ISO 16468:2025

Overview

ISO 16468:2025 - Investment castings (steel, nickel alloys and cobalt alloys) - General technical requirements - defines the technical and inspection requirements for parts produced by the investment (lost‑wax) casting process in steel, nickel and cobalt alloy families. The third edition updates the 2015 version and sets requirements that become an integral part of any material specification; where conflicts occur, ISO 16468:2025 takes precedence.

Keywords: ISO 16468:2025, investment castings, steel castings, nickel alloy castings, cobalt alloy castings, general technical requirements.

Key topics and technical requirements

• Materials and manufacture
  • Primary heats are to be produced by electric furnace routes, with optional refining (e.g., AOD, VOD, VIM) unless otherwise agreed.
  • Sub‑heats (remelts) are made by induction furnaces, with or without atmosphere protection; limitations on re‑melting of revert material are specified.
• Inspection and testing
  • General inspection follows ISO 4990; sampling rules specify how chemical and mechanical test samples relate to primary heats and sub‑heats.
  • Test‑block options and specimen locations are illustrated (Figure 1) and guidance is provided for mechanical test sampling.
• Non‑destructive examination (NDE) and supplementary requirements
  • A suite of supplementary options can be specified in orders: magnetic particle, liquid penetrant, radiographic, ultrasonic inspection, weld preparation inspection, impact testing, hardness testing (Brinell, Rockwell, Vickers), ferrite determination in duplex/austenitic steels, and more.
• Quality, cleaning and finishing
  • Cleaning/dressing requirements ensure surface conditions are sufficient for acceptance checks; visual acceptance standards are to be agreed (ISO 11971 may be used).
  • Production welding must comply with ISO 11970.
• Additional provisions
  • Rules for retests, marking, decarburization concerns, metallurgical cleanliness, sampling frequencies and documentation are included or referenced.

Practical applications and users

ISO 16468:2025 is used by:

• Foundries and investment‑casting manufacturers specifying process, melting and remelt practices.
• Quality, inspection and metallurgy engineers setting acceptance criteria and sampling plans.
• Purchasers and procurement teams who include casting technical requirements in contracts.
• NDE technicians and welding engineers applying inspection, welding and repair requirements.
• Industries that rely on high‑integrity precision cast components - e.g., aerospace, power generation, oil & gas, medical devices and specialist engineering - where controlled metallurgical and inspection practices are critical.

Related standards

Normative and referenced standards commonly used with ISO 16468:2025 include:

• ISO 4990 (general technical delivery requirements for steel castings)
• ISO 4992‑1 / 4992‑2 (ultrasonic testing)
• ISO 4993 (radiographic testing)
• ISO 4986 / ISO 4987 (magnetic particle / liquid penetrant testing)
• ISO 6506‑1, ISO 6507‑1, ISO 6508‑1 (hardness tests)
• ISO 10474 (inspection documents) and ISO 11970 (welding procedure specification)
• ISO 13520 (ferrite determination in austenitic stainless steel castings)

Use ISO 16468:2025 when specifying investment‑casting technical requirements to ensure consistent metallurgical practice, sampling, inspection and acceptance criteria for steel, nickel and cobalt alloy parts.