【国外标准】 Standard Specification for Nuclear-Grade Boron Carbide Powder

This specification defines the chemical and physical requirements for boron carbide powder intended for a variety of nuclear applications. The powder shall be classified as: Type 1; Type 2; and Type 3. The material shall conform to the chemical composition requirements prescribed. Quality control tests, acceptance tests, referee tests, and retention of archive samples by the seller shall be performed to conform to the specified requirements.1.1 This specification defines the chemical and physical requirements for boron carbide powder intended for a variety of nuclear applications. Because each application has a different need for impurity and boron requirements, three different chemical compositions of powder are specified. In using this specification, it is necessary to dictate which type of powder is intended to be used. In general, the intended applications for the various powder types are as follows:1.1.1 Type 1—For use as particulate material in nuclear reactor core applications.1.1.2 Type 2—Powder that will be further processed into a fabricated shape for use in a nuclear reactor core or used in non-core applications when the powder directly or indirectly may cause adverse effects on structural components, such as halide stress corrosion of stainless steel.1.1.3 Type 3—Powder that will be used for non-core applications or special in-core applications.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 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.