Micro-dimple pattern process and orthogonal cutting force analysis of elliptical vibration texturing

The formation of serrated chips is an important feature during machining of difficult-to-cut materials, such as titanium alloy, nickel based alloy, and some steels. In this study, Ti6Al4V alloys with equiaxial and acicular martensitic microstructures were adopted to analyze the effects of material structures on the formation of serrated chips in straight line micro orthogonal machining. The martensitic alloy was obtained using highly efficient electropulsing treatment (EPT) followed by water quenching. The results showed that serrated chips could be formed on both Ti6Al4V alloys, however the chip features varied with material microstructures. The number of chip segments per unit length of the alloy with martensite was more than that of the equiaxial alloy due to poor ductility. Besides, the average cutting and thrust forces were about 8.41 and 4.53 N, respectively, for the equiaxed Ti6Al4V alloys, which were consistently lower than those with a martensitic structure. The high cutting force of martensitic alloy is because of the large yield stress required to overcome plastic deformation, and this force is also significantly affected by the orientations of the martensite. Power spectral density (PSD) analyses indicated that the characteristic frequency of cutting force variation of the equiaxed alloy ranged from 100 to 200 Hz, while it ranged from 200 to 400 Hz for workpieces with martensites, which was supposedly due to the formation of serrated chips during the machining process.

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Influence of tool edge form factor and cutting parameters on milling performance

Advances in Mechanical Engineering ◽

10.1177/16878140211009041 ◽

2021 ◽

Vol 13 (4) ◽

pp. 168781402110090

Author(s):

Xuefeng Zhao ◽

Hao Qin ◽

Zhiguo Feng

Keyword(s):

Form Factor ◽

Simulation Model ◽

Cutting Force ◽

Surface Quality ◽

High Speed ◽

Orthogonal Cutting ◽

Cutting Temperature ◽

Tool Edge ◽

Drag Finishing ◽

Edge Preparation

Tool edge preparation can improve the tool life, as well as cutting performance and machined surface quality, meeting the requirements of high-speed and high-efficiency cutting. In general, prepared tool edges could be divided into symmetric or asymmetric edges. In the present study, the cemented carbide tools were initially edge prepared through drag finishing. The simulation model of the carbide cemented tool milling steel was established through Deform software. Effects of edge form factor, spindle speed, feed per tooth, axial, and radial cutting depth on the cutting force, the tool wear, the cutting temperature, and the surface quality were investigated through the orthogonal cutting simulation. The simulated cutting force results were compared to the results obtained from the orthogonal milling experiment through the dynamometer Kistler, which verified the simulation model correctness. The obtained results provided a basis for edge preparation effect along with high-speed and high effective cutting machining comprehension.

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Process parameters influence on cutting force and surface roughness during hybrid laser- and ultrasonic elliptical vibration-assisted machining

Journal of the Brazilian Society of Mechanical Sciences and Engineering ◽

10.1007/s40430-020-02751-2 ◽

2021 ◽

Vol 43 (1) ◽

Author(s):

Mohsen Khajehzadeh ◽

Seyyed Sajjad Ahmadpoor ◽

Omid Rohani Raftar ◽

Mohammad Reza Beyki Sarveolia ◽

Mohammad Reza Razfar

Keyword(s):

Surface Roughness ◽

Cutting Force ◽

Process Parameters ◽

Elliptical Vibration ◽

Ultrasonic Elliptical Vibration

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Preparation and cutting performance of nano-scaled Al2O3-coated micro-textured cutting tool prepared by atomic layer deposition

High Temperature Materials and Processes ◽

10.1515/htmp-2021-0021 ◽

2021 ◽

Vol 40 (1) ◽

pp. 77-86

Author(s):

Siwen Tang ◽

Pengfei Liu ◽

Zhen Su ◽

Yu Lei ◽

Qian Liu ◽

...

Keyword(s):

Friction Coefficient ◽

Atomic Layer Deposition ◽

Cutting Force ◽

Cutting Tool ◽

Orthogonal Cutting ◽

Cutting Tools ◽

Atomic Layer ◽

Cutting Performance ◽

Cutting Test ◽

Layer Deposition

Abstract Al2O3 nano-scaled coating was prepared on micro-textured YT5 cemented carbide cutting tools by atomic layer deposition ALD. The effect of Al2O3 nano-scaled coating, with and without combined action of texture, on the cutting performance was studied by orthogonal cutting test. The results were compared with micro-textured cutting tool and YT5 cutting tool. They show that the micro-texture and nano-scaled Al2O3 coated on the micro-texture both can reduce the cutting force and friction coefficient of the tool, and the tools with nano-scaled Al2O3 coated on the micro-texture are more efficient. Furthermore, the friction coefficient of the 100 nm Al2O3-coated micro-texture tool is relatively low. When the distance of the micro-pits is 0.15 mm, the friction coefficient is lowest among the four kinds of pit textured nanometer coating tools. The friction coefficient is the lowest when the direction of the groove in strip textured nanometer coating tool is perpendicular to the main cutting edge. The main mechanism of the nanometer Al2O3 on the micro-textured tool to reduction in cutting force and the friction coefficient is discussed. These results show that the developed tools effectively decrease the cutting force and friction coefficient of tool–chip interface.

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