FEM Simulation and Experiment of High-Pressure Cooling Effect on Cutting Force and Machined Surface Quality During Turning Inconel 718

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.

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Study on the cutting performance in machining assembled hardened steel workpiece with torus cutter

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405419889200 ◽

2019 ◽

Vol 234 (4) ◽

pp. 701-709

Author(s):

Tao Chen ◽

Weijie Gao ◽

Guangyue Wang ◽

Xianli Liu

Keyword(s):

Tool Wear ◽

Cutting Force ◽

Surface Quality ◽

Wear Mechanism ◽

Hardened Steel ◽

Cutting Performance ◽

Machining Process ◽

Machined Surface ◽

Machined Surface Quality ◽

Two Sides

Torus cutters are increasingly used in machining high-hardness materials because of high processing efficiency. However, due to the large hardness variation in assembled hardened steel workpiece, the tool wear occurs easily in machining process. This severely affects the machined surface quality. Here, we conduct a research on the tool wear and the machined surface quality in milling assembled hardened steel mold with a torus cutter. The experimental results show the abrasive wear mechanism dominates the initial tool wear stage of the torus cutter. As the tool wear intensifies, the adhesive wear gradually occurs due to the effect of alternating stress and impact load. Thus, the mixing effect of the abrasive and adhesive wears further accelerates tool wear, resulting in occurrence of obvious crater wear band on the rake face and coating tearing area on the flank face. Finally, the cutter is damaged by the fatigue wear mechanism, reducing seriously the cutting performance. With increase of flank wear, moreover, there are increasingly obvious differences in both the surface morphology and the cutting force at the two sides of the joint seam of the assembled hardened steel parts, including larger height difference at the two sides of the joint seam and sudden change of cutting force, as a result, leading to decreasing cutting stability and deteriorating seriously machined surface quality.

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

Science of Advanced Materials ◽

10.1166/sam.2020.3738 ◽

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.

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Study of High Efficiency in Green Cutting Nickel-Based Superalloy GH4169

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.33.555 ◽

2010 ◽

Vol 33 ◽

pp. 555-559

Author(s):

Rong Di Han ◽

Hui Wang ◽

Y. Zhang ◽

Q.W. Yao

Keyword(s):

Water Vapor ◽

Tool Wear ◽

Cutting Force ◽

Surface Quality ◽

Tool Life ◽

Cutting Temperature ◽

Dry Cutting ◽

Machined Surface ◽

Nickel Based Superalloy ◽

Machined Surface Quality

The machinability of nickel-based superalloy GH4169 is very poor, the traditional machining of GH4169 using the cutting fluids with the active additives causes environmental and health problems, which is out of the request of the sustainable development strategy. In this paper a new green cutting technology with overheated water vapor as coolants and lubricants was proposed to achieve the aim of green cutting and high productivity. Cutting experiments and tool wear tests using carbide tool YG6 under dry cutting, emulsion and water vapor were performed. The cutting force, cutting temperature, machined surface quality and tool life were investigated; the curve of flank tool wear and relation between tool life and cutting velocity was carried out. The results of experiments indicated that during water vapor condition, the cutting force and cutting temperature was reduced, the machined surface roughness was improved, and the tool life was longed, respectively, and the higher velocity was taken during the some tool wear condition compared to dry cutting. The research results show that green cutting was achieved associated with overheated water vapor cooling and lubricating, at he same time the machined surface quality and production efficiency was increased.

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Influence of Lubricant Environment on Machined Surface Quality in Single-Point Diamond Turning of Ferrous Metal

Micromachines ◽

10.3390/mi12091110 ◽

2021 ◽

Vol 12 (9) ◽

pp. 1110

Author(s):

Menghua Zhou ◽

Jianpeng Wang ◽

Guoqing Zhang

Keyword(s):

Surface Morphology ◽

Cutting Force ◽

Surface Quality ◽

Single Point ◽

Ferrous Metal ◽

Minimum Quantity Lubrication ◽

Diamond Turning ◽

Machined Surface ◽

Hard Particles ◽

Machined Surface Quality

In the field of single-point diamond turning (SPDT), machining ferrous metal is an important research topic with promising application. For SPDT of ferrous metal, the influence of lubricant on the workpiece surface morphology remains to be studied. In this study, three lubricant machining environments were selected to carry out specific control experiments. The machined surface morphology and cutting force in different lubricant machining environments were analyzed. The experiment results showed that the lubricant environment will have significant impacts on the quality of the machined surface morphology of ferrous metal. In the environment of minimum quantity lubrication machining (MQLM-oil), better machined surface quality can be obtained than that in ordinary dry machining (ODM) and high-pressure gas machining (HGM). Furthermore, the cutting force captured in the ODM and HGM environment increased with the increase of the cutting depth, while the cutting force in the MQLM-oil environment remained almost unchanged. That indicates MQLM-oil can suppress the formation of hard particles to improve the machining quality.

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

Materials Science Forum ◽

10.4028/www.scientific.net/msf.836-837.155 ◽

2016 ◽

Vol 836-837 ◽

pp. 155-160 ◽

Cited By ~ 1

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.

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