Analysis of electrical contact surface characteristics of aeronautical electrical circuit based on infrared thermography

AbstractThe study attempted to observe the surface characteristics of the flank lock type precision locknut which was assembled in a vertical type and operates under different tightening speed. The speed setting was in according with the specifications of 4rpm, 6rpm and 8rpm conditions to set up this experiment. A type of 2TML lubricant was used. The experiment investigated the surface characteristics of a locknut, including contact surface flatness, contact surface roughness, and thread surface roughness before and after the designed test. According to the contact surface flatness of the locknut obtained from this study, it was found that the surface of the locknut contacting with the bearing resulted into a deterioration of the surface flatness and surface roughness during the tests. Furthermore, the thread surface roughness has been changed at different thread for different tightening speed during the test, especially at threads 1, 2, 7 and 8. The study found that some of variations occurred in the values of Ra, Rz and Rmax at different thread of a locknut. The variation of Rmax is the most among them.

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Contact Surface Characteristics

Friction and Wear of Ceramics ◽

10.1002/9781119538790.ch5 ◽

2020 ◽

pp. 103-118

Keyword(s):

Contact Surface ◽

Surface Characteristics

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Observations of electrical contact surface in CuAg/Ni couple with make/break

10.1109/holm.1990.113028 ◽

2002 ◽

Author(s):

F. Honda ◽

Y. Imada ◽

K. Okumura ◽

K. Nakajima

Keyword(s):

Contact Surface ◽

Electrical Contact

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A New Silver-Based Graded Composite as Electrical Contact Material

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.2616 ◽

2007 ◽

Vol 336-338 ◽

pp. 2616-2618 ◽

Cited By ~ 2

Author(s):

Lu Wang ◽

Yong Zhao ◽

X.T. Zhu ◽

Y. Wang

Keyword(s):

Surface Layer ◽

Metal Oxides ◽

Contact Surface ◽

Electrical Contact ◽

Functionally Graded ◽

Operating Parameters ◽

Contact Material ◽

Contact Materials ◽

Electrical Contact Material ◽

Graded Material

Silver metal oxides (Ag/MeO) are extensively used as electrical contact materials in switching systems. A contact material with ideal operating parameters is very difficultly fabricated by conventional manufacturing techniques. In this paper, a new electrical contact material characterized by graded distributions of different oxides in Ag matrix was fabricated in order to optimize the distributions of operating parameters in material bulk instead of to enhance synchronously properties of that on contact surface. Two selected metal oxides, NiO and SnO2, were doped into Ag matrices, of which one surface layer NiO 12wt% was doped and another SnO2 12wt%, and the concentrations of NiO and SnO2 were varied gradually in bulk. The electrical contact test results show that the average operating number of NiO doped surface layer of graded Ag composite as contact surface is 4600 under 20A current and 220V AC voltage without melted welding while that of samples doped uniformly with NiO is 2200 under the same testing conditions. However, the average loss of mass due to arc erosion of graded samples is higher than that of uniform samples. We conclude that the functionally graded material (FGM) concept has potential application for electric contact materials.

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Analysis of arc existence in electrical contact gap for 42 V automotive DC components

International Journal of Emerging Electric Power Systems ◽

10.1515/ijeeps-2019-0202 ◽

2020 ◽

Vol 21 (4) ◽

Author(s):

Femi Robert

Keyword(s):

Electric Field ◽

Low Cost ◽

Electrical Contact ◽

Software Tool ◽

Electrical Circuit ◽

Electrical Contacts ◽

Dc System ◽

Power Characteristics ◽

Finite Element Software ◽

Dc Power

AbstractIn this paper, the existence of arc in an electrical contact gap is investigated. A 14 and 42 V DC electrical circuit for an automotive vehicle is considered and the factors which causes arc are identified. A plate–plate, cylinder–cylinder and cone–cone electrical contact are considered for which the closed-state resistance and open-state capacitance are acquired for Al, Cu, Fe, Ni, Au and Pt materials. The voltage, current and power characteristics curves of the electrical contact are obtained for the equivalent automotive DC system. The temperature and electric field of the electrical contact is also reported. The breakdown voltage and electric field for the micro-gaps of 0.5–10 µm are presented and the boundary for arcless operation of the electrical contact is identified. Arc existence is analyzed for four circuit conditions with various voltage and current levels. Simulations are executed using COMSOL Multiphysics Finite Element software tool and the results were related with calculated values. The results show that power has more influence on the arc existence in electrical contact. Electrical contact does not produce an arc due to voltage and electric field. The plate–plate electrical contact with Pt material performs better in terms of arcless switching. These electrical contacts would have an influential role in the design of an arcless, less weight, low cost, reliable electrical contact for next-generation automotive DC power system.

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