Cutting speed influence on surface integrity of hard turned bainite steel

The superalloy parts in the aeronautical field demand high reliability, which is largely related to surface integrity. Surface integrity generally includes three parameters, such as geometric parameter, mechanical parameter and metallurgical parameter. The paper presents the influence of cutting speed on surface plastic deformation and white layer formation through orthogonal milling of FGH95 superally material. The influence of cutting speed on grain refinement of machined surface is also investigated. It is found that cutting speed has significantly effect on the surface metallurgical characteristic microstructure. The increasing of cutting speed creates severer plastic deformation. Surface plastic shear strain increases with the increasing of cutting speed, while the depth of plastic deformation decreases on contrary. White layer thickness is increased with the increasing of cutting speed. Through statistical analysis for grains number, it can be drawn that the higher the cutting speed, the more serious grains refinement.

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Surface integrity in laser-assisted machining of Ti6Al4V

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406220978255 ◽

2020 ◽

pp. 095440622097825

Author(s):

O Kalantari ◽

MM Fallah ◽

F Jafarian ◽

SR Hamzeloo

Keyword(s):

Surface Roughness ◽

Grain Size ◽

Surface Integrity ◽

Cutting Tool ◽

Cutting Temperature ◽

Cutting Speed ◽

Laser Source ◽

Depth Of Cut ◽

Thermal Source ◽

Laser Assisted Machining

In laser-assisted machining (LAM), the laser source is focused on the workpiece as a thermal source and locally increases the workpiece temperature and makes the material soft ahead of the cutting tool so using this method, the machining forces are reduced, which causes improving the surface quality and cutting tool life. Machinability of advanced hard materials is significantly low and conventional methods do not work effectively. Therefore, utilizing an advanced method is inevitable. The product life and performance of complex parts of the leading industry depends on surface integrity. In this work, the surface integrity features including microhardness, grain size and surface roughness (Ra) and also the maximum cutting temperature were investigated experimentally in LAM of Ti-6Al-4V. According to the results, cutting speed has inverse effect on the effectiveness of LAM process because with increasing speed (15 to 63 m/min), temperature decreases (524 °C to 359 °C) and surface roughness increases (0.57 to 0.71 μm). Enhancing depth of cut and feed has direct effect on the process temperature, grain size, microhardness and surface roughness.

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Investigations on surface roughness and microhardness of turned AM alloy

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406220976162 ◽

2020 ◽

pp. 095440622097616

Author(s):

Sunil Dutta ◽

NSK Reddy

Keyword(s):

Surface Roughness ◽

Surface Integrity ◽

Cutting Speed ◽

Depth Of Cut ◽

Feed Speed ◽

Average Roughness ◽

Study Results ◽

Superior Surface ◽

Input Variables ◽

Response Variables

Manufacturers in different sectors look for materials exhibiting good mechanical properties, high machinability, and superior surface integrity. The machinability of Mg alloys is one of the vital aspects which requires an exhaustive survey during their selection for different applications. The study examines the surface integrity of a fabricated AM alloy (Mg alloy with 7 wt%Al-0.9 wt%Mn) through dry turning. During the experiments, the input variables of turning viz. cutting speed( v), depth of cut (DOC), and feed( f) is altered and applied to the workpiece. The data obtained for the two response variables viz. surface roughness and microhardness accentuate the maximum influence of feed, followed by DOC and speed. For validation a two-stage methodology was adopted; In the first stage, the validation was done with the help of Analysis of variance (ANOVA); the results show the % contribution of feed, speed, and DOC on average roughness is 66.94%, 5.91%, and 27.23% and on microhardness is 47%, 8.3%, and 44.57%, respectively. Subsequently, in the second stage, the surface plots are drawn for both the response variables to ascertain the ANOVA outcomes; the shape of the plots corroborates the experimental and ANOVA results. The study results provide vital insights for parameter selection to get improved results on surface roughness and microhardness during machining of AM alloy.

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Effect of Machining Parameters and MQL Liquids on Surface Integrity of High Speed Drilling Ti-6Al-4V

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.447-448.816 ◽

2010 ◽

Vol 447-448 ◽

pp. 816-820 ◽

Cited By ~ 3

Author(s):

Erween Abdul Rahim ◽

Hiroyuki Sasahara

Keyword(s):

Surface Roughness ◽

Palm Oil ◽

Surface Integrity ◽

High Speed ◽

Cutting Speed ◽

Machining Parameters ◽

Machined Surface ◽

Subsurface Deformation ◽

High Speed Drilling ◽

Coated Carbide

Surface integrity is particularly important for the aerospace industry components in order to permit longer service life and maximized its reliability. This present work compares the performance of palm oil and synthetic ester on surface roughness, surface defect, microhardness and subsurface deformation when high speed drilling of Ti-6Al-4V under MQL condition. The drilling tests were conducted with AlTiN coated carbide tool. The surface roughness decreased with increasing in cutting speed and thicker subsurface deformation was formed underneath the machined surface. Grooves, cavities, pit holes, microcracks and material smearing were the dominant surface damages thus deteriorated the machined surface. For both lubricants, the machined surface experienced from thermal softening and work hardening effect thus gave a variation in microhardness values. The results indicated the substantial benefit of MQL by palm oil on surface integrity.

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The Effect of Tool Edge Geometry on Tool Performance and Surface Integrity in Turning Ti-6Al-4V Alloys

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.264-265.1211 ◽

2011 ◽

Vol 264-265 ◽

pp. 1211-1221 ◽

Cited By ~ 4

Author(s):

Yanuar Burhanuddin ◽

Che Hassan Che Haron ◽

Jaharah A. Ghani

Keyword(s):

Tool Life ◽

Surface Integrity ◽

Feed Rate ◽

Cutting Speed ◽

Optical Microscope ◽

Edge Geometry ◽

Tool Performance ◽

Tool Edge ◽

Structural Deformations ◽

Notch Wear

This paper focuses on the influence of cutting tool edge geometry, cutting speed and feed rate on the tool performance and workpiece’s surface integrity in dry turning of Ti-6Al-4V alloy using PCBN inserts. The parameters evaluated are tool life, wear rate, wear mechanisms, surface roughness and subsurface microstructure alterations. The rate of wear growth of the insert was assessed by progressive flank wear using optical microscope by taking photographs after certain length of cut. The wear mechanism at the end of tool life was investigated in detail using scanning electron microscope (SEM) and EDAX analysis. The results show, by increasing the cutting speed and feed rate resulted in tool life reduction. Cutting with honed edge insert at cutting speed of 180 m/min has shown very little wear, even after 20 min of cutting. The honed insert proved less sensitive to increases in feed rate than the chamfered insert. In general the honed insert showed a significant improvement in tool life. All inserts failed due to attrition wear and adhesion. No flank notch wear was observed, but some crater wear occurred at the chamfer land. Microstructure alteration was not found when machining using the different edge geometry. In these trials, the subsurface micro structural deformations in the direction of cutting were deformed grain boundaries and elongation of grains. Chip smearing and debris on the surface was also found.

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RSM Based Investigations on the Effects of Cutting Parameters on Surface Integrity during Cryogenic Hard Turning of AISI 52100

Journal for Manufacturing Science and Production ◽

10.1515/jmsp-2015-0009 ◽

2015 ◽

Vol 15 (3) ◽

pp. 309-318 ◽

Cited By ~ 1

Author(s):

Suha K. Shihab ◽

Zahid A. Khan ◽

Arshad Noor Siddiquee

Keyword(s):

Surface Integrity ◽

Feed Rate ◽

Hard Turning ◽

Desirability Function ◽

Cutting Speed ◽

Cutting Parameters ◽

Depth Of Cut ◽

Machined Surface ◽

Aisi 52100 ◽

Model Equations

AbstractEffect of cryogenic hard turning parameters (cutting speed, feed rate, and depth of cut) on surface roughness (Ra) and micro-hardness (µH) that constitute surface integrity (SI) of the machined surface of alloy steel AISI 52100 is investigated. Multilayer hard surface coated (TiN/TiCN/Al2O3/TiN) insert on CNC lathe is used for turning under different cutting parameters settings. RSM based Central composite design (CCD) of experiment is used to collect data for Ra and µH. Validity of assumptions related to the collected data is checked through several diagnostic tests. The analysis of variance (ANOVA) is used to determine main and interaction effects. Relationship between the variables is established using quadratic regression model. Both Ra and µH are influenced principally by the cutting speed and the feed rate. Model equations are found to predict accurate values of Ra and µH. Finally, desirability function approach for multiple response optimization is used to produce optimum SI.

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A Study of Surface Integrity when Machining Refractory Titanium Alloys

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.83-86.1059 ◽

2009 ◽

Vol 83-86 ◽

pp. 1059-1068 ◽

Cited By ~ 1

Author(s):

Armansyah Ginting ◽

Mohammed Nouari ◽

Nadhir Lebaal

Keyword(s):

Surface Roughness ◽

Titanium Alloys ◽

Surface Integrity ◽

Bulk Material ◽

Cutting Speed ◽

Cutting Condition ◽

Feed Speed ◽

Machined Surface ◽

Feed Mark ◽

Coated Carbide

In this paper, the surface integrity is studied when machining the aeronautical titanium alloys. Surface roughness, lay, defects, microhardness and microstructure alterations are studied. The result of surface roughness judges that the CVD-coated carbide fails to produce better Ra value than the uncoated. Lay is characterized by cutting speed and feed speed directions. Feed mark, tearing surface, chip layer formation as built up layer (BUL), and deposited microchip are the defects. Microhardness is altered down to 350 microns beneath the machined surface. The first 50 microns is the soft sub-surface caused by thermal softening in ageing process. Microstructure alteration is observed in this sub-surface. Down to 200 microns is the hard sub-surface caused by the cyclic internal work hardening and then it is gradually decreasing to the bulk material hardness. It is concluded that dry machining titanium alloy is possible using uncoated carbide with cutting condition limited to finish or semi-finish for minimizing surface integrity alteration.

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Surface Integrity of Magnesum-Calcium Orthopedic Biomaterial Procesed by Dry High-Speed Face Milling

ASME 2010 5th Frontiers in Biomedical Devices Conference and Exhibition ◽

10.1115/biomed2010-32062 ◽

2010 ◽

Author(s):

M. Salahshoor ◽

Y. B. Guo

Keyword(s):

Surface Integrity ◽

Human Body ◽

High Speed ◽

Mechanical Load ◽

Cutting Speed ◽

Polycrystalline Diamond ◽

Orthopedic Implants ◽

Face Milling ◽

Depth Of Cut ◽

Machining Parameter

Biodegradable magnesium-calcium (Mg-Ca) implants have the ability to gradually dissolve and absorb into the human body after implantation. The critical issue that hinders the application of Mg-Ca implants is its poor corrosion resistance to human body fluids. A promising approach to tackle this issue is tailoring the surface integrity characteristics of the orthopedic implants to get an appropriate corrosion kinetic. High speed face milling of biodegradable Mg-Ca alloy is used in this study as a possible way to achieve that goal. Polycrystalline diamond inserts are used to avoid material adhesion and likely fire hazards. All the cutting tests are performed without using coolant to keep the manufacturing process ecological. High cutting speed of 40 m/s and 200 μm depth of cut are applied in a broad range of feed values to cover finish and rough cutting regimes. The effect of feed as a key machining parameter which defines the amount and duration of thermo-mechanical load and ultimately provides higher chances for surface integrity changes are investigated.

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