Required Surface Finish Research Articles

Experimental Investigation for the Prediction of Surface Roughness Height Parameters in Abrasive Water Jet Cutting of Kevlar/epoxy Composites

The main objective of the research was to study the influence of the abrasive water jet cutting (AWJC) parameters on the surface roughness parameters Rz1max and Rt, obtained when processing Kevlar fiber-reinforced polymers (KFRP). For this purpose, a full factorial experimental program was designed and roughness evaluations were carried out in two different zones of the cut slot. In this way, it was possible to test the statistical significance of the input parameters effects and characterize both these regions, by means of prediction models proposed for each roughness parameter. Finally, response surfaces and level curves were represented to facilitate the selection of proper factors combination to achieve surface finish requirements.

Vibration modelling analysis of defective parallel robots as machine tools for aerospace parts machining

The strict machining accuracy and surface finish requirements of manufactured products for aerospace parts make it particularly crucial to analyse the vibration performance of parallel robots as machining tools, which directly affects both of these factors. In this paper, a vibration modelling analysis for parallel robots with fewer-DOFs called defective parallel robots is presented, and the effects of four vibration models are also studied. The traditional spring-damping or elastic vibration models of two systems are presented, and the corresponding uncertain vibration systems are developed by considering the effects of gravity and the uncertain joint clearances. Taking a drilling defective parallel robot as an application example, four vibration models are derived, and the differences in natural frequency and vibration response are explored in numerical and experiment comparisons. The results shows that an uncertain system with six DOFs is closer to the experimental result (approximately 75.49%) than an elastic system (approximately 62.39%), which means that the accuracy has increased by 13.1%. The results of this paper reveal some of the reasons for the performance errors of the different vibration models for defective parallel robots, and the findings of this paper can provide a reference for the simplification and optimization of theoretical vibration models that ignore secondary factors.

Design and Analysis of Fixed-Segment Carrier at Carbon Thrust Bearing

Abstract: This thesis work aimed to provide a design and analysis of fixed segment carrier at carbon thrust bearing. With increased the bearing efficiency and reduced the frictional loss and wear resistance. Thrust bearings plays vital role in submersible pumps. Thrust bearings are fixed bottom of the submersible pumps so total thrust or axial load acting on the thrust collar. Thrust collar are manufacturing with resin mixed carbon and casting material and the segments are manufacturing with casting material and stainless steel material. Two types of materials combines to manufacture the segment carrier. The materials hardness and density properties are different from on materials to another material. If suddenly power cut is happen the total load acting on thrust collar. The collar under heavy load carbon surface and segment carrier surface are scratched or damaged the carbon surface. This type of damages are affecting submersible pump. Submersible pumps are fixed with maximum 900 feet under the boar well but this damages are happen we spend more money to lifting the pump from well and also time is wasted. Segment carrier segment surface and thrust pad surface in between micron level film thickness. If the loose segment carrier the loose segment will tilt under the load and vibration of pump. The thrust collar surface is scratched with thrust collar is not rotate because the thrust collar is fitted with rotating shaft with key way. In this study the segment carrier were made with same materials and the hardness of the materials is same and making process are compared to normal bearing were reduced. The segment carrier is made with stainless steel 410 material. The materials are bought a rod or using pattern with investment casting. After the materials is after completing machining process will goes to hardening and materials surface will go to grinding process. The segment surfaces are grinded and achieve the required surface finish. The surface finish techniques are available no of methods. Triondur coating system is more effective than other process. The grinded segment carrier surfaces are goes to next process of lapping. Here the surface is lapped and get required level of surface roughness. In this process the surface roughness is get required level. Because the lapping coating ratio is high the material removal and surface roughness is get more level like 0.2 micron. The diamond powder coating using 100 CRT is lapping process to achieve the required surface finish. The main purpose of the study is to reduce the bearing damages and frictional loss and wear loss and pump damages. And increase the pump life and reduce the raw materials usage

Evaluating and comparing secondary machining characteristics of wrought and additive manufactured 316L stainless steel

This paper is based on evaluating, analysing and comparing the secondary machining characteristics of wrought and additive manufactured 316L Stainless Steel. This paper is an attempt to determine the process efficiency and evaluate the machinability factors which effect the service life. Stainless steel is a historic iron carbon alloy reputed for its high corrosive resistance and extensive application base. Threading, tapping, reaming and knurling are the most common secondary machining operations after a primary machining operation to achieve a required surface finish and form. As threading plays a significant role in fastening two components together. Threading is selected as a secondary machining operation in this paper. The research methodology consists of conducting threading operation on a hollow cylinder of 50 mm diameter using a lathe. Threads are cut into the workpiece using variable cutting parameters such as spindle speed; 90 and 180 rpm and coolant condition; on/off. Thread pitch which is also the feed rate (1 mm/rev) and Depth of Cut (0.3 mm) remains constant for all the trails. Statistical data are collected and analysed by qualitative and quantitative evaluation. The outputs under consideration to evaluate the machinability includes the cutting forces, thread profile accuracy (pitch) and tool wear. It has been observed that the cutting force and the tool wear was predominantly high for SLM compared to wrought. The paper concludes to convey the point that wrought components has better machinability characteristics than additive manufactured stainless steel.

Multi-objective optimization of electrochemical finishing for attaining the required surface finish and geometric accuracy in the hole making process

Multi-objective optimization of electrochemical finishing for attaining the required surface finish and geometric accuracy in the hole making process

Prediction of cutting forces using MRA, GMDH and ANN techniques in micro end milling of titanium alloy

Micro End Milling is an specific procedure for manufacturing biomedical, automotive, naval, aerospace and mining parts especially for super alloys. Surface finish is the necessity output parameter after machining these alloys in the said applications. The study of cutting forces is mandatory to know the required surface finish to be generated on the work material. The influence of machining parameters can be investigated by experimental and predicted results that are very useful for the practitioner engineers inorder to evaluate. In this manuscript, experimental investigation of cutting forces was done and a comparison of the modelling methods - multiple regression analysis (MRA), Group method data handling (GMDH) and Artificial Neural Network (ANN) were presented. In the manuscript, the impact of input factors in machining of Ti-6Al-4 V (Grade-5) titanium alloy using uncoated tungsten carbide tools was studied on cutting forces. From the experimental interpretations, it is found that while increasing machining input parameters cutting forces on workpiece subsequently increases. After the adherences of experiments, experimental values are in good agreement with the accuracy of neural network prediction.

Experimental Investigation on Part Quality and Dust Emission during Minimum Quantity Lubricated (MQL) Edge Finishing of Granite.

Edge-finishing of granites by grinding is a process frequently used in the granite processing industry to generate the final desired shape and edge quality of products. However, this process releases significant amounts of fine and ultrafine particles (FPs and UFPs) containing crystalline silica. When inhaled, this dust can cause silicosis disease and threaten the health and safety of workers. The purpose of this study is to optimize the process by decreasing the concentrations of dust generated while also maintaining the required surface finish. Experimental tests were planned and performed on granite samples using a full factorial design. Two cutting tool edge shapes were studied (chamfer and concave) using G150 and G600 grit size tools, at various spindle speeds (1500, 2500, 3500 rpm), feed rates (500, 1000, 1500 mm/min) and lubrication flow rates (20, 40, 60 mL/min). The findings show that the particle emissions as well as the surface finish depend on the tool shape, its grit size, and the machining and lubrication parameters used. Higher MQL flow rates led to better finished surface quality and lower concentrations of fine dust. Polishing with flood lubrication reduces the maximum number concentration of FPs corresponding to particles smaller than 1 µm diameter by about 85% as compared to dry polishing and produced the best surface finish. Polishing with lubrication in MQL mode at 60 mL/min led to the production of part with Ra-value comparable with that obtained in flood lubrication condition.

Crystalline Phase Changes due to High-Speed Projectiles Impact on 304L Steel

High yield 304L steel is well known for its employment in manufacturing. The quenched and tempered low-carbon alloy has a minimum yield strength of 40-50 ksi. Also, 304L offers good corrosion resistance and weldability. Traces of Chromium and Nickel in 304L give it the desired corrosion resistance properties. So, it is an ideal candidate for pressure vessels and the petrochemical industry applications. The physical characteristics and molecular structure of 304L steel are also well known; however, little is known about the high-velocity impact on this metal alloy’s crystalline structure and material phase changes. The effects of high-speed velocity impact on the crystalline structure and material phase changes due to impacts are studied herein experimentally. The high-speed impact on the crystalline structure’s inevitable phase change is examined, let alone the atomic reorganization resulting from the impact on the 304L steel. The effects of an impact on the crystalline structure are assessed by impacting 304L steel plates (15.4 x 15.4 x1.27 cm) with Lexan projectiles. A two-stage light gas gun accelerates these projectiles to a velocity of 6.70 km/s at the point of the impact. The impacted plates’ surfaces are prepared for the Electron Back Scatter Diffraction (EBSD) microscope inspection. Nine regions on each impacted plate area are examined and analyzed. Each part (90x90) square microns were cut off the test samples, keeping with the required surface finish standards. These regions are selected from the area immediately under the impact crater to locations not physically affected by the impact. Observations of collected EBSD images show that the predominant phase is Body-Centered Cubic (BCC); Face-Centered Cubic (FCC) and Hexagonal-Close-Packed (HCP) phases are also indexed. Since these crystalline structures are the most expected lattice formations, the samples are post-impact examined for molecular structure allocation changes. The results were then tabulated according to the region’s relative impact crater. Previous research, A36 steel results show that post-impact inspection of HCP phase chage, in iron specifically, is completely and rapidly reversible during impact. However, in this study, traces of HCP were found at some locations in all post-impact stages. This study also indicates that the BCC crystalline structure remained the dominant phase structure after impact, and it is valid with all test samples and all levels of shock loading. High pressure and the temperature quickly affect the target material at 6.70 km/sec velocity. The damage zone develops within 5 microseconds at this velocity due to impacting momentum

Multi Objective Optimization Of Burnishing To Eliminate Heat Treatment In Reamer Shank Manufacturing By Using Taguchi Coupled Principal Component Analysis (PCA)

ABSTRACT Burnishing is a well-known cold working technique for improving the surface integrity. It is cost-efficient and effective technique for enhancing surface finish as well as hardness. The use of burnishing to replace current heat treatment including grinding process on the reamer shank is offered as a unique strategy for reamer shank processing. This change in processing reduces cycle time and resources while also conserves energy required for processing during heat treatment and grinding. In this work, principal component analysis (PCA) is coupled with Taguchi optimisation technique to deal with multi-response problem to determine optimum parameter values of burnishing process to attain required surface finish and hardness in order to fulfill all functional requirements of shank. Test outcomes are convincing and show that suggested technique has ability to substitute current heat treatment along with grinding operation for reamer processing.

Surface finishing and tool wear in single point diamond turning of chemical vapour deposited tungsten carbide hard coatings

Precision-engineered components which operate in demanding conditions often require the application of hard coatings such as tungsten carbide (WC) to improve their functional properties. Following the coating deposition process, a surface finishing or machining operation is often required to correct the sizing or achieve adherence to geometrical tolerancing and surface finish requirements. Single point diamond turning (SPDT) is a widely used ultraprecision machining technique for the fabrication of high-end engineering components made up of ductile materials, making it a desirable technique as a post-coating machining or finishing process. In this study the machinability of hard CVD W/WC coatings with a hardness of 1120 ± 15 HV and a thickness of 100 μm using SPDT was investigated. Here we report the results of axial and transverse turning using a cutting speed of 600 rpm and feed rates of 1 and 5 μm respectively. Experimental results show that an Ra of 0.2 μm is achieved with a diamond tool having a 0.5 mm nose radius. Significant tool wear was observed at the rake/flank edge of the diamond tool due to the coating's hardness. Surface and cross-sectional analysis of the samples' machined areas revealed presence of adhesive and abrasive wear. The occurrence of material pile-up due to tool loading on the surface of the coating was investigated through the indentation technique which demonstrated the occurrence of material deformation contributing to the overall surface roughness.

Machining of Additive Manufactured Metal Alloys

Additive Manufacturing of metal alloys offers unique advantages for producing net-shape components of complex geometries with very little waste of material. Nevertheless, machining operations may be needed on functional surfaces to get the required surface finish and geometrical tolerances. This poses challenging issues since the microstructural features characterizing the AM alloys are drastically different from those of the wrought alloys of the same chemical composition, which, in turn, may affect the mechanical and machining response to a great extent. This paper shows that both the machined surface integrity and tool wear are greatly affected by the microstructural features induced by the previous AM process as well as by the build-up orientation.

Effect of annealing temperature on the magnetic properties and finishing efficiency of mechanically alloyed magnetic abrasives

In magnetic abrasive finishing (MAF) process, magnetic abrasives (MAs) act as a multipoint cutting tool that plays an important role in achieving the required surface finish of the workpiece. There are mainly two types of magnetic abrasives, bonded magnetic abrasives (BMAs) and unbounded magnetic abrasives (UMAs). BMAs are found to give better finishing capabilities than UMAs. Most of the previous research studies have applied the sintering technique for bonding abrasive particles with ferromagnetic particles. In this study, mechanical alloying technique, capable of producing a more homogeneous mixture and requiring lesser temperature for its preparation, is applied. The effect of annealing temperature on the magnetic properties and finishing efficiency is evaluated in finishing the internal surface of a brass tube. It has been found that MAs annealed at 950 °C give superior magnetic properties while MAs annealed at 1050 °C give superior finishing efficiency which improved the surface finish by 54.87% in just 10 min of finishing time. The minimum average surface roughness of the workpiece achieved is 0.51 µm in 60 min of finishing time. The working principle, cutting forces and the cutting mechanism has been represented by schematic diagrams for clear understanding.

Machining Character Analysis of Coated and Uncoated End Mill on Heat Treated C45 Steel

Abstract: Machining operations are used to produce shapes or surface characteristics for a product. Some common conventional machining operations are turning, boring, drilling, reaming, milling, and tapping. Conditions for machining operations were chosen based on geometry and surface finish requirements rather than profit when costs were comparatively low on labor, resource, machines, and tools. However, nowadays, many researchers proposed optimizing machining parameters to maximize profit when using expensive modern machine tools. The purpose of machining operations is to make specific shapes or surface characteristics for a product. Conditions for machining operations were traditionally selected based on geometry and surface finish requirements. This study was investigated the parameter optimization of end milling operation various parameter and coated tools and ordinary tool with heat treated C45 steel with single objective function criteria based on the Taguchi orthogonal array with the Taguchi design. Comparison of coated and uncoated end mill process of heat-treated C-45 steel fine Ra is obtained with coated tool. Kerf width almost equal of both tools it did not show any major difference Optimum level and ANOVA were calculated for both tools. Keywords: Ra, PVD coated, Heat treatment, End mill

A novel wiper insert design and an experimental investigation to compare its performance in face milling

ABSTRACT Machining at higher cutting parameters is required to improve productivity. However, in most metal cutting applications, the surface finish requirement limits the parameters at which the tools can be operated. Therefore, tools with wiper facets are used to improve surface integrity. But the length of the facet limits the parameters at which the tool can be operated. Hence, this paper reports a novel wiper milling insert design (convex wiper edge on the rake side) that can improve the surface finish even at a high feed and depth-of-cut. The insert was manufactured in tungsten carbide material and the surface finish, machining power, and cutting forces were measured at various feeds and depth-of-cuts in machining cast iron. The study finds that the wiper insert can be used to improve the surface finish by around 35% in all the selected machining parameters. The arithmetical mean roughness (Ra) of wiper insert at 0.4 mm/tooth was better than the roughness values produced by the conventional inserts at 0.1 mm/tooth which gives a productivity improvement of more than four times. The machining dynamics of the conventional and the wiper insert are discussed in detail.

Investigation of vibration in boring operation to improve Machining process to get required surface finish

Boring is a most commonly used lathe machine operation to enlarge the small holes of any structures. When a cantilever and long boring tool is used, it is subjected to optimum static deflections or self-excited vibrations, which reduces the accuracy and surface wrap up of the boring operation. It also causes the tool to wear out and become damaged. Boring frequently necessitates the use of a long and slender boring tool to machine inside a hole, and vibrations become strongly correlated with one of the boring tool's fundamental bending modes. There are several methods for reducing vibrations; however, implementing the most efficient and stable methods necessitates extensive knowledge of the dynamic characteristics of the tooling system. Moreover, the functionality between the boring tool as well as the clamping house has a significant impact on the clamped boring tool's dynamic properties. This paper examines the behavior of a boring tool under various overhang lengths that are frequently used in the machining process.

Performance Investigation of Cryo-treated End Mill on the Mechanical and in vitro behavior of Hybrid-lubri-coolant-milled Ti-6Al-4V alloy

Global demographic trends have signaled a growing need for biomedical implants such as artificial hips, dental implants, spine screws, coronary stents, and heart pacemakers. The reliability of a manufactured implant can be primarily ensured in terms of its surface integrity, dimensional accuracy, and biocompatibility. In the case of subtractive manufacturing of an implant, the required surface finish and complex geometrical features take the machining to a whole new level. However, the machining of mostly metallic biomaterials such as titanium and its alloys has always been challenged by their poor machinability. In this regard, the latest research has reported the outperformance of cryogenically treated non-coated and coated cutting tools and hybrid cooling environments, which resulted in a noteworthy improvement of machinability and biocompatibility of difficult-to-machine biocompatible materials. Therefore, the present research aimed to enhance the surface integrity and in vitro biocompatibility of Ti-6Al-4V alloy by using AlTiN coated solid carbide end mill in untreated and cryogenically treated condition with wet (using traditional cutting fluid as coolant), cryo (using liquid nitrogen as coolant), and hybrid-lubri-coolant (using a combination of cutting fluid and liquid nitrogen as coolant). The experimental findings were analyzed by RStudio software. The results reported that untreated end mill with cryo-lubri-coolant (C-LC) and cryo-treated end mill with hybrid-lubri-coolant (H-LC) achieved the targeted objectives of this research. However, the cryo-treated end mill with H-LC outperformed the untreated end mill with C-LC and produced better surface characteristics, confirmed by a morphological study of the H-LC-milled surface and cryo-treated end mill. The finding of the in vitro studies confirmed that the H-LC-milled surface exhibited superior biocompatibility and promoted the adhesion, growth, and proliferation of adipose-derived stem cells (ADSCs).

Surface finishing requirements on various internal cylindrical components: A review

Modern technology requires producing of a sustainable product with a high surface accuracy. In applications where the surface quality is highly considerable in various internal cylindrical components requires technology to manufacture an ultrafine surface finish. There is, in general, a probability of inducing errors into products by the traditional finishing processes (such as grinding/honing), which lead to failure. Preferably with some evidence in the main text. Further, the advanced finishing processes are developed, where the finishing forces can be controlled by varying the power output. Instead of a solid abrasive tool, the smart polishing fluid is used, which gets activated under the magnetic fields. In this manuscript, the material removal under different internal surface finishing processes is elaborated, which helps in improving the surface quality of various industrial components. Also, the surface quality produced on various industrial components after traditional as well as advanced finishing processes are discussed.

Effect of machining parameters on turning process of Inconel 718

ABSTRACT Inconel 718 superalloys are known materials with high applicability to components that demand exceptional chemical and mechanical properties at higher working temperatures combined with excellent surface finish requirements. However, due to the lack of in-depth knowledge regarding its machining process, the material is considered a difficult-to-machine material. Therefore, to improve the machining process of the Inconel 718 superalloy, by finding the optimal processing conditions, it was necessary to analyze the influence of the cutting parameters on the workpiece surface quality. In this work, the evaluation of quality indicators was made through the influence analysis of cutting speed, feed, tool, and lubrication parameters. The surface roughness (Ra, Rt), consumed power, vibration, and tool wear indicators were evaluated by following a Taguchi experimental design. To perform the machining process, the tool CNMG120408-M1 coating TS2500 with minimum quantity of lubricant was used. Results have proven that feed rate adjusted to 0.10 mm/rev and the cutting speed of 70 m/min provided the optimal processing results. It was observed that the feed increase led to an increase of all indicators. Consumed power denoted high sensibility concerning the machining parameters, suggesting its potential use in tool wear prediction studies applied for the Inconel 718 machining.

Analysis of temperature and surface finish of Inconel 718 during grinding utilizing different grinding wheels

Nickel-based superalloy Inconel 718 is widely used for aeronautical applications, such as blades and discs of aircraft engines, and therefore is generally submitted to a grinding process in order to meet the required surface finish and dimensional accuracy. However, the mechanical and thermal properties of Inconel 718 make it a material with low machinability (difficult-to-machine material). Therefore, the proper selection of abrasives is of high importance, when aiming to improve process efficiency. White aluminum oxide (WA) and green silicon carbide (GC) abrasives are the most common conventional abrasives employed in the grinding of nickel-based superalloys, and their different properties can be decisive when it comes to the success of the process. In this sense, this work sought to evaluate the performance of two conventional abrasives (WA and GC) in the grinding of Inconel 718 with cutting fluid applied with a conventional technique. Five different cutting conditions were tested. Surface finish (Ra and Rz parameters) and cutting region temperature were used to assess grinding performance. The results showed that, compared to WA, grinding with the GC wheel reduced roughness in 14% and 19% for Ra and Rz, respectively, even though this produced higher cutting region temperatures (55% higher in general). However, for more severe cutting conditions (e.g., higher values of radial depth of cut), the characteristic wear mechanism of the GC wheel further increases cutting region temperature, resulting in surface finish deterioration.

Investigation of the Effect of Wire Electrical Discharge Machining on the Fracture Toughness of Aluminum-Boron Carbide Composite

Aluminum metal matrix composites reinforced by ceramic particles have a wide acceptance in engineering applications due to their mechanical and physical properties. One of the major challenges in machining these composites by the conventional machining operations is the presence of the abrasive particles, which affects the tool life and the required surface finish. Electro discharge machining process is widely used instead of conventional methods to overcome these challenges. Therefore, it is essential to study the influence of the electro-discharge machining on its fracture toughness, as it is the most important structural integrity indicator in the wide range applications of the studied composites. In this work, all samples were prepared by the stir casting method with using a squeezing pressure during the solidification. Samples were reinforced by (0, 2, 4, and 6wt %) of B4C particles with a size of 0.387μm. The fracture toughness studied were based on the stress intensity factor, determined experimentally by using compact tensile test and numerically using the finite element method. The fracture toughness improvement was recorded for the samples containing 4wt% of B4C.