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Properties of the subsurface layer after rolling burnishing of an initially milled aluminium alloy

Kalisz J., Grzesik W., Zak K., Czechowski K.

Journal of Machine Engineering

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2017

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Vol. 17, No. 3

66--74

EN

This paper characterizes mechanical properties of the technological subsurface layer produced by medium milling of EM AW-AlCu4MgSi(A) aluminium alloy in hardened state T451 using a ball-end cutter and subsequent roller burnishing using a nitride ceramic ball. It was revealed that ball burnishing operations performed on curvilinear milled surfaces allow obtaining the subsurface layer with a minimum strain-hardening effect and induced compressive residual stresses without visible microstructural changes. As a result, such functional properties of the subsurface layer as fatigue strength, bearing properties and contact strength along with a very smooth machined surface of the Sa roughness of about 0.02 µm can be ensured.

2

Areal field and fractal based characterization of hard surfaces produced by different machining operations

Zak K.

Journal of Machine Engineering

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2016

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Vol. 16, No. 1

24--32

EN

This literature survey highlights the possible influences of surface roughness parameters on functional properties of surfaces produced by different finishing operations. The prediction of such functional properties as fatigue, sealing capacity, adhesion, friction, wear and corrosion resistance based on five groups of spatial (S) roughness parameters is overviewed. In contrast, traditional approach based on 2D roughness parameters is provided. Some real 3D surface topographies produced with desired functional properties by finishing cutting and abrasive operations are characterized. This survey confirms the vital role of machined surfaces in the functionality of machine components.

3

Numerical 3D FEM Simulation and Experimental Analysis of Tribological Aspects in Turning Inconel 718 Alloy

Nieslony P., Grzesik W., Laskowski P, Zak K.

Journal of Machine Engineering

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2015

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Vol. 15, No. 1

46--57

EN

This paper presents 3D FEM simulation results performed for the power law and JC (Johnson-Cook) material constitutive models for two sets of friction parameters. The friction conditions were tested using pin-on-disc tribometer. Machining tests were carried out using carbide cutting tools coated with a TiAlN monolayer without coolants. The selection of machining conditions was based on real production data. In addition, a real CAD model of the cutting tool insert was implemented. Moreover, an advanced technique of meshing the cutting edge and the grooved rake face was applied. The simulations include cutting forces and cutting temperature. Finally, FEM simulations were compared with measurements in order to improve the simulation strategy.

4

Characteristics of Surface Topography after Rolling Burnishing of EM AW-AlCu4MgSi(A) Aluminium Alloy

Kalisz J., Zak K., Grzesik W., Czechowski K.

Journal of Machine Engineering

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2015

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Vol. 15, No. 1

71--80

EN

This paper characterizes surface topographies produced by medium milling of EM AW-AlCu4MgSi(A) aluminium alloy in hardened state T451 using a ball-end cutter of 8 mm diameter and subsequent finish by roller burnishing using a Si3N4 nitride ceramic ball of 8mm diameter. It was revealed that ball burnishing operations performed on curvilinear milled surfaces allow obtaining the machined surfaces of high quality and exceptional smoothness with different textures and, as a result, ensuring demanded functional properties such as fatigue strength, bearing properties and contact strength [1]. It was experimentally verified that precision ball burnishing performed with a low stepover of 0.04mm produced a very smooth with the Sa roughness of about 0.02 µm characteristic for polishing.