Process parameter analysis on surface roughness and process forces in micro cutting

Titanium alloy is used in medical industries due to its biocompatibility. Requirement of implant’s surface roughness and surface topography depends mainly upon its application. In the present study, application of titanium alloy is considered as femoral knee joint implant. The capability of magnetic field assisted finishing (MFAF) process and the polishing tool to provide implant worthy surface is analyzed here. In MFAF process, magnetorheological fluid mixed with abrasive powder in acidic base medium is used as the finishing medium. Characterization of the finished surface is carried out by analyzing 3D surface roughness parameters. The selected 3D surface parameters ( Sa, Spk, Sk and Svk) are considered due to their importance concerning load-bearing articulating surface of knee joint implant. Statistical design of experiment is used for experimental study and subsequently process parameters are optimized. From experimental investigation, the values of Sa, Spk, Sk and Svk are obtained as 11.32 nm, 15.82 nm, 6.51 nm and 41.15 nm, respectively, at optimum process parameter condition. The optimum process parameter values are 901 rpm of the tool, 0.60-mm working gap and 4.30 hrs of finishing time. The obtained values of 3D surface roughness parameters are in the nanometer range and the surface topography will render better wear properties, performance and longer implant life. Further confirmation experiments support the optimized values. The effect of individual process parameter on output responses is also analyzed.

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Mikrofräswerkzeuge mit Schneiden aus cBN*/Micro-cutting tools with cBN cutters

wt Werkstattstechnik online ◽

10.37544/1436-4980-2018-11-12-33 ◽

2018 ◽

Vol 108 (11-12) ◽

pp. 773-777

Author(s):

E. Uhlmann ◽

J. Polte ◽

M. Polte ◽

Y. Kuche ◽

H. Wiesner

Keyword(s):

Surface Roughness ◽

Cubic Boron Nitride ◽

Cutting Tools ◽

High Strength ◽

Hardened Steel ◽

Micro Milling ◽

Geometric Accuracy ◽

Micro Cutting ◽

Core Technology ◽

Milling Tools

Die Mikrozerspanung ist eine Kerntechnologie bei der Fertigung von Mikrospritzgussformen. Die hohen Ansprüche an die geometrische Genauigkeit und Oberflächenrauheit erfordern den Einsatz hochfester Werkstoffe. Jedoch unterliegen aktuelle Fräswerkzeuge bei der Mikrozerspanung einem hohen Verschleiß. Einen Lösungsansatz bietet der erfolgreich in der Makrozerspanung eingesetzte Schneidstoff kubisch-kristallines Bornitrid (cBN). Ziel der Untersuchungen war es daher, detaillierte Informationen zur Bearbeitung von gehärtetem Stahl mit cBN-Mikrofräswerkzeugen bereitstellen zu können.   Micro-cutting is a core technology for producing micro-injection moulds. High demands on geometric accuracy and surface roughness require high-strength materials. However, current milling tools for micro-cutting suffer from excessiv tool wear. A solution is offered by cutting materials based on cubic Boron Nitride (cBN), which have been used successfully in macro-machining. This article contains detailed information on the machining of hardened steel with micro-milling tools and cutting edges made of cBN.

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Research on ELID Grinding Mechanism and Process Parameter Optimization of Aluminum-Based Diamond Composites for Electronic Packaging

Science and Engineering of Composite Materials ◽

10.1515/secm-2019-0035 ◽

2019 ◽

Vol 26 (1) ◽

pp. 550-562

Author(s):

Jialiang Guan ◽

Longyue Zhang ◽

Shujun Liu ◽

Yang Yang

Keyword(s):

Surface Roughness ◽

Duty Cycle ◽

Electronic Packaging ◽

Process Parameter ◽

Combination Method ◽

Grinding Wheel ◽

Diamond Composite ◽

Linear Speed ◽

Elid Grinding ◽

Grinding Mechanism

AbstractAiming at the problem of poor processing performance and difficult processing in the process of aluminum-based diamond composites for electronic packaging, this paper uses electrolytic in-process dressing (ELID) grinding technology to grind the aluminum-based diamond composites. The quadratic orthogonal rotation combination method was used to investigate the influence law and degree of grinding depth, grinding wheel linear velocity, duty cycle and electrolysis current on surface roughness. The ELID grinding optimization process parameters of aluminum-based diamond composites obtained by LINGO software are: grinding depth 9.3μm, grinding wheel linear speed 36m/s, duty cycle 63.7%, electrolysis current 11.5A. The surface of the aluminum-based diamond composite with a surface roughness of 125 nm was machined by this optimized process parameter combination.

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Investigation on Mechanism of Ultra-Smoothed Surface with a Micro Slot on the Flank Face in Micro Cutting

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.651-653.764 ◽

2014 ◽

Vol 651-653 ◽

pp. 764-767

Author(s):

Tao Zhang ◽

Hou Jun Qi ◽

Gen Li

Keyword(s):

Surface Roughness ◽

Chip Thickness ◽

Cutting Edge ◽

Back Side ◽

Uncut Chip Thickness ◽

Micro Cutting ◽

Cutting Edge Radius ◽

Edge Radius ◽

Flank Face ◽

Side Flow

Micro cutting is a promising manufacturing method to obtain good surface integrity. Surface roughness shows size effect when the uncut chip thickness is smaller than the cutting edge radius. A special micro slot on the flank face of cutting tools was manufactured with discharge. Two groups of micro orthogonal cutting were conducted. The surface roughness of machined surface was measured and compared to each other. The results show that surface roughness decreases first and then increases with the ratio of uncut chip thickness to cutting edge radius. The surface machined with micro slot is better than that of without micro slot due to the micro slot restrain the back side flow of work piece based on the finite element model.

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