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The authors discuss the effective design of metallic-contact micromechanical switches. Suggestions for managing heat dissipation include design and usage of heat sinks, covering switch contact electrodes with high thermal conductivity metals, and better utilization of gold's electrical properties.

A series of studies were conducted to investigate changes resulting from contact resistance of several common engine compartment electrical connector contact materials at 150 degrees centigrade. The contact materials studied were 0.2% Co hard gold plate, diffuse gold alloy, tin plated copper alloy and silver plated copper alloy. The tests focused on the wear and oxidation mechanisms. Experimental methodology and results are discussed.

An experiment presents results from a test system design which aimed to recreate the existing limiting operation of a miniature circuit breaker. The results presented were obtained in conditions where opening contacts were considered in a flexible test apparatus. They further the understanding of the complex arc motion mechanisms occurring in miniature current limiting circuit breakers. One of the findings show that a high contact velocity is a significant but not essential parameter in providing arc root mobility.

A study was conducted to investigate the possibility of building self-assembled monolayers on appropriately prepared nickel surfaces for low level electrical contact applications. The experiment presents preliminary results pertaining to new, self-assembled protecting organic monolayers of alkenethiols on nickel substrates. Among other findings, it was shown that CH3-(CH2)11-SH layers on reduced nickel exhibit outstanding friction behavior.

A study was conducted to develop an analytical fretting degradation model to address some of the major concerns relating to accelerated testing of connector contacts made with copper alloys and tin or tin-lead plating. The failure mechanisms considered in the investigation address the long-term aging processes of contact materials. Among other results, it was found that algorithms could be developed to simulate different aging mechanisms for a given set of test or field conditions.

The most significant failure mechanism for tin plated contacts is what is called fretting corrosion, which has been the focus of numerous studies. A study discusses the phenomenon of fretting corrosion which leads to contact failures and proposes a formula which determines the limit from where a slip will begin to occur in connector assemblies. The use of lubrication as an alternative method to inhibit the increase of contact resistance is also evaluated.

A study evaluates the the influence of factors such as mechanical load, electrical current and alpha-spot temperature on the conductance properties of stationary alpha-spots in a bulk electrical junction or interface. The effect of mechanisms such as oxidation that reduce contact area may be offset by mechanisms which promote alpha-spot growth in stationary contacts. One such significant alpha-spot growth mechanism is discussed.

A study was conducted to investigate a simple corrective action which could in favorable cases restore connectors with tin-lead finishes and those with tin-lead mated to gold. Modeling experiments will demonstrate that lubricants, which when applied to new connector contacts increase their life, can restore failed tin-lead and gold-mated-to-tin-lead contacts especially when the fretting degree is not very quick. Experimental procedure, materials and conclusions are presented.

Studies were conducted in silver metal oxide contacts on a purposed built apparatus to investigate the magnitude of contact erosion under opening or break operations. Ag/SnO2 and Ag/CdO contact rivets were evaluated with alternating current of as much as 30 A rms, contacts opened at particular point-on-wave and at different opening velocities between 0.1-0.8 ms-1. Experimental methodology, findings and conclusions are discussed.