ASTM F75-23 PDF

Overview

ASTM F75-23: Standard Specification for Cobalt-28 Chromium-6 Molybdenum Alloy Castings and Casting Alloy for Surgical Implants (UNS R30075) establishes critical requirements for unfinished investment castings and casting alloys used in the manufacture of surgical implants. Developed by ASTM International, this standard applies to the materials-specifically in forms like shot, bar, or ingots-prior to their fabrication into finished medical devices. It details chemical composition, mechanical, and metallurgical criteria, ensuring that alloys intended for surgical implant production achieve the consistent quality and performance required for medical applications.

This specification supports regulatory compliance and quality assurance in the medical device industry, serving as a benchmark for suppliers, manufacturers, and auditors involved in the surgical implants supply chain.

Key Topics

• Scope of Coverage

  • Applies to cobalt-28 chromium-6 molybdenum (Co-Cr-Mo) alloy castings and casting alloys for surgical implant manufacturing
  • Does not address finished implants or fabricated end-use devices

• Material and Manufacturing Requirements

  • Strict conformance to specified chemical composition, including cobalt, chromium, and molybdenum balance
  • Control of residual elements and prohibition of unspecified intentional additions
  • Welding for repair is allowed under stringent procedures, performed before any final thermal processing and using matching alloy filler

• Mechanical Properties

  • Ultimate tensile strength, yield strength, elongation, and reduction of area must be verified for each master heat
  • Testing follows ASTM E8/E8M for tension, with clear acceptance and retesting protocols to ensure uniform quality

• Quality Control and Testing

  • Product and casting alloy samples must undergo:
    • Chemical analysis for conformity
    • Liquid penetrant examination
    • Radiographic (X-ray) testing
    • Metallographic inspection
    • Rockwell hardness testing (for informational purposes)
  • Sampling and acceptance criteria for special tests to be agreed upon between supplier and purchaser

• Unit Selection and Certification

  • Values reported in either SI or inch-pound units as chosen by the purchaser
  • Certification required, providing documentation that material meets all specified criteria

• Quality Management

  • Suppliers must maintain a recognized quality management system such as ISO 9001 or ISO 13485
  • Purchasers have the right to audit producers for compliance

Applications

This ASTM standard is essential in the manufacture of raw materials for surgical implants, providing foundational requirements for materials used in components such as:

• Orthopedic joint prostheses (e.g., hip and knee implants)
• Dental implants
• Spinal implants and hardware
• Trauma fixation devices

The cobalt-chromium-molybdenum alloy (UNS R30075) covered by ASTM F75-23 is valued for its biocompatibility, corrosion resistance, high strength, and proven track record in medical use. The specification ensures these qualities are realized consistently throughout the production process. While the standard does not address finished medical devices, it plays a crucial role in the upstream quality assurance of implantable materials, providing a recognized basis for traceability and regulatory acceptance.

Related Standards

ASTM F75-23 references and aligns with a range of other national and international standards, enhancing its relevance throughout the surgical implant supply chain:

• ASTM A957/A957M – General requirements for investment castings
• ASTM E8/E8M – Methods for tension testing of metallic materials
• ASTM E18 – Rockwell hardness testing procedures
• ASTM E165/E165M, F601, F629 – Test methods for penetrant and radiographic inspection of metallic implants
• ISO 5832-4 – Equivalent international standard for Co-Cr-Mo casting alloy
• ISO 9001 / ISO 13485 – Quality management system requirements for manufacturers in the medical device sector

By adhering to the ASTM F75-23 specification, manufacturers can demonstrate compliance with regulatory expectations, support quality documentation for audits, and reinforce market acceptance of their surgical implant materials worldwide.

Keywords: ASTM F75-23, cobalt-chromium-molybdenum alloy, UNS R30075, surgical implant materials, investment casting, medical device manufacturing, biocompatibility, quality management, orthopedic implants.