ISO TR 945-3-2016 PDF

Full title and description

Microstructure of cast irons — Part 3: Matrix structures. This technical report defines and illustrates the matrix structures found in various cast‑iron types, giving designations, descriptive text and reference photomicrographs to support consistent metallographic evaluation and specification.

Abstract

ISO/TR 945-3:2016 provides standardized designations, descriptions and reference micrographs of matrix (metallic phase) structures in cast irons. It covers commonly used cast‑iron families (grey, spheroidal/ductile, austenitic, malleable, compacted/vermicular, ausferritic spheroidal and abrasion‑resistant cast irons), specifies the etching convention used for the reference images (2 % nitric acid in ethanol, Nital, unless otherwise stated) and supplies visual references to improve communication between foundries, purchasers and laboratories.

General information

• Status: Published (confirmed international technical report).
• Publication date: 2016-05 (first edition, 2016).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 77.080.10 (Irons).
• Edition / version: Edition 1 (2016).
• Number of pages: ISO lists 42 pages for the official publication; some distributors report 50–52 pages in their product listings (typical variation reflects different preliminaries/printing formats).

Scope

ISO/TR 945-3:2016 applies to the classification and visual description of matrix structures in cast irons and is intended to be used alongside the other parts of the ISO 945/945‑TR series that address graphite morphology and related metallographic features. The report is intended for use with metallographic specimens prepared and etched as specified (commonly with 2 % Nital) and provides reference micrographs and explanatory text for matrix types encountered in grey, spheroidal, austenitic, malleable, compacted (vermicular), ausferritic spheroidal and abrasion‑resistant cast irons.

Key topics and requirements

• Standardized designations and descriptive definitions for matrix structures (e.g., ferritic, pearlitic, bainitic, martensitic, austenitic, ausferritic variants).
• Reference photomicrographs illustrating typical microstructures and aiding visual comparison and acceptance criteria.
• Specimen preparation and etching convention for the reference images (2 % nitric acid in ethanol, Nital, unless otherwise noted).
• Tables correlating matrix types to specific cast‑iron families (grey, SG/ductile, austenitic, malleable, compacted/vermicular, ausferritic SG, abrasion‑resistant).
• Guidance to support quality control, metallography, failure analysis and specification wording between suppliers and purchasers.

Typical use and users

This technical report is used by foundry metallurgists, quality and inspection engineers, materials and design engineers, failure‑analysis laboratories and research groups. Typical applications include acceptance criteria for castings, metallographic classification during quality control, process and heat‑treatment development (e.g., austempering to achieve ausferritic matrices), and clear visual communication of matrix requirements in procurement documents.

Related standards

ISO/TR 945‑3 is part of the ISO 945 family and is typically used with other documents addressing graphite classification and cast‑iron properties (for example ISO 945 parts and technical reports). Standards commonly referenced alongside it include ISO 945 (graphite classification), ISO 185, ISO 1083, ISO 2892 and ISO 5922, which cover related material designations, casting definitions and testing/inspection practices.

Keywords

cast iron, microstructure, matrix structure, metallography, reference photomicrographs, Nital etch, ferrite, pearlite, bainite, martensite, ausferrite, spheroidal graphite, grey iron, vermicular/compacted graphite.

FAQ

Q: What is this standard?

A: ISO/TR 945-3:2016 is an ISO technical report titled "Microstructure of cast irons — Part 3: Matrix structures" that provides standardized names, descriptions and reference micrographs for the metallic matrix structures found in various cast‑iron families.

Q: What does it cover?

A: It covers designation, descriptive text and reference photomicrographs of matrix structures (ferritic, pearlitic, bainitic, martensitic, austenitic, ausferritic variants, etc.) for a range of cast‑iron types and specifies the etching convention used for the reference images (commonly 2 % Nital).

Q: Who typically uses it?

A: Foundry metallurgists, quality inspectors, materials engineers, failure‑analysis labs, researchers and purchasers specifying cast‑iron components use this report to ensure consistent metallographic classification and communication.

Q: Is it current or superseded?

A: The document was published in 2016 as the first edition. As a technical report it is subject to periodic review; users should check the issuing body for the current status or any confirmed revisions. (ISO indicates the 2016 edition; distributors list the same 2016 publication).

Q: Is it part of a series?

A: Yes — it belongs to the ISO 945 family (parts and related technical reports) that collectively address graphite morphology and microstructural classification of cast irons.

Q: What are the key keywords?

A: Cast iron, matrix structure, microstructure, metallography, photomicrograph, Nital, ferrite, pearlite, bainite, martensite, ausferrite, spheroidal graphite.