【国外标准】 Standard Guide for Preparing Specifications for Miniature Brushes of Composite Materials for Sliding Electric Contacts

This guide defines the criteria for composition, properties, and other requirements for miniature brushes of composite materials containing a matrix of one or more conducting metallic elements or alloys and one or more lubricating lamellar solids intended for sliding electric contacts. Each constituent of the material should be listed individually by weight percent including tolerances using any analytical technique while the apparent density for the material should be defined using the measurement and weight method. The resistivity; Rockwell superficial hardness, transverse strength, and shear strength; and microstructural properties such as cracks and defects should also be defined and should conform to the required electrical, mechanical, and structural properties of the brush materials.1.1 This guide defines the criteria for composition, properties, and other requirements for brushes containing a matrix of one or more conducting metallic elements or alloys and one or more lubricating lamellar solids.1.2 The resulting specification is intended for use where the size (for example, 5 mm by 3 mm by 2 mm), shape, or other factors preclude the determination of properties on specimens of the bulk material from which individual brushes are made.1.3 The requirements recommended herein have been found to be desirable for most brush material composites. Care must be taken in preparing a specification for a pre-existing material that imposition of one or more provisions herein does not alter the material or its performance.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to become familiar with all hazards including those identified in the appropriate Safety Data Sheet (SDS) for this product/material as provided by the manufacturer, to establish appropriate safety, health, and environmental practices, and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.