scholarly journals Atomistic Simulation Study of Nanoparticle Effect on Nano-Cutting Mechanisms of Single-Crystalline Materials

Micromachines ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 265 ◽  
Author(s):  
Pengyue Zhao ◽  
Qi Zhang ◽  
Yongbo Guo ◽  
Huan Liu ◽  
Zongquan Deng
Keyword(s):  
Plastic Deformation ◽  
Surface Quality ◽  
Cutting Tool ◽  
Deformation Mechanisms ◽  
Relative Depth ◽  
Machined Surface ◽  
Workpiece Surface ◽  
Single Crystalline ◽  
Machined Surface Quality ◽  
Cutting Mechanisms

Nanoparticle (NP), as a kind of hard-to-machine component in nanofabrication processes, dramatically affects the machined surface quality in nano-cutting. However, the surface/subsurface generation and the plastic deformation mechanisms of the workpiece still remain elusive. Here, the nano-cutting of a single-crystalline copper workpiece with a single spherical embedded nanoparticle is explored using molecular dynamics (MD) simulations. Four kinds of surface/subsurface cases of nanoparticle configuration are revealed, including being removed from the workpiece surface, moving as a part of the cutting tool, being pressed into the workpiece surface, and not interacting with the cutting tool, corresponding to four kinds of relative depth ranges between the center of the nanoparticle and the cutting tool. Significantly different plastic deformation mechanisms and machined surface qualities of the machined workpiece are also observed, suggesting that the machined surface quality could be improved by adjusting the cutting depth, which results in a change of the relative depth. In addition, the nanoparticle also significantly affects the processing forces in nano-cutting, especially when the cutting tool strongly interacts with the nanoparticle edge.

Investigation on Machined Surface Quality During Cutting of GH4169 Under High-Pressure Cooling

2020 ◽  
Vol 12 (7) ◽  
pp. 994-1003
Author(s):  
Ming-Yang Wu ◽  
Wei-Xu Chu ◽  
Ke-Ke Liu ◽  
Shu-Jie Wu ◽  
Yao-Nan Cheng
Keyword(s):  
Residual Stress ◽  
Plastic Deformation ◽  
High Pressure ◽  
Tensile Stress ◽  
Surface Quality ◽  
Work Hardening ◽  
Surface Plastic ◽  
Residual Tensile Stress ◽  
Machined Surface ◽  
Machined Surface Quality

The aerospace component material GH4169 has low thermal conductivity and poor machinability, resulting in difficulty to guarantee good surface quality after conventional cutting. High-pressure cooling assisted machining technology can effectively improve the problem. In order to study the effect of high-pressure cooling assisted processing technology on the machined surface quality of GH4169, in this paper, Deform-3D was first used to construct a thermo-mechanical coupling finite element model for turning GH4169 under high-pressure cooling conditions, to analyze the turning temperature and surface residual stress. Then, analysis was carried out on the residual stress, work hardening behavior, and metamorphic layer of the GH4169 machined surface, in combination with the turning experiment. The results show that, under the conditions of little feeding and highspeed cutting, the GH4169 turning surface generates residual tensile stress along with both the feeding and turning directions. Moreover, the residual tensile stress gradually turns into the residual compressive stress along the depth direction. The application of high-pressure coolant can reduce the residual tensile stress of the machined surface. As the cooling pressure increases, the residual tensile stress of the machined surface decreases. The coupling effect between thermal deformation and plastic deformation when turning GH4169 can cause the work hardening of the surface, and the hardening degree decreases with the increase of cooling pressure. The high-pressure cooling assisted machining technology can effectively reduce surface plastic deformation, and promote the lessening of grain refinement degree of the material surface, thereby reducing the thickness of the metamorphic layer.

Experimental Investigations into Machining of FRP Material

2016 ◽  
Vol 836-837 ◽  
pp. 29-35
Author(s):  
Pavel Zeman ◽  
Petr Kolar ◽  
Petr Masek
Keyword(s):  
Surface Quality ◽  
Cutting Forces ◽  
Cutting Tool ◽  
Cutting Tools ◽  
Cellulose Fibre ◽  
Experimental Investigations ◽  
Tool Geometry ◽  
Machined Surface ◽  
Milling Operations ◽  
Machined Surface Quality

Machining of fibre-reinforced thermosets is becoming a very popular technology today. Nevertheless, machinability of these materials is rather different from conventional materials such as metals since hard and abrasive fibres are combined with relatively soft resin with low glass transition temperature. Special attention has to be given to workpiece quality because delamination and burning of machined surface can occur. An experimental investigation into machinability of a polymeric and cellulose fibre-reinforced resin material was carried out. Milling operations were inspected with respect to process temperature, cutting forces and machined surface quality. The effect of cutting conditions on the mentioned aspects was determined. Standard and tailored cutting tools were used in the investigation. It was observed that surface quality is strongly dependent on tool geometry, milling strategy, fibre orientation and feed. On the other hand, cutting forces are relatively low and dependent on tool geometry and feed. The modified cutting tool with more positive tool geometry showed better results compared to the conventional one.

scholarly journals Effect of Shift in Speed Turning on Machined Surface Quality

2017 ◽  
Vol 65 (1) ◽  
pp. 135-143
Author(s):  
Pavel Polák ◽  
Petr Dostál ◽  
Katarína Kollárová
Keyword(s):  
Mild Steel ◽  
Surface Quality ◽  
Cutting Tool ◽  
Hardened Steel ◽  
Cutting Conditions ◽  
Machined Surface ◽  
Machined Surface Quality ◽  
The Given ◽  
Machined Surfaces ◽  
Thermally Treated

This article describes the evaluation of machined material roughness in speed turning on a machining centre Doosan Puma 700 LY. The machined surface of semi-finished products from steel 14 260 was compared at selected cutting conditions. A half of compared samples from steel 14 260 was in the original, thermally untreated condition (mild steel), and the second half of samples was thermally treated (hardened steel, with a hardness of samples 50 HRC). The experiment focused on turning the selected samples in order to evaluate the roughness of machined surfaces. Cutting tool shift was variable during individual measurements. This experiment contributes to a quick orientation in the given issue and points out to optimisation of cutting conditions.

Study on the Cutting Force and Machined Surface Quality of Milling AFRP

2016 ◽  
Vol 836-837 ◽  
pp. 155-160 ◽  
Author(s):  
Si Qi Liu ◽  
Yan Chen ◽  
Yu Can Fu ◽  
An Dong Hu
Keyword(s):  
Cutting Force ◽  
Surface Quality ◽  
Cutting Tool ◽  
Cutting Tools ◽  
Cutting Parameters ◽  
Helix Angle ◽  
End Mill ◽  
Machined Surface ◽  
Reinforced Plastics ◽  
Machined Surface Quality

AFRP(Aramid Fiber Reinforced Plastics) is widely used in the aerospace and automotive while there are many problems in machining AFRP such as furry, delamination, burns and so on. Milling experiments of AFRP have been conducted to study the influence of different helix angle (0°, 30°, 60°) and cutting tools (traditional end mill, multiple flute end mill and compression end mill) on cutting force and machined surface quality. The results indicated that the cutting force has been reduced and the surface quality has been improved with the increase of helix angle. The cutting tool structure can make greater influence on machined surface quality than the cutting parameters. A cutting tool with the structure of multiple flute or herringbone cutting edge could reduce the axial cutting force. However the cutting force is too small to cut off fibers when using a multiple flute end mill. A good processing surface can be achieved while cutting with a compression end mill or a tool with big helix angle.

scholarly journals Effect of Coating and Polishing of Cutting Tool on Machined Surface Quality in Dry Machining of Aluminium Alloy

2020 ◽  
Vol 70 (3) ◽  
pp. 299-305
Author(s):  
Atul Dev ◽  
Smriti Tandon ◽  
Pankaj Kumar ◽  
Anup Dutt
Keyword(s):  
Aluminium Alloy ◽  
Surface Quality ◽  
Surface Finish ◽  
Cutting Tool ◽  
Machining Process ◽  
Dry Machining ◽  
Machined Surface ◽  
Machined Surface Quality ◽  
Flute Surface ◽  
Machining Parameter

Surface quality is one of the major concerns in any machining process. To achieve the higher surface finish, mostly concentrated on machining parameter optimisation. This study has been carried out to study the effect of coating and polishing of flute surface of the solid carbide (WC-Co) endmill cutters on machined surface quality obtained during dry machining of Aluminium alloy 24345WP. Experiments were conducted on Aluminum workpieces with Ø6 mm 2 flute end- mill cutter with and without coating/polishing and their effect on surface quality studied for linear as well as areal surface roughness parameters using white light interferometery. The study concludes that polished flute tool, despite their non-sharp cutting edges, gives considerably better surface finish due to its lowering of chip tool friction. This was also supported by the results obtained from scanning electron microscopy of the cutting tool edge as well as optical microscopy of the obtained machined surface.

scholarly journals The Comparative Study on Cutting Performance of Different-Structure Milling Cutters in Machining CFRP

2018 ◽  
Vol 8 (8) ◽  
pp. 1353
Author(s):  
Tao Chen ◽  
Fei Gao ◽  
Suyan Li ◽  
Xianli Liu
Keyword(s):  
Carbon Fiber ◽  
Cutting Force ◽  
Surface Quality ◽  
Cutting Edge ◽  
Cutting Performance ◽  
Machining Process ◽  
Carbon Fiber Composites ◽  
Machined Surface ◽  
Milling Cutter ◽  
Machined Surface Quality

Carbon fiber reinforced plastic (CFRP) is typically hard to process, because it is easy for it to generate processing damage such as burrs, tears, delamination, and so on in the machining process. Consequently, this restricts its wide spread application. This paper conducted a comparative experiment on the cutting performance of the two different-structure milling cutters, with a helical staggered edge and a rhombic edge, in milling carbon fiber composites; analyzed the wear morphologies of the two cutting tools; and thus acquired the effect of the tool structure on the machined surface quality and cutting force. The results indicated that in the whole cutting, the rhombic milling cutter with a segmented cutting edge showed better wear resistance and a more stable machined surface quality. It was not until a large area of coating shedding occurred, along with chip clogging, that the surface quality decreased significantly. At the stage of coating wear, the helical staggered milling cutter with an alternately arranged continuous cutting edge showed better machined surface quality, but when the coating fell off, its machined surface quality began to reveal damage such as groove, tear, and fiber pullout. Meanwhile, burrs occurred at the edge and the cutting force obviously increased. By contrast, for the rhombic milling cutter, both the surface roughness and cutting force increased relatively slowly.

Research on Grinding Force of Zirconia Internal Grinding with Resin Bond Diamond Wheel

2016 ◽  
Vol 1136 ◽  
pp. 30-35
Author(s):  
He Wang ◽  
Ke Zhang ◽  
Yu Hou Wu ◽  
Hong Song
Keyword(s):  
Grain Size ◽  
Surface Quality ◽  
Diamond Wheel ◽  
Grinding Force ◽  
Wheel Speed ◽  
Zirconia Ceramic ◽  
Machined Surface ◽  
Research Results ◽  
Internal Grinding ◽  
Machined Surface Quality

The zirconia parts are limited by machined surface quality. The grinding force is one of the most important parameters of grinding and has effects on surface quality. The MK2710 grinder and resin bond diamond wheels were used in zirconia grinding. The grinding force was obtained by Kistler dynamometer. The paper focused on wheel speed and grain size on grinding force, and examined the surface by SEM. The research results indicated that decreasing the grain size, the grinding force increased and the surface quality improved, and increasing wheel speed could decrease grinding force to improve grinding surface quality. The results can improve zirconia ceramic parts surface quality and promote application.

Evaluation of DPI Change Impact on Laser Machined Surface Quality

2014 ◽  
Vol 474 ◽  
pp. 369-374
Author(s):  
Jana Knedlova ◽  
Libuše Sýkorová ◽  
Vladimír Pata ◽  
Martina Malachová
Keyword(s):  
Surface Roughness ◽  
Surface Quality ◽  
Laser Micromachining ◽  
Technological Parameters ◽  
Machined Surface ◽  
Machined Surface Quality ◽  
Machined Surface Roughness ◽  
Change Impact

The article focuses on the field of PMMA laser micromachining at change of the technological parameters. The aim was to evaluate machined surface roughness at different setting of DPI definition (number of dots paths on square inch). Commercial CO2laser Mercury L-30 by firm LaserPro, USA was used for experimental machining. Ray of laser could be focused on mark diameter d=185 mm.

Device for Wood-Cutting Tool Hardening

2021 ◽  
pp. 134-141
Author(s):  
Anatoly M. Buglaev ◽  
Keyword(s):  
Plastic Deformation ◽  
Surface Quality ◽  
Cutting Tool ◽  
Cutting Tools ◽  
Surface Plastic Deformation ◽  
Surface Plastic ◽  
Labour Intensity ◽  
Machine Parts ◽  
Wood Cutting ◽  
Electrospark Hardening

Choosing effective methods and devices for surface hardening of wood-cutting tools is problematic due to the variety of their designs and operating conditions. In this regard, the development of such devices becomes an urgent task. According to the literature, one of the effective methods for increasing the service life of machine parts and tools is electrospark hardening or electrospark alloying. Industrial electrospark installations such as “EFI” (electrophysical measurements) and “Elitron” with manual vibrators are used for electrospark hardening. However, using manual vibrators significantly increases the labour intensity and hardening time. Moreover, the surface quality after hardening with manual vibrators is often unsatisfactory. Various mechanized installations have been developed in order to reduce the labour intensity of electrospark hardening. Nevertheless, these installations are designed to harden specific parts and do not allow hardening tools of various designs, including woodcutting tools. The surface quality after hardening in mechanized installations does not always satisfy the customer. Further surface plastic deformation treatments, such as rolling and unrolling with rollers and balls, as well as diamond burnishing, are often used to improve the surface quality after electrospark hardening. The surface quality after additional processing by these methods boosts, although the labour intensity and cost of the hardening process increase. To increase the wear resistance of machine parts and tools, it is reasonable to reduce the height parameters of roughness, increase microhardness, and form the residual compressive stresses, which is ensured by the methods of surface plastic deformation. In this regard, it becomes necessary to use electrospark hardening simultaneously with surface plastic deformation. The work presents the design and features of using the device for hardening. The device was used to strengthen the thicknesser machine knives, which made it possible to almost double their durability. Applying this device, in comparison with using the electrospark hardening with a manual vibrator, reduces the roughness of the hardened surface and improves the surface quality of the processed workpieces. The modes of hardening have been installed, making it possible to effectively harden wood-cutting tools. For citation: Buglaev A.M. Device for Wood-Cutting Tool Hardening. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 5, pp. 134–141. DOI: 10.37482/0536-1036-2021-5-134-141

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