ASTM B671-81(2021) PDF

Overview

ASTM B671-81(2021) - Standard Specification for Refined Iridium defines the requirements for iridium metal in refined forms, specifically as sponge and powder. Established by ASTM International, this specification sets standards for chemical composition, grading, and quality control of refined iridium materials. Iridium's unique physical and chemical properties make it essential in specialized industrial and technological applications, where high purity and strict control over trace elements are critical.

Key Topics

• Grades & Composition: The standard specifies two iridium grades:

  • Grade 99.80 (UNS PO6100): Minimum iridium content of 99.80%
  • Grade 99.90: Minimum iridium content of 99.90%

• Impurity Limits: Both grades require strict limits on trace elements such as rhodium, platinum, palladium, ruthenium, lead, silicon, tin, zinc, arsenic, bismuth, cadmium, iron, silver, gold, copper, nickel, and chromium. These requirements help ensure the refined iridium's integrity and suitability for critical use cases.

• Production Methods: Refined iridium may be produced by any process that yields a product capable of meeting the chemical requirements. Manufacturers must inform buyers of the refining method upon request.

• Sampling and Testing: Sampling procedures are crucial due to the high value of iridium material. The standard covers sampling by lot for both sponge and powder forms, and mandates mutually agreed-upon sampling and analytical methods between purchaser and manufacturer.

• Product Marking: Containers holding iridium must be clearly labeled with the material grade, lot number, and precise weight, ensuring traceability and quality assurance in supply chains.

Applications

• Electronics and Electrical Contacts: Refined iridium powder and sponge are used in manufacturing electrical contacts and spark plugs, where exceptional corrosion resistance and electrical conductivity are required.

• Chemical Catalysts: Iridium's chemical inertness makes it valuable in the production of catalysts for chemical reactions and in electrochemical applications.

• High-Temperature Equipment: Components exposed to extreme temperatures, such as crucibles or furnace parts, utilize refined iridium for its outstanding stability and resistance to oxidation.

• Medical Devices: In medical technology, iridium is used in electrodes for cardiac devices and other medical instrumentation where precision and biocompatibility are essential.

• Research and Metrology: Due to its purity, refined iridium is also critical in metrology standards and advanced scientific research.

Related Standards

• ASTM E29 - Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications: Referenced for methods of rounding analytical results when determining compliance with ASTM B671-81(2021).

• Other Precious Metal Specifications: Organizations and manufacturers may also reference standards for platinum, palladium, and rhodium, depending on application requirements.

• ISO and Trade Compliance: ASTM B671-81(2021) aligns with international standardization principles in accordance with World Trade Organization (WTO) Technical Barriers to Trade (TBT) Committee guidelines.

Practical Value

The specification ensures quality assurance and uniformity of refined iridium for global markets. Compliance with ASTM B671-81(2021) enables manufacturers, suppliers, and end-users to specify, procure, and receive iridium materials that meet stringent purity, composition, and labeling criteria vital for high-performance technologies. Supply chain consistency and traceability are enhanced, minimizing risks of contamination and ensuring reliable functionality in demanding applications.

Keywords: ASTM B671, refined iridium, iridium powder, iridium sponge, purity, chemical composition, precious metals, standards compliance, industrial applications, iridium specification.