Effects of cryogenic cooling by liquid nitrogen jets on tool wear, surface finish and dimensional deviation in turning different steels

Background: As an important method of remanufacturing, laser cladding can be used to obtain the parts with specific shapes by stacking materials layer by layer. The formation mechanism of laser cladding determines the “Staircase effect”, which makes the surface quality can hardly meet the dimensional accuracy of the parts. Therefore, the subsequent machining must be performed to improve the dimensional accuracy and surface quality of cladding parts. Methods: In this paper, chip formation, cutting force, cutting temperature, tool wear, surface quality, and optimization of cutting parameters in the subsequent cutting of laser cladding layer are analyzed. Scholars have expounded and studied these five aspects but the cutting mechanism of laser cladding need further research. Results: The characteristics of cladding layer are similar to that of difficult to machine materials, and the change of parameters has a significant impact on the cutting performance. Conclusion: The research status of subsequent machining of cladding layers is summarized, mainly from the aspects of chip formation, cutting force, cutting temperature, tool wear, surface quality, and cutting parameters optimization. Besides, the existing problems and further developments of subsequent machining of cladding layers are pointed out. The efforts are helpful to promote the development and application of laser cladding remanufacturing technology.

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Cutting Tool Wear and Mechanisms of Chip Formation During High-Speed Machining of Compacted Graphite Iron

ASME/STLE 2007 International Joint Tribology Conference, Parts A and B ◽

10.1115/ijtc2007-44026 ◽

2007 ◽

Author(s):

Niniza S. P. Dlamini ◽

Iakovos Sigalas ◽

Andreas Koursaris

Keyword(s):

Tool Wear ◽

Surface Finish ◽

Failure Criterion ◽

Cutting Tool ◽

Flank Wear ◽

Cutting Tools ◽

Compacted Graphite Iron ◽

Crater Wear ◽

Compacted Graphite ◽

Cutting Speeds

Cutting tool wear of polycrystalline cubic boron nitride (PcBN) tools was investigated in oblique turning experiments when machining compacted graphite iron at high cutting speeds, with the intention of elucidating the failure mechanisms of the cutting tools and presenting an analysis of the chip formation process. Dry finish turning experiments were conducted in a CNC lathe at cutting speeds in the range of 500–800m/min, at a feed rate of 0.05mm/rev and depth of cut of 0.2mm. Two different tool end-of-life criteria were used: a maximum flank wear scar size of 0.3mm (flank wear failure criterion) or loss of cutting edge due to rapid crater wear to a point where the cutting tool cannot machine with an acceptable surface finish (surface finish criterion). At high cutting speeds, the cutting tools failed prior to reaching the flank wear failure criterion due to rapid crater wear on the rake face of the cutting tools. Chip analysis, using SEM, revealed shear localized chips, with adiabatic shear bands produced in the primary and secondary shear zones.

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Modeling of Cutting Process with Cutter Axis Inclination

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.223.66 ◽

2011 ◽

Vol 223 ◽

pp. 66-74 ◽

Cited By ~ 3

Author(s):

Takashi Matsumura

Keyword(s):

Tool Wear ◽

Surface Finish ◽

Cutting Temperature ◽

Cutting Process ◽

Mechanistic Models ◽

End Mill ◽

High Quality ◽

Ball End Mill ◽

Milling Operations ◽

Edge Roughness

Multi-axis controlled machining has been increasing with the demand for high quality in mold manufacturing. The cutter axis inclination should be properly determined in the milling operations. The paper discusses the cutting process of ball end mill with the cutter axis inclination. Two mechanistic models are presented to show the effect of the cutter axis inclination on the tool wear and the surface finish. The actual cutting time during a rotation of the cutter reduces with increasing the cutter axis inclination. Then, the tool is cooled in the non-cutting time. The tool wear is suppressed with reducing the cutting temperature. The surface finish is also improved by increasing cutting velocities with the cutter axis inclination. When the cutter is inclined in the feed direction, the effect of the edge roughness on the surface finish is eliminated. The discussion based on the simulation is verified in the cutting tests for brittle materials.

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