scholarly journals Anti-Friction and Anti-Wear Mechanisms of Micro Textures and Optimal Area Proportion in the End Milling of Ti6Al4V Alloy

2019 ◽  
Vol 3 (4) ◽  
pp. 91 ◽  
Author(s):  
Tong ◽  
Liu ◽  
Yu
Keyword(s):  
Wear Mechanisms ◽  
End Milling ◽  
Hard Metal ◽  
Starting Point ◽  
Milling Tool ◽  
Low Efficiency ◽  
Optimal Area ◽  
Metal Tools ◽  
Wear Tests ◽  
Friction And Wear Tests

To solve the problems of low efficiency, poor surface quality, and short tool life in the milling of titanium alloys, this study took the micro-textured ball-end milling tool as a starting point and established a platform for friction and wear tests. Based on a new method of external friction theory, the anti-friction and anti-wear mechanisms of the micro-textured tool were analyzed. According to these mechanisms, the optimal area proportion of the micro textures in the contact area between the chip and tool was theoretically investigated considering the milling force, and the proportion was verified experimentally. This work provides a reference for improving the cutting performance of hard metal tools.

scholarly journals Influence of Selected Model Parameters on the Electromagnetic Levitation Melting Efficiency

2021 ◽  
Vol 11 (9) ◽  
pp. 3827
Author(s):  
Blazej Nycz ◽  
Lukasz Malinski ◽  
Roman Przylucki
Keyword(s):  
Electromagnetic Levitation ◽  
Optimization Methods ◽  
Calculation Model ◽  
Model Parameters ◽  
Starting Point ◽  
Low Efficiency ◽  
The Relationship ◽  
Reactive Metals ◽  
Electromagnetic Levitation Melting ◽  
Metal Melting

The article presents the results of multivariate calculations for the levitation metal melting system. The research had two main goals. The first goal of the multivariate calculations was to find the relationship between the basic electrical and geometric parameters of the selected calculation model and the maximum electromagnetic buoyancy force and the maximum power dissipated in the charge. The second goal was to find quasi-optimal conditions for levitation. The choice of the model with the highest melting efficiency is very important because electromagnetic levitation is essentially a low-efficiency process. Despite the low efficiency of this method, it is worth dealing with it because is one of the few methods that allow melting and obtaining alloys of refractory reactive metals. The research was limited to the analysis of the electromagnetic field modeled three-dimensionally. From among of 245 variants considered in the article, the most promising one was selected characterized by the highest efficiency. This variant will be a starting point for further work with the use of optimization methods.

Prediction of Burr Formation in Fabricating MEMS Components by Micro End Milling

2009 ◽  
Vol 74 ◽  
pp. 247-250 ◽  
Author(s):  
Mohammad Yeakub Ali ◽  
Mohd Aliff Omar ◽  
Khairul Irman Othman ◽  
Wayne N.P. Hung
Keyword(s):  
End Milling ◽  
Cutting Speed ◽  
304 Stainless Steel ◽  
Burr Formation ◽  
Aisi 304 ◽  
Burr Height ◽  
Milling Parameters ◽  
Milling Tool ◽  
Micro End Milling ◽  
Chip Load

This paper discusses burr formation in micromilling of AISI 304 stainless steel. Chip load, cutting speed and the application of coolant were chosen as the milling parameters. Experiments were conducted using 500 µm diameter tungsten carbide end milling tool. Milling parameters and measured burr height values were analyzed and statistical models were developed for the estimation of burr height. The models showed that the chip load and cutting speed both have direct and interactive contribution to burr formation. When micromachining without coolant, the burr height increases about 40% compared to that of machining with coolant. The optimized values of chip load and cutting speed were found to be 1 µm/tooth and 78 mms-1 respectively. The predicted burr heights were 5-7% larger than that of measured values.

scholarly journals Experimental and Numerical Analysis of High-Speed Internally Cooled Milling

CONVERTER ◽  
2021 ◽  
pp. 748-756
Author(s):  
Ningxia Yin Et al.
Keyword(s):  
High Speed ◽  
End Milling ◽  
Double Helix ◽  
Channel Structure ◽  
Dynamics Simulation ◽  
Thermal Dissipation ◽  
Machined Surface ◽  
Milling Tool ◽  
Internally Cooled ◽  
Cooling Technology

Advanced cooling technology is a crucial measure of thermal dissipation for high-speed end-milling. In order to get an appropriate cooling technology and decrease the negative effects of traditional wet cutting, internally cooled cutting has been paid more and more attention. Because of interrupted cutting and uneven force, there was few application and investigation on internally cooled end-milling. In the paper, the effect of the end-milling tool with different internally cooled channel structure has been researched by experiment and theoretical analysis. The experimental results indicate that the end-milling tool with double helix channels carried out best machined surface quality. And the experiment result was also been analyzed and explained by computational fluid dynamics simulation, which provides a basis for the applying of the high-speed internally cooled end-milling tool.

Tribological behavior of UHMWPE in water lubrication: the effect of molding temperature

2022 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Xincong Zhou ◽  
Chaozhen Yang ◽  
Jian Huang ◽  
Xueshen Liu ◽  
Da Zhong ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Friction Coefficient ◽  
Friction And Wear ◽  
Wear Loss ◽  
Content Type ◽  
Molding Temperature ◽  
Melting Temperatures ◽  
Ultra High Molecular Weight ◽  
Wear Tests ◽  
Friction And Wear Tests

Purpose Ultra-high molecular weight polyethylene (UHMWPE) is adopted in water-lubricated bearings for its excellent performance. This paper aims to investigate the tribological properties of UHMWPE with a molecular weight of 10.2 million (g mol‐1) under different molding temperatures. Design/methodology/approach The UHMWPE samples were prepared by mold pressing under constant pressure and different molding temperatures (140°C, 160°C, 180°C, 200°C, 220°C). The friction and wear tests in water were conducted at the RTEC tribo-tester. Findings The friction coefficient and wear loss decreased first and rose later with the increasing molding temperature. The minimums of the friction coefficient and wear loss were found at the molding temperatures of 200°C. At low melting temperatures, the UHMWPE molecular chains could not unwrap thoroughly, leading to greater abrasive wear. On the other hand, high melting temperatures will cause the UHMWPE molecular chains to break up and decompose. The optimal molding temperatures for UHMWPE were found to be 200°C. Originality/value Findings are of great significance for the design of water-lubricated UHMWPE bearings.

Experimental Investigation of the Effect of the Machine Kinematic Behavior on the Surface Topography and Roughness in High Speed Ball end Milling of the AISI4142 Steel

2021 ◽  
Author(s):  
Sai Lotfi ◽  
Belguith Rami ◽  
Baili Maher ◽  
Desseins Gilles ◽  
Bouzid Wassila
Keyword(s):  
Surface Topography ◽  
High Speed ◽  
End Milling ◽  
Experimental Investigations ◽  
Ball End Milling ◽  
Tool Paths ◽  
Stationary Zone ◽  
Machining Errors ◽  
Kinematic Behavior ◽  
Milling Tool

Abstract The analysis of the surface topography in ball end milling is an objective studied by many researchers, several methods were used and many combinations of cutting conditions and machining errors are considered. In the milling tool paths the trajectories presents a points of changing direction where the tool decelerates before and accelerates after respecting the velocity profiles of the machine. In this paper, we propose experimental investigations of the effect of the kinematic behavior of the machine tool on the surface quality. A poor topography and roughness are remarked on the deceleration and the acceleration zones compared to the stationary zone.

Hydrogen-Induced Wear of Ti–6Al–4V Alloy

2012 ◽  
Vol 476-478 ◽  
pp. 566-569
Author(s):  
Bao Guo Yuan ◽  
Hai Ping Yu ◽  
Ping Li ◽  
Gui Hua Xu ◽  
Chun Feng Li ◽  
...  
Keyword(s):  
Wear Mechanism ◽  
Chemical Element ◽  
Friction And Wear ◽  
Room Temperature ◽  
Sliding Friction ◽  
Wear Properties ◽  
Friction And Wear Properties ◽  
Worn Surface ◽  
Wear Tests ◽  
Friction And Wear Tests

The effects of hydrogen on friction and wear properties of Ti–6Al–4V alloy sliding against GCr15 steel were investigated through dry sliding friction and wear tests in atmosphere at room temperature. Wear mechanism was determined by studying the morphology and chemical element of worn surface using SEM and EDS. Results show that friction coefficient decreases slightly and wear rate increases after hydrogenation. Wear mechanism is discussed.

A HIGHER FIDELITY MODELING OF THE CUTTING EDGE OF BALL-END MILLING TOOL

2011 ◽  
Vol 10 (01) ◽  
pp. 101-108 ◽  
Author(s):  
XIULIN SUI ◽  
IMRE HORVATH ◽  
JIATAI ZHANG ◽  
PING ZHANG
Keyword(s):  
End Milling ◽  
Milling Process ◽  
Cutting Edge ◽  
Ball End Milling ◽  
Machining Conditions ◽  
Milling Tool ◽  
Efficient Planning ◽  
Pilot Implementation ◽  
Physical Changes ◽  
Milling Forces

Ball-end milling tools have been widely used in machining of complex freeform surfaces. The precision and efficiency of ball-end milling process can be improved by an accurate modeling of the tools, the tools' paths and the machining conditions. However, only rough geometric models have been applied so far, which do not consider the machining conditions and the physical changes. To achieve the best results, an accurate modeling of the cutting edge and the physical behavior of the entire cutter is needed. This paper proposes an articulated model that enumerates both the geometric characteristics and the physical effects acting on the cutting edge-segment of a ball-end milling cutter. The model considers the deformations caused by the milling forces, vibration, spindle eccentricity, together with thermal deformation and wear of the cutter. The mathematical description of the behavior has been transferred into a computational model. The pilot implementation has been tested in a practical application. The first findings show that the proposed theoretical model and implementation provide sufficiently precise information about the behavior of the cutter in virtual simulations; hence it can be the basis of a fully fledged and more efficient planning of milling processes.

The tribological performance of engineered micro-surface topography by picosecond laser on PEEK

2019 ◽  
Vol 72 (1) ◽  
pp. 172-179 ◽  
Author(s):  
Meiling Wang
Keyword(s):  
Tribological Properties ◽  
Design Methodology ◽  
Friction And Wear ◽  
Picosecond Laser ◽  
Wear Property ◽  
Content Type ◽  
Friction Curve ◽  
Micro Structures ◽  
Wear Tests ◽  
Friction And Wear Tests

Purpose The purpose of this study is to investigate the effect of engineered micro-structures on the tribological properties of metal-polyetheretherketone (PEEK) surface. Design/methodology/approach Circular dimples with diameters of 25 and 50 µm were designed and manufactured on PEEK plate specimens using picosecond laser. Reciprocating friction and wear tests on a ball-on-flat configuration were performed to evaluate the tribological properties of the designed micro-structures in dry contacts. The loading forces of 0.9 and 3 N were applied. Findings As a result, obvious fluctuations of coefficient of friction curve were observed in tribosystems consisting of non-textured and textured PEEK with circular dimples of 25 µm in diameter. GCr15 ball/textured PEEK plate specimens with circular dimples of 50 µm in diameter revealed a superior friction and wear property. Originality/value Different to the existing studies in which the tribopairs consist of hard bearing couples, this study investigated the tribological properties of the engineered micro-structures on the hard-on-soft bearing couples.

Friction and Wear Reduction of 440C Stainless Steel by Ion Implantation

1983 ◽  
Vol 27 ◽  
Author(s):  
L. E. Pope ◽  
F. G. Yost ◽  
D. M. Follstaedt ◽  
S.T. Picraux ◽  
J. A. Knapp
Keyword(s):  
Stainless Steel ◽  
Surface Layer ◽  
Yield Strength ◽  
Ion Implantation ◽  
Friction And Wear ◽  
No Reduction ◽  
Wear Reduction ◽  
Amorphous Surface ◽  
Wear Tests ◽  
Friction And Wear Tests

ABSTRACTFriction and wear tests on ion-implanted 440C stainless steel discs have been extended to high Hertzian stresses (≤ 3150 MPa). Implantation of 2 × 1015 Ti/mm2 (180–90 keV) and 2 × 1015 C/mm2 (30 keV) into 440C reduces friction (∼40%) and wear (> 80%) for Hertzian stresses as large as 2900 MPa, stresses which significantly exceed the yield strength of 440C (∼1840 MPa). Implantation of 4 × 1015 N/mm2 (50 keV) into 440C reduces friction slightly (∼25%) for Hertzian stresses > 1840 MPa but provides little or no reduction in wear. The amount of Ti remaining in the wear tracks correlates with the reductions in friction and wear. The implantation of Ti and C produces an amorphous surface layer which is believed to reduce friction and wear, whereas N implantation is expected to produce hard nitride particles which probably do not modify the hardness of 440C (KHN = 789) significantly.

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