Wyniki wyszukiwania - BazTech

1

Effect of Face Milling Parameters of Carbon Fiber Reinforced Plastics Composites on Surface Properties

Miturska-Barańska Izabela, Józwik Jerzy, Bere Paul

Advances in Science and Technology. Research Journal

|

2022

|

Vol. 16, no 2

26--38

EN

This paper analyses the influence of face milling process parameters on the surface properties of carbon fibre reinforced polymer. The influence of milling speed and feed per tooth on the surface properties was determined. The influence of cutting speed and feed per tooth on surface energy properties was determined. The object of research was a carbon fiber reinforced plastics (CFRP) composites plate made of carbon fibre in epoxy matrix. The tool used in the study was a double-edged end mill. The machining parameters used were variable: cutting speeds of 100 m·min-1, 120 m·min-1, 140 m·min-1 and 160 m·min-1, and feeds per tooth of 0.015 mm/tooth, 0.020 mm/tooth, 0.025 mm/tooth and 0.03 mm/tooth. The axial depth of cut and radial depth of cut was a constant parameter. After milling, tests were carried out on the surface contact angle, which was used to determine the surface free energy. Based on the contact angle measurements carried out with the sitting-drop method and the calculation of the surface free energy with the Owens-Wendt model, it was observed, that the increase in the value of the surface free energy is significantly influenced by the increase in the cutting speed.

2

Influence of the Length of Components from Polymer Composite on Selected Machinability Indicators in the Circumferential Milling Process

Ciecieląg Krzysztof

Advances in Science and Technology. Research Journal

|

2020

|

Vol. 14, no 4

229--239

EN

The article presents the results of the research on the influence of the length of elements made of carbon fiber reinforced plastics (CFRP) and glass fiber reinforced plastics (GFRP) on surface roughness, surface topography, passive forces and cutting torques after circumferential milling with diamond-coated inserts (PCD). The paper also presents the results of the research on the stiffness of the elements depending on their length. The samples of composite materials were clamped in a vise at the machining center. The length of the element was defined as the unsupported distance between the milled surface and the place of attachment of the composite element. With constant milling parameters, the maximum values and amplitudes of the values of passive forces and cutting torques at variable element lengths were determined. The obtained surface was measured in order to determine the surface roughness parameters and 3D topography. The research showed that the carbon fiber reinforced plastics is on average one and a half times stiffer than that the glass fiber reinforced plastics. On the basis of the results obtained, it was found that the passive forces and cutting torques as well as the roughness parameters increase along with the length of the element. It was also shown that for the glass fiber reinforced plastics, above a certain length, the surface roughness clearly deteriorates.

3

Effect of depth surface defects in carbon fibre reinforced composite material on the selected recurrence quantifications

Ciecieląg K., Kęcik K., Zaleski K.

Advances in Materials Science

|

2020

|

Vol. 20, nr 2(64)

71--80

EN

The paper discusses the problem of possibility of the detecting surface defects in carbon fibre reinforced plastics (CFRP) materials on the basis of the milling time series. First, the special defects in the hole-shaped with various depth were made. Next, the cutting forces are measured during the milling machining. Finally, the recurrence plot and quantification analysis was applied. The obtained results show that the depth defect influences the selected recurrence quantifications, which can be used as the simple defect indicators. The conducted research allow to determine the percentage share of the detectable defects. The novelty of the work and an unresolved problem is the selection of recurrence quantifications with the simultaneous use of them to detect the size of defects in carbon fibre reinforced plastics.

4

Investigations on mechanical properties and microtopography of electromagnetic self-piercing riveted joints with carbon fiber reinforced plastics/aluminum alloy 5052

Liang Jusong, Jiang Hao, Zhang Jinsheng, Wu Xianhe, Zhang Xu, Li Guangyao, Cui Junjia

Archives of Civil and Mechanical Engineering

|

2019

|

Vol. 19, no. 1

240--250

EN

In this paper, the mechanical properties of electromagnetic self-piercing riveted (E-SPR) joints with carbon fiber reinforced plastics (CFRP)/aluminum alloy (Al) 5052 were comprehensively investigated. Microtopography observations, hardness measurements and tensile-shear strength tests were performed by comparing with regular pressure self-piercing riveted (P-SPR) joints. Results showed that the undercut value of E-SPR joints was higher than that of P-SPR joints. The hardness values on rivet legs of E-SPR joints were larger and almost no difference on rivet heads between the E-SPR and P-SPR. In addition, it was found that mechanical properties of E-SPR joints were higher than that of P-SPR joints. The shear fracture appearance indicated that E-SPR joints with higher undercut were more difficult to rupture in the bottom of Al sheet.

5

Development of Crash Absorbers Made of Carbon Fibre-Reinforced Plastic Based on Experimental Studies

Szlosarek R., Bombis F., Mühler M., Kröger M.

Machine Dynamics Research

|

2015

|

Vol. 39, No. 4

65-72

EN

Crash absorbers made of carbon fibre-reinforced plastics (CFRP) become more and more popular to reduce mass in the front structure of cars. One open question in this issue is the correct layup, which specifies the fibre orientation, in order to obtain high specific energy absorption. Within the research, a first test series investigates crash absorbers with a fibre orientation in axial and circumferential direction and an orientation of ±45°. Based on these first experimental studies an optimisation of the layup results in a crash absorber made of CFRP with a significant higher specific energy absorption than a comparable crash absorber made of aluminium.

6

Application of fibre composites in a spindle ram design

Kulisek V., Janota M., Ruzicka M., Vrba P.

Journal of Machine Engineering

|

2013

|

Vol. 13, No. 1

7--23

EN

When compared to steel or cast iron, carbon fibre composites offer excellent tensile and bending stiffness together with significantly smaller density. Research at the Research centre of Manufacturing Technologies in Prague has been aimed at the application of composite materials in structural parts design. Case studies on spindle rams were performed focusing on the design of experimental composite spindle rams and their benchmarking with reference steel components. The cross-section of both parts was 350x350mm and the length was 1200mm. The first design was made as a thick-walled composite body with a minimal amount of steel. The goal was to achieve static stiffness comparable to a reference steel component of the same size. The second design was manufactured as a hybrid structure composed of fibre composites with cork layers and bonded steel reinforcements. The goal was to improve damping of the structural parts in comparison with the steel components. Results of stiffness and modal properties were obtained from experiments and also using FEA. Experimentally obtained damping ratios of composite and reference steel rams were compared with and without the effect of connection interfaces on damping.