Electrostatic discharge materials

The expansion of the areas of application for carbon fibers is stimulated by their attractive properties, not found in other materials, such as strength, electrical conductivity, stability on exposure to reactive media, low density, low-to-negative coefficient of thermal expansion, and resistance to shock heating. The most representative applications of carbon fibers and element carbon fibers are as sorption materials, electrostatic discharge materials, catalysts, and reinforcement materials in composites. 

During the selection of the proper materials to be used for protection, several characteristics of each material would be rated to help narrow the decision. The minimum characteristics that should be evaluated for these materials are ability to withstand environmental and plant produced radiation, coefficient of thermal expansion, density, electrical resistivity and conductance to control electrostatic discharge, material chemistry ar d composition, operational temperature range, resilience, specific heat, strength, stiffness, thermal conductivity, thermal radiation absorptivity, thermal radiation emissivity, the ability to fasten the material to the support structure and/or the components themselves, and the compatibility between the protecting material and material to which it would be fastened... 

Sensitivity to Electrostatic Discharge. Thru 100 mesh material, confined 6.0 joules, unconfmed 0.025 joules (Ref 10)... 

Pai Vernekar and Patil [264] and Shanguan et al. [265] reported synthesis and characterization of NHN. Its important attributes are (i) easily prepared from cheap and readily available raw materials (ii) hydrolytically and thermally stable (iii) less sensitive to impact (h50% 84cm), friction (insensitive up to ION) and electrostatic discharge but at the same time, sensitive to flash, flame and hot wire ... 

Highest Electrostatic Discharge Energy at 5000 Volts for Zero Ignition Probability for Representative Materials... 

Results of tests giving the highest electrostatic discharge energies at 5000 volts for zero ignition propagation for various materials, are given in Table E6, which is complied from table 1 of Ref 4 and Table 3 of Ref 13... 

Previously reported [2] as a non-melting solid exploding on attempted purification, this proved a very shock sensitive (40 kg/cm) solid of m.p. 150°C. Less sensitive to electrostatic discharge and friction. Methods of explosibility testing for very small quantities of very sensitive materials are described [1]. 

As an initial step, the reports of l80 in-process accidents were viewed. A sianmary of the type of information obtained is shown in Fig 22. The process operation and the probable causative stimuli which led to the accident are given in terms of the number of accidents and the percentage of the total number. Thus the most probable causes of an accident were identified in an accident analysis. The causes varied by process operation and material type. However friction, impact, electrostatic discharge (ESD), and heating were the most commonly identified causative stimuli. 

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