D2 vs A2 vs O1 vs H13 vs P20 Tool Steel: Complete Selection Guide

Introduction 

Tool steels are specialized alloy steels designed to withstand extreme working conditions such as abrasion, heavy loads, and high temperatures. These materials are widely used for manufacturing dies, molds, punches, cutting tools, and industrial tooling components. 

Selecting the right tool steel grade is essential for improving tool life, manufacturing efficiency, and dimensional stability. Engineers typically compare grades such as D2, A2, O1, H13, and P20 to determine which material performs best for a specific application. 

This guide explains the properties, composition, and applications of these commonly used tool steels. 

For the complete engineering guide, visit: 
https://niftyalloys.com/blogs/tool-steel-guide 

Chemical Composition Comparison 

Tool steels obtain their mechanical strength and wear resistance from alloying elements such as carbon, chromium, molybdenum, and vanadium. 

Grade	Carbon	Chromium	Molybdenum	Vanadium	Feature
O1	0.9–1.2%	~0.5%	Small	Trace	Oil hardening
A2	~1.0%	~5%	~1%	0.25%	Air hardening
D2	1.4–1.6%	11–13%	~1%	~1%	High wear resistance
H13	0.32–0.45%	4.8–5.5%	1.2%	0.8–1.2%	Hot work steel
P20	0.28–0.40%	1.4–2.0%	0.3–0.5%	Trace	Mold steel

 

These alloying elements significantly influence the performance of each grade. 

For example: 

• D2 tool steel contains high chromium carbides that provide excellent wear resistance. 
• H13 tool steel contains molybdenum and vanadium that enhance performance at elevated temperatures. 

Mechanical Properties of Tool Steel Grades 

 

Grade	Hardness (HRC)	Key Advantage
O1	58–62	Tough general tooling
A2	57–62	Dimensional stability
D2	55–62	High wear resistance
H13	46–52	Heat resistance
P20	28–34	Pre-hardened mold steel

 

Each grade offers different mechanical advantages depending on the application. 

 

Typical Applications 

O1 Tool Steel 

• Cutting tools 
• Punches 
• Gauges 

A2 Tool Steel 

• Blanking dies 
• Forming dies 
• Shear blades 

D2 Tool Steel 

• Stamping dies 
• Thread rolling dies 
• Metal forming tools 

H13 Tool Steel 

• Die casting molds 
• Hot forging dies 
• Extrusion tooling 

P20 Tool Steel 

• Plastic injection molds 
• Mold bases 

Choosing the Right Tool Steel 

When selecting tool steel, engineers must consider: 

• Wear resistance requirements 
• Operating temperature 
• Toughness and impact resistance 
• Dimensional stability during heat treatment 

General selection guidelines include: 

• Use D2 tool steel for high wear resistance. 
• Use A2 tool steel for precision tooling. 
• Use O1 tool steel for general-purpose tools. 
• Use H13 tool steel for hot working applications. 
• Use P20 tool steel for mold manufacturing. 

Learn More About Tool Steel 

To explore full specifications, stock sizes, and supply availability, read the complete guide: 

https://niftyalloys.com/blogs/tool-steel-guide 

You can also explore individual grades: 

• D2 Tool Steel 
• A2 Tool Steel 
• O1 Tool Steel 
• H13 Tool Steel 
• P20 Tool Steel