Several key organizations are responsible for publishing and maintaining the standards that govern the tool steel industry. Understanding these bodies helps you navigate material specifications and certifications effectively. 

ASTM (American Society for Testing and Materials) 

• ASTM International is one of the most influential standards organizations globally. For tool steels, the primary specification is ASTM A681 – Standard Specification for Tool Steels Alloy. This document provides a comprehensive framework for classifying tool steels based on their intended application and chemical composition. ASTM organizes tool steels into distinct groups, such as cold-work, hot-work, and high-speed steels, assigning them alphanumeric designators that are widely recognized in North America and beyond. 

AISI (American Iron & Steel Institute) 

• While the AISI no longer maintains tool steel standards directly (this role has largely been absorbed by ASTM), its classic grading system remains foundational to the industry. The AISI-SAE system established the familiar grade designations like O1 (oil-hardening), D2 (high-carbon, high-chromium), A2 (air-hardening), and H13 (hot-work). These designations are still used universally by engineers and procurement managers to specify tool steel types. 

DIN (Germany) / EN (Europe) 

• In Europe, the German Institute for Standardization (DIN) and the broader European Standards (EN) are the primary reference points. These standards often use a numeric system known as the Werkstoff-Nummer (W-Nr.), such as 1.2379 for D2 tool steel or 1.2344 for H13. This system provides a precise and language-independent way to identify steel grades. European standards are known for their rigorous requirements, making DIN/EN certification a mark of quality. 

ISO (International Organization for Standardization) 

• ISO works to harmonize standards from different countries to facilitate global trade and technical collaboration. ISO 4957:2018 is the key international standard for tool steels. It classifies grades based on their chemical composition and application, creating a bridge between various national standards like ASTM and DIN. ISO standards help ensure that materials are truly interchangeable on a global scale. 

JIS (Japan Industrial Standards) 

• JIS standards are developed by the Japanese Industrial Standards Committee and are prevalent in Asia. JIS provides its own set of grade designations, such as SKD11 (equivalent to D2/1.2379) and SKD61 (equivalent to H13/1.2344). For companies operating in or sourcing from Asian markets, familiarity with JIS is essential for verifying material equivalency. 

BS (British Standards) 

• British Standards, designated with a "BS" prefix, were once common in the UK and Commonwealth countries. While many have been superseded by EN standards, some legacy grades like BD2 or BH13 are still referenced. Understanding these historical classifications can be useful when dealing with older equipment drawings or specifications.