Ball Burnishing Research Articles

Enhancing surface integrity of additively manufactured Inconel 718 through numerical modeling of hydrostatic ball burnishing parameters using TOPSIS and ANOVA

Abstract Surface enhancement of laser powder bed fusion components is pivotal for their suitability in end-use applications. Hydrostatic ball burnishing, a mechanical surface hardening technique, induces compressive residual stress on the surface by the application of hydraulic force resulting in improved fatigue life of the material. This present study focuses on determining the optimum burnishing parameter combinations for better surface integrity (roughness, hardness, and residual stress) utilizing ANOVA and TOPSIS analysis. The cumulative performance score of the TOPSIS analysis states that the best parameter combination for Inconel 718 is found to be 300 bar pressure, 0.2mm burnishing width, and feed 800mm/min. The adjusted R² values of the ANOVA model for all three responses are 0.96, 0.93, and 0.94, confirming their close agreement with experimental results. With optimum parameters, the roughness decreased from 2.217μm to 0.305μm, Microhardness increased from 318.9HV to 475.9HV and residual stress was converted from tensile 216MPa to Compressive -54MPa demonstrating the significance of this process on surface enhancement.

FEM Investigation of the Roughness and Residual Stress of Diamond Burnished Surface

Characterization of surface integrity is possible with three critical metrics: microstructure, surface roughness, and residual stress. The latter two are discussed in this paper for low-alloyed aluminum material quality. Ball burnishing is a regularly used finishing procedure to improve surface roughness, shape accuracy, and fatigue life, taking advantage of the fact that it can favorably influence the variation in stress conditions in the material. The effect of burnishing is investigated using finite element simulation with DEFORM 2D software using the real surface roughness of the workpiece. The FEM model of the process is validated with experimental tests, the surface roughness is measured using an AltiSurf520 measuring device, and the residual stress is analyzed with a Stresstech Xstress 3000 G3R X-ray diffraction system (Stresstech, Vaajakoski, Finland). The results indicate that the burnishing process improves the surface roughness and stress conditions of AlCu6BiPb low-alloyed aluminum, and the study shows that there is good agreement between the FE and experimental results, further revealing the effect of the process parameters on the distribution of the compressive residual stress.

Evaluation of optimized surface characteristics in non-rotational sliding ball burnishing

ABSTRACT Non-rotational sliding ball burnishing (NRSBB) was developed as a polishing process. The effect of NRSBB parameters on longitudinal and transverse roughness (Ra || & Ra ⊥), and microhardness (MHV) of AA7075-T651 face-milled plate was investigated by response surface methodology. Ra || decreased by increasing the ball diameter. Ra ⊥ increased with increasing the burnishing depth and step over. MHV was enhanced by increasing burnishing depth and passes. The optimal parameters obtained from multi-objective optimization were the ball diameter of 10 mm, burnishing depth of 0.18 mm, step over of 0.062 mm, five passes, and feed rate of 1050.3 mm/min. Compared with the face-milled surface, the optimized NRSBB improved Ra ||, Ra ⊥ and MHV by 93.7%, 89.3% and 37.3%, respectively. The topographic parameters of Sa, Sq, Sp and Sv improved by 89.3 %, 87.5%, 76.4% and 88.9%, respectively. The microhardness distribution of the optimized sample indicated 600 μm hardened depth.

Surface integrity and high-cycle fatigue life of direct laser metal deposited AISI 431 alloys modified by plasticity ball burnishing

Laser metal deposition (LMD) as an additive manufacturing (AM) is widely used to repair and extend wear and fatigue life of the critical components. This paper has investigated the application of ball burnishing (BB) to improve surface integrity and high-cycle fatigue resistance of LMDed AISI 431 alloys. Results showed that the BB treated samples exhibited significant surface finish improvement by lowering roughness by 91 %. Microhardness increased from 490 to 530 HV0.1, an increase by 10 % with a modified depth of 400 µm from the top surface. XRD results showed a peak shift and increase in FWHM by up to 17 %. This had been corroborated by EBSD exhibiting a 20 % increase in dislocation density and 24 % increase in localised misorientation within microstructure. As a result, the overall high cycle fatigue strength of the burnished sample increased by 50 %, and the cracks initiated from sub-surface level defects at a depth of 350 μm below the top surface, delaying the crack propagation and fracture failure. The findings clearly highlight that the burnishing treatment can be a plausible approach in improving the dynamic fatigue resistance and the overall service life of LMDed AISI 431 steel alloys components in engineering applications.

A comparative investigation on the surface characteristics of AISI 304 and AISI 1045 steel influenced by turning combined with ball burnishing

Burnishing is a popular superfinishing procedure in the manufacturing industry that induces plastic deformation to the finished product by the application of a highly polished and hardened deforming element known as a burnishing tool. Research work on the burnishing process is numerous. However, the reports containing the comparative investigations are lacking. In this work, the effect of ball burnishing parameters namely penetration depth, burnishing spindle speed, and number of passes has been compared and analyzed on AISI 1045 and AISI 304 steels with respect to surface roughness, hardness, wear resistance, and corrosion resistance. Results indicate that the combination of a feed rate of 0.12 mm/rev, spindle speed of 160 rpm, and penetration depth of 0.025 mm with four passes generated minimum surface roughness (AISI 1045). However, maximum surface hardness is obtained with a feed rate of 0.12 mm/rev, spindle speed of 160 rpm, and at 0.085 mm penetration depth under one pass (AISI 304). The lowest specific wear rate is achieved with a feed rate of 0.12 mm/rev at a spindle speed of 160 rpm and a penetration depth of 0.085 mm in one pass (AISI 304). The burnishing process influenced both materials, AISI 304 and AISI 1045, under varying parametric conditions. The maximum reduction in surface roughness is 68.1% for AISI 304 and 79.3% for AISI 1045, while surface hardness improves by 27% for AISI 304 and 22% for AISI 1045. Additionally, the burnishing process reduces the specific wear rate by 49.3% for AISI 304 and 45.4% for AISI 1045. The refinement of grains during the burnishing process enhances corrosion resistance compared to the unburnished surface.

Fatigue strength improvement of aluminum alloy with surface defect by ball burnishing

AbstractBall burnishing (BB) is a surface finishing process that involves moving the tool while pressing it against the workpiece under rolling contact. We investigated the effects of BB on the fatigue strength of an aluminum alloy with a semicircular slit simulating an initial surface defect. After performing BB under a typical condition, compressive residual stress was induced to a depth of 0.4 mm, with a reduction in surface roughness by 81%. Consequently, the fatigue strength increased by 22%. BB prevented the fatigue strength reduction caused by the 0.1 mm deep slit. The result indicated that BB could render the below 0.1 mm deep surface defect harmless in terms of fatigue strength. The maximum depth of surface defect that can be rendered harmless is 0.18 mm according to fracture mechanics, which is in agreement with the experimental results.

A Synergistic Approach Combining Surface Enhancement and Buckling Modes for Improved Axial Crushing Performance of Thin-Walled Tubes

Abstract In this study, thin-walled tubes were circumferentially strengthened by plasticity ball burnishing of critical locations determined from buckling mode analysis. Axial crush test results revealed that the surface-treated (ST) tubes increased localized yield strength, attained superior crashworthiness performance, and triggered predictable deformation modes according to the buckling modes of the tubes. Numerical analysis was performed and successfully validated with the experiment at 90% prediction accuracy. The treated tube ST-4 with the 12th buckling mode outperformed a conventional tube with an increase in specific energy absorption (SEA) and crush force efficiency (CFE) by up to 70% while sustaining a low increase in initial peak force (IPF). Furthermore, the tube demonstrated a greater rate of energy dissipation compared to tubes with conventional surface-treated patterns at the same level of surface-treated area. The crashworthiness performance improved as the surface-treated area ratio increased. A theoretical model was developed for the surface-treated tube based on fundamental deformation kinematics, predicting mean crushing force and total energy absorption with acceptable accuracy. The findings strongly suggest that the proposed surface-enhanced tubes have great potential to be used as energy-absorbing structures in crashworthiness applications.

Corrosion protection of highly porous titanium by surface engineering

The corrosion resistance of highly porous titanium in a 20 % HCl solution was investigated using various surface engineering methods, including ball burnishing (BB) and gaseous nitriding (GN) below the polymorphic transformation temperature (α + β) and their combination (DDT). SEM, EDS, XRD, as well as micro- and nano-hardness testing methods, were employed to assess the microstructure of the formed barrier layers and determine their depth. After treatments, the corrosion was significantly reduced, with the corrosion current density being 8.7 to 25 times lower compared to the initial state of highly porous titanium. The results suggest that a DDT yielded the most substantial enhancement in the corrosion resistance of highly porous titanium.

Biodegradation performance of ball burnished magnesium alloy in stimulated body fluids for bioresorbable implant applications

Magnesium alloys are found to be potential bioresorbable materials. However, the application range of these alloys as bioresorbable materials has been limited due to rapid degradation in physiological fluids. The current study deals with the enhancement of degradation behavior of Mg Ze41A alloy in SBF solution by ball burnishing. Further, the influence of burnishing parameters on biodegradation rate has been investigated by Tafel plots, polarization resistance, electrochemical impedance spectroscopy and surface morphology analysis of degraded samples. Additionally, the biodegradation rate has been estimated by ANFIS modeling. The biodegradation rate of Mg Ze41A has been reduced from 1.106 mm/yr to 0.367 mm/yr with an improvement of 68.82% at optimum burnishing condition of burnishing force 50 N, burnishing speed 1400 RPM, burnishing feed 125 mm/min and 2 passes. ANOVA analysis has revealed that burnishing force and feed have contributed the most for the enhancement. The shift in degradation potential towards noble direction and reduction in degradation current density in potentiodynamic polarization curves and the highest charge transfer resistance in electrochemical impedance spectroscopy of the burnished samples are observed for burnished samples. The results reveal that ball burnishing process is a potential surface modification method in reducing the biodegradation rate of Mg Ze41A alloy. The ball burnishing has resulted in lowest biodegradation rate at a degradation current density of 5.743 μA/cm2 and degradation potential of −1.513 V. The ANFIS model developed with 81 fuzzy rules and triangular membership function estimated the biodegradation rate with an accuracy of 95.03%. The decrease in biodegradation rate of ball burnished magnesium substrate in SBF is essentially due to cumulative effect of compressive residual stress, microhardness, surface finish, work hardening and grain refinement.

Surface integrity and fatigue behavior of AISI 4340 steel after hybrid laser-ultrasonic assisted ball burnishing process

The final surface modification processes enhance the fatigue strength, wear resistance, and corrosion resistance of the workpiece by improving the surface quality, enhancing the microhardness, generating compressive residual stresses on the surface, and creating favorable changes in the microstructure. In this regard, using processes with different mechanisms is regarded as an optimal method to increase the efficiency of the final surface modification processes. This research seeks to experimentally investigate the hybrid laser-ultrasonic assisted ball burnishing (LUAB) process and its effect on the surface integrity and fatigue strength of 4340 alloy steel. The effect of the process on the sample’s microstructure was evaluated by the images obtained from the optical microscope and SEM. Further, the parameters of mean surface roughness and microhardness, as well as the results of the uniaxial tensile test and fatigue test of the workpiece were evaluated. In the case of using appropriate parameters in the process, the results indicated a 93.38% reduction in mean surface roughness and an increase of surface microhardness by 3.4 times compared to the initial sample. Additionally, the investigation of microstructure revealed the accessibility of homogeneous and refinement martensitic structures without surface melting. The results of uniaxial tensile and fatigue tests indicated a 6.29% increase in tensile strength and a 20.71% increase in the endurance limit of the treated sample (LUAB) compared to the initial sample. Finally, the results also showed a change in the fracture mode in the uniaxial tensile test and a reduction in the final fracture area in the fatigue test.

Evolution and anti-fatigue mechanism of surface characteristics of Ti60 alloy induced by ball burnishing and shot peening during tensile-compression fatigue

To clarify the evolution of surface characteristics of Ti60 alloy induced by ball burnishing and shot peening and their anti-fatigue mechanism during tensile-compression fatigue, room temperature and 450℃ elevated temperature fatigue tests were conducted on burnished and shot peened round bar Ti60 samples. Residual stresses, microhardness, and microstructures were analyzed during fatigue, and the fracture mechanism was investigated through fractography. The results show that the residual stress relaxation rate of the burnished sample is lower than that of the shot peened sample. After fatigue, the strengthened samples showed reduced microhardness and fewer low angle grain boundaries. The strengthened samples are both subsurface initiation, and the depth of initiation of the burnished sample is greater than that of the shot peened sample. The fatigue initiation mode at room temperature and 450℃ high temperature is quasi cleavage. No fatigue striations are observed at room temperature fatigue propagation zone, but they can be observed at 450℃ elevated temperature. The dimples can be observed at room temperature fatigue transient fracture zone. However, at 450℃ elevated temperature fatigue transient fracture zone, the dimples and quasi-cleavage can be observed simultaneously, indicating a mixed fracture mode. In addition, the crack shape of the strengthened sample is a wide top and narrow bottom shape due to the compressive residual stress layer.

Computer-Aided Analysis of the Formation of the Deformation Zone in the Burnishing Process

The study presents the use of spatial imaging of the shape of the deformation formation area occurring at the point of contact between the burnished tool and the processed material surface in the burnishing process. In the analysis of changes in the shape of surfaces processed by ball and disc pressure burnishing, an integrated measurement station was used to measure surface stereometry (New Form Talysurf 2D/3D 120 by Taylor Hobson) and to carry out a series of axially shifted roundness measurements (Talyrond 365 by Taylor Hobson). The geometric parameters of the deformation zone determined in the direction of the circumference of the cylindrical surface (direction of the main movement) and in the axial direction (in the feed plane) are presented. The data obtained as a result of metrological measurements were analysed using specialized computer software.

Effect of ball burnishing process on surface roughness and corrosion behavior of S235JR steel

Effect of ball burnishing process on surface roughness and corrosion behavior of S235JR steel

Effect of ball burnishing on surface roughness, wettability, mechanical integrity and antifouling resistance of UHMWPE

The aim of this paper is to investigate the effect of plasticity burnishing on the surface properties and antifouling resistance of UHMWPE. Ball burnishing experiments at different pressures (44–131 bar) and path strategies (1: Single Parallel and 2: Cross Parallel) were conducted. The treated surface was characterised in terms of surface roughness, surface topography, and contact angle (CA) to evaluate its surface wettability. Microhardness, wear and impact resistance were measured to assess mechanical integrity. Results show that as the burnishing pressure increased, surface roughness decreased. Strategy 2 demonstrated the most significant reduction in surface roughness. No clear relationship between burnishing pressure and CA was found. However, Strategy 2 with relatively higher pressure generated specific surface micro-texture that was responsible for higher CA over Strategy 1. Marine salt spray tests demonstrated improved water adsorption stably, creating a uniform hydration layer on the surface treated with Strategy 2. Consequently, in-field marine fouling test results revealed an improved antifouling resistance of the burnished surface. The burnishing increased microhardness, wear and impact resistance. Improvement in surface integrity was attributed to stretching and plastic yielding of entangled macromolecular chains and crystals networks in UHMWPE. The findings indicate that ball burnishing with appropriate path pattern and pressure could be a viable route to improve surface wettability and antifouling resistance.

Fatigue enhancement and hardening effect through ultrasonic vibration‐assisted ball‐burnishing process on AISI 1045 steel

AbstractThis paper aims to present a study of the effects of ball burnishing with vibration assistance on the bending fatigue endurance of cylindrical specimens subjected to bending stress and obtain the best input parameters. The specimens were burnished through six different combinations of preload force, number of passes, and vibration assistance, finding that burnishing while applying a 90‐N preload, five passes, and the addition of vibration assistance results in larger fatigue strength. In terms of roughness, it has been proved that vibration‐assisted ball burnishing reduces the mean roughness up to 90%, while enhancing the skewness and kurtosis parameters. The softening effect while deforming, caused by the vibration assistance, helped to reconstruct the surface, obtaining higher depths of affectation and hardening. Fatigue strength was improved by a 6.54% by only adding vibration assistance to the ball‐burnishing process.

Formulation and Comparison of Experimental based Mathematical Model with Artificial Neural Network Simulation on Surface Roughness with Burnished Spherical Surface Tool on Aluminum Alloy6351

This paper deals with the effect of burnishing process on the Aluminum Alloy material 6351(HE 15) using Lathe. Surface roughness generated after the turning operation was used to ball burnishing. The surface roughness pattern which was further used to simulate ball burnishing process using ANN. Improvement in the surface roughness values achieved for tool steel after ball burnishing process was 98.2429%.

Finite element analysis of ball burnishing: evolution of residual stresses and surface profile in Ti-6Al-7Nb alloy

In the present study, the effect of feed on the residual stress distribution and surface profile generated during the ball burnishing of titanium alloy (Ti-6Al-7Nb) was investigated using finite element simulation. The elastic-plastic material model with isotropic hardening was used for performing the simulations. The created finite element model containing a rigid ball and deformable specimen was optimized and validated using experimental data. It was observed that the effect of burnishing feed is significant on the surface profile compared to residual stresses. The maximum residual stress obtained during the simulation of the process was achieved for the burnishing feed of 0.2 mm. This confirmed the variation of residual stress when the burnishing feed is varied. Whereas the surface roughness was the least for the 0.05 mm burnishing feed which was due to uniform deformation of the surface during the process.

Ensuring the functional performance of the cylinder liner at the finishing processing stage

The article considers the use of a centrifugal ball burnisher in the hardening finishing operations of machining the cylinder liner of a marine small-sized diesel engine of the 4Ч9,5/11 type. The use of a burnisher provides high hardness and low surface roughness and residual stresses, which have a compressive positive effect on the surface layers of the product. Keywords: diesel engine, cylinder liner, roughness, hardness, burnisher. nurik909@mail.ru

Improving Wear Resistance of Highly Porous Titanium by Surface Engineering Methods

The wear resistance of highly porous titanium in the tribo-pair with bronze under boundary lubrication condition was investigated. According to analyses of worn surfaces of highly porous titanium, it was shown that the main reason of poor wear resistance were subsurface pores that led to nucleation of micro-cracks in the subsurface layer and thereby intensified fatigue (delamination) wear. For improvement of wear resistance of highly porous titanium, the surface engineering methods, such as deformation (ball burnishing, BB), diffusion (gas nitriding, GN), and their combination—deformation–diffusion treatment (DDT), were considered. It was shown that surface hardening of highly porous titanium by BB, GN, and DDT reduces the weight wear intensity and the friction coefficient of the tribo-pairs by 1.4, 3.5, 4.0 and 1.8, 2.3, 3.2 times, respectively. Such an improvement in the tribological properties of highly porous titanium after surface hardening is explained by changes in the main wear mechanism of the tribo-pairs from adhesive and fatigue to abrasive. The highest wear resistance of highly porous titanium was observed after surface deformation–diffusion treatment, as this treatment provides a combination of the positive effects of both ball burnishing (closing of surface pores) and nitriding (formation of a surface chemically inert and hard nitride layer).

Investigation on tribological characteristics of ball burnished Mg Ze41A alloy by ANOVA and ANFIS techniques

Magnesium (Mg) alloys exhibit superior strength, high castability and machinability. But, the application range of Mg alloys was limited because of low wear and corrosion resistance. Also, Mg alloys are being explored for biomedical applications due to their biocompatibility and biodegradability nature. The wear behavior of Mg alloys can be enhanced by mechanical, physical and chemical methods. This study deals with deployment of one of the mechanical methods such as ball burnishing on Mg Ze41A alloy. The contribution of each process parameter on tribological characteristics has been evaluated by ANOVA. The results reveal that burnishing force has contributed the highest with 39.16% on wear rate, 52.60% on CoF and 50.87% on interfacial temperature. The SEM images revealed wear phenomenons such as oxidation, plastic deformation. Further, the tribological characteristics at unknown test cases have been estimated by ANFIS technique. The model generated the results with an accuracy of 98.69%, 93.35% and 96.26% for wear rate, CoF and temperature respectively.