range of degenerative stages. T1, T2 and T2* were mapped using standard and ultrashort echo time sequences at 9.4 T and compared to gold standard histology using Pauli's histopathological scoring system, including assessment of surface integrity, collagen organization, cellularity and Safranin-O staining. All three relaxation times increased with total Pauli score (mean difference per score (95% CI) for T2*: 0.62 (0.37, 0.86), T2: 0.83 (0.53, 1.1) and T1: 24.7 (16.5, 32.8) ms/score). Clear associations were seen with scores of surface integrity (mean difference per score for T2*: 3.0 (1.8, 4.2), T2: 4.0 (2.5, 5.5) and T1: 116 (75.6, 156) ms/score) and collagen organization (mean difference between highest and lowest score for T2*: 5.3 (1.6, 8.9), T2: 6.1 (1.7, 11) and T1: 204 (75.9, 332) ms). The results were less clear for the remaining histopathological measures. MR relaxation times T1, T2 and T2* of ex vivo human menisci are associated with histologically verified degenerative processes, in particular related to surface integrity and collagen organization. If confirmed in vivo, MR relaxation times may thus be potential biomarkers for meniscus degeneration.

Assessment of Surface Integrity in Diamond Grinding – Based Hybrid Machining of Tungsten Free Carbide based Hard Metal

Hybrid machining process comprises of applying at least two process components all the while or successively in synergistic way to improve the machining performance. One such machining process is diamond grinding in presence of high frequency electric sparks. This process is all about making trade-off between surface finish and process efficiency. This paper attempts to model the surface roughness using artificial neural network with supervised learning in which back propagation algorithm is used for minimizing error and estimation of adaptive weights. Experimental data for machining of TN20 Russian grade cermet is used for development of neural network.

Surface integrity assessment of laser treated and subsequently coated cemented carbides

Cemented carbides, referred to as hardmetals, are forefront engineering materials widely implemented in industry for chip-removal cutting tools and supporting parts. As a newly developed technology for surface modification with high precision, the application of short pulse laser may extend the utilization of cemented carbides. However, surface integrity of laser-treated materials may be affected during the ablation phenomena. These potential changes may also be relevant for subsequent coating deposition, a surface modification stage usually invoked in many cutting and forming tools. It is the objective of this work to study the influence of a previous laser treatment on the surface integrity of a cemented carbide grade, finally coated by a ceramic layer introduced by physical vapor deposition. In doing so, a nanosecond laser has been employed. Surface integrity is assessed in terms of roughness, hardness, and microstructural changes induced at the subsurface level. It is found that pulse laser can effectively remove the target material, resulting roughness being similar to that attained by abrasive grinding. Although some subsurface damage is observed, it is limited to a very shallow layer, this being thoroughly eliminated during sandblasting implemented before coating deposition. Relative hardness increase is larger for laser treated substrate than for just polished one, reason behind it being speculated to come from the sandblasting stage used for removing damaged layer.

Surface integrity assessment of M3 HSS cutting taps after grinding at various machining conditions

Grinding is a machining process that provides a combination of good surface finishing and tight dimensional tolerances on a machined component. Owing to these characteristics, it is employed in the finishing process of hardened parts, such as high-speed steel (HSS) cutting tools (principally drills and taps). Despite the various benefits, the specific energy in grinding is very high, resulting in high heat generated in the wheel–workpiece interface that could lead to thermal damages. To avoid such problems, aiming to maximize productivity and preserve the integrity of the machined component, a cutting fluid and cutting parameters must be properly selected. However, since the process dynamics is particular for each grinding process, especially in complex geometries, specific studies in real manufacturing conditions are required to understand the phenomena and minimize surface damages. In this context, this work aims to evaluate the surface integrity of M3 HSS cutting taps after they have been ground at various cutting conditions. Machining tests were performed in situ under controlled and variable wheel speed, depth of cut, and workpiece speed conditions. Machined surface images and microhardness below the surface were the output variables investigated. Results showed that, on average, the thickness of the affected surface layer was about 70% lower after machining at the lowest workpiece speed used. The correlation between grinding removal rates and thermal damage was also discussed.

Ablation Investigation of Cemented Carbides Using Short-Pulse Laser Beams

As an excellent engineering tool material, cemented carbides are capable to shape and cut metallic materials with high surface finish quality and precision. However, in regard to conventional abrasive methods cemented carbides are difficult-to-machine materials due to their extreme hardness combined with relatively low toughness. In contrast, laser beam machining is an advanced non-contacting cutting method which is therefore suitable for shaping hard materials. In particular, the application of short-pulse laser beams enables the cutting of hard materials meeting high precision requirements. Moreover, it can effectively reduce defects induced by mechanical contacts and thermal reactions. In this paper, a general study of the ablation mechanism of cemented carbides using short-pulse laser is conducted. Special attention is paid to the correlation between the material ablation and machining parameters within the nanosecond regime: pulse number and pulse energy. In doing so, two cemented carbide grades with similar composition but different grain size have been chosen as investigated materials. An experimental set-up equipped with a nanosecond laser and an auto-stage is implemented to produce dimples on the cemented carbide surfaces with variable pulse number and pulse energy. The experimental design and characterization of geometrical features of produced dimples are presented and discussed. The work is complemented with a thorough surface integrity assessment of the shaped materials. It is found that ablation increases proportionally with the pulse number and applied energy. Regarding microstructural effects, ablation is discerned to be more pronounced in the coarse-grained grade as compared to the medium-sized one.

Material Characterization using Barkhausen Noise Analysis Technique - A Review

Background/Objective: Material characterization is an essential part during manufacturing cycle of component as it assesses the surface integrity of component. Assessment of surface integrity is important since it decides the fatigue strength and service life of manufactured component. Microhardness, microstructure and residual stress are key elements of surface integrity. Modern manufacturing industries relies on laboratory based technique such as microhardness tester, optical metallographic inspection and X-ray Diffraction (XRD) techniques for measurement of key elements of surface integrity. The laboratory based techniques are not eco-friendly and as well as time consuming. Methods/Statistical Analysis: Barkhausen Noise (BN) analysis is a preferred and advanced technique for material characterization when an external magnetic field is applied over a ferromagnetic material, it changes the global magnetization occurs by motion of magnetic domain wall as these domain wall align these stress in the direction of applied magnetic field. A voltage pulse is generated due to motion of magnetic domain, which can be detected as signal by sensor. This included voltage pulse is known as BN signal. Findings: Conventional material characterization techniques such as hardness tester, optical microscopic and XRD are extensive time consuming laboratory based technique and difficult to integrate in manufacturing environment. On the other hand, BN technique is less costly, fast, eco-friendly NDT which can be easily integrated with manufacturing cycle for component. Application: Barkhausen Noise measurement is generally associated with hysteresis loop measurement.BN signal parameters such as Root Mean Square (RMS) value, amplitude, peak position as well as hysteresis loop properties coercively, remanence are sensitive towards change in micro-hardness, microstructure In this way, BN analysis technique can assess the surface integrity of manufactured component. In the present review paper, a critical and wide literature survey is conducted to summarize and highlight the successful attempts of BN techniques for surface integrity assessment of components, by using various manufacturing process such as machining, welding, heat treatment and grinding.

High-feed turning of AISI D2 tool steel using multi-radii tool inserts: Tool life, material removed, and workpiece surface integrity evaluation

ABSTRACTMulti-radii tool inserts offer novel configuration that comprises of multiple radii at tool nose. A review of the available literature indicates that there exists a need for experimental investigation on certain key machining characteristics of such tools. This paper reports on tool wear/life, material removed, and workpiece surface roughness when multi-radii mixed alumina TiN coated tool inserts are employed for turning D2 steel. Inserts of three different nose radii (0.40, 0.80, 1.20 mm) at six levels of feed rates (ranging from 0.157 to 0.562 mm/rev) are used. Results show that flank wear is the dominant wear mode with catastrophic tool failure occurring at highest nose radius (1.20 mm) and feed rate (0.562 mm/rev) combination. Also, there is ∼59% reduction in tool life accompanied by ∼62% increase in quantity of material removed as the feed rate increases from 0.157 to 0.562 mm/rev at maximum nose radius (1.20 mm). Feed rate is found to be statistically significant factor for all three responses considered herein at 95% confidence level. Surface integrity assessment at maximum feed rate reveals presence of a strain hardened layer extending to the depth of 150 µm below the machined surface without any observance of white layer for all the tool conditions and nose radius.

Importance and Methods of Residual Stress Profile Measurement

The contribution is dedicated to surface integrity assessment of components from the point of view of residual stress profile after machining and finishing technologies. Residual stresses play the key role for dynamic life and service reliability of the part, especially rotating aircraft airfoils made of titanium and nickel base alloys. Except a brief summary of measurement methods practical experience with application of Beam deflection method combined with electrolytic etching is published. Specific measurement results for real aircraft Ti6Al4V airfoils and Ti6Al4V plates following its manufacturing technology are the subject of experimental part.

The use of computational fluid dynamics in the analysis of fluid flow and thermal aspects in grinding

A numerical model based on computational fluid dynamics is developed to analyze fluid flow and thermal aspects in grinding. The model uses multiphase fluid flow with heat transfer based on the volume-of-fluid method, convection, conduction in solids and a multiple reference frame model of the porous grinding zone. Fluid velocity vectors, useful flow rate, grinding temperatures and energy partition are predicted using the model. In lieu of direct measurements of these quantities, the verification relies on the indirect assessment of surface integrity. The simulation results provide adequate agreement with the measured residual stress, depth of heat-affected zone and full width at half maximum profile with respect to the grinding temperatures.