Analysis of surface roughness morphology with TRIZ methodology in automotive electrical contacts: Design against third body fretting-corrosion

This paper investigates the influence of different number of laser pulses on contact behavior and conductivity of the surface layer of femtosecond laser microstructured, sulfur-doped silicon. Single shot laser processed silicon (Pink Silicon) is characterized by low surface roughness, whereas five shot laser processed silicon (Grey Silicon) has an elevated sulfur content with a surface roughness low enough to maintain good contacting. To laterally confine the laser induced pn-junction part of the Grey Silicon sample surface is etched off. The etching depth is confirmed to be sufficient to completely remove the active n-type sulfur layer. While Pink Silicon shows little or no lateral conductivity within the laser processed layer, Grey Silicon offers acceptable conductivity, just as expected by the fact of having incorporated a higher sulfur dopant content. Recombination dominates the irradiated regions of Pink Silicon and suppresses excess charge carrier collection. Grey Silicon, while showing sufficient lateral conductivity, still shows regions of lower conductivity, most likely dominated by the laser irradiation-induced formation of dislocations. According to our results, the optimum laser pulse number for electrical and structural properties is expected to be in the range between one and five laser pulses.

Download Full-text

Intermittence detection in fretting corrosion studies of electrical contacts

Electrical Contacts - 1997 Proceedings of the Forty-Third IEEE Holm Conference on Electrical Contacts ◽

10.1109/holm.1997.637868 ◽

2002 ◽

Cited By ~ 35

Author(s):

S.R. Murrell ◽

S.L. McCarthy

Keyword(s):

Electrical Contacts ◽

Fretting Corrosion ◽

Corrosion Studies

Download Full-text

Influence of Surface Roughness on Friction and Contact Resistance in Sliding Electrical Contacts

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

10.1115/ijtc2007-44355 ◽

2007 ◽

Author(s):

Dinesh G. Bansal ◽

Jeffrey L. Streator

Keyword(s):

Surface Roughness ◽

Contact Resistance ◽

Coefficient Of Friction ◽

Electrical Contact ◽

Electrical Current ◽

Electrical Contacts ◽

Sliding Electrical Contacts ◽

The Coefficient Of Friction ◽

Current Densities

An experiment is conducted to investigate the role of surface roughness on the coefficient of friction and contact resistance of sliding electrical contacts. A hemispherical pin is sliding along both smooth and rough 2-meter rail surface. Tests are performed at both low and moderate sliding speed and for a range of electrical current densities, ranging from 0 to about 12 GA/m2. It was found that surface roughness had a significant influence on the coefficient of friction, with the smoother surfaces exhibiting higher coefficients of friction. Contact resistance, on the other hand, did not show as strong an effect of surface roughness, except for a few parameter combinations. At the higher current densities studied (>10 GA/m2), it was found that the contact resistance values tended to be on the order of 1 mΩ, independent of load, speed and roughness. This convergence may be due to presence of liquid metal film at the interface, which established ideal electrical contact.

Download Full-text

Fretting corrosion of tin-coated electrical contacts

Microelectronics Reliability ◽

10.1016/0026-2714(88)90160-6 ◽

1988 ◽

Vol 28 (4) ◽

pp. 654

Keyword(s):

Electrical Contacts ◽

Fretting Corrosion

Download Full-text

Wear of Electric Contact Surfaces

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

10.1115/ijtc2007-44315 ◽

2007 ◽

Cited By ~ 1

Author(s):

J. Song

Keyword(s):

Wear Resistance ◽

Precious Metals ◽

Electrical Contacts ◽

Fretting Corrosion ◽

Coating Materials ◽

Long Term Stability ◽

Electric Contacts ◽

Contact Surfaces ◽

Contact Shape

Fretting corrosion is one of the important factors which limits the lifetime of electric contacts. In order to avoid fretting corrosion coatings of different precious metals are used. The wear resistance of the coating determines the lifetime of electrical contacts. The long term characteristics of gold coated electrical contacts with different additives and contact shapes are investigated and the results are analyzed. It is found out that the wear resistance of contact coating can be largely influenced by the amount of the additive in gold and by the design of the contact shape. Only the combination of an optimized contact shape with suitable coating materials leads to a long term stability of electric contacts.

Download Full-text

Correlation between Wear Resistance and Lifetime of Electrical Contacts

Advances in Tribology ◽

10.1155/2012/893145 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 13

Author(s):

Jian Song ◽

Christian Koch ◽

Liangliang Wang

Keyword(s):

Electrical Conductivity ◽

Wear Resistance ◽

High Performance ◽

Electrical Contacts ◽

Electrical Performance ◽

High Wear Resistance ◽

High Electrical Conductivity ◽

Fretting Corrosion ◽

Long Lifetime

Electrical contacts are usually plated in order to prevent corrosion. Platings of detachable electrical contacts experience wear because of the motion between contacts. Once the protecting platings have been worn out, electrical contacts will fail rapidly due to corrosion or fretting corrosion. Therefore the wear resistance of the platings is a very important parameter for the long lifetime of electrical contacts. Many measures which improve the wear resistance can diminish the conductivity of the platings. Due to the fact that platings of electrical contacts must have both a high wear resistance and a high electrical conductivity, the manufacturing of high performance platings of electrical contacts poses a great challenge. Our study shows firstly the correlation between the wear resistance of platings and lifetime of electrical contacts and then the measures, which improve the wear resistance without impairing the electrical performance of the contacts.

Download Full-text

Photovoltaic Solar Textiles

Proceedings ◽

10.3390/proceedings2019032004 ◽

2019 ◽

Vol 32 (1) ◽

pp. 4

Author(s):

Wilson ◽

Mather

Keyword(s):

Thin Film ◽

Surface Roughness ◽

Solar Cells ◽

Electrical Contacts ◽

Silicon Wafers ◽

The Other ◽

Flexible Structure ◽

Fully Integrated ◽

Flexible Materials ◽

Alternative Routes

Solar cells are an option for powering active electronics on textiles, but should be fully integrated to avoid compromising the flexibility and handle of the basic fabric. Photovoltaic (PV) cells conventionally use rigid silicon wafers but there are also thin-film options, although some are sensitive to moisture and oxygen, and others require processing temperatures outside the range of most flexible materials. The coating on textiles is also influenced by the fabric’s texture, elasticity, and surface roughness. The demands of a flexible structure affect the choice of the other parts of PV cells, namely their electrical contacts and any encapsulation layers. The two alternative routes to a textile PV design are—(i) coat the fabric with successive layers needed to make a sandwich device, or (ii) coat individual yarns with these layers and then process them into a fabric, e.g., by weaving.

Download Full-text