Metal Alloys
Alloy Home
Steels
Tool Steels
General Information
Properties
Tool Steel Types
High-Speed
Hot-Work
Cold-Work
Shock-Resistant
Mold
Special-Purpose
Water-Hardening
Tool Steel List
AISI Ax
AISI Dx
AISI Hx
AISI Lx
AISI Mx
AISI Ox
AISI Px
AISI Sx
AISI Tx
AISI Wx
Specific Tool Steel
General Information
Resources
Bibliography
Laser Focus World

Semiconductors, medical equipment, lasers, optics and aviation and aerospace.

Negotiate Your Salary

Learn the best principles to negotiate the salary you deserve!

Wind Systems

Towers, turbines, gearboxes; processes for shaping and finishing component parts.

Metal 3D Printing Design Guide

Direct Metal Laser Sintering (DMLS) 3D printing for parts with reduced cost and little waste.

more free magazines
 
AISI A9
Category Steel
Class Tool steel
Type Air-hardening medium-alloy cold work steel
Designations  United States: ASTM A681 , FED QQ-T-570 , UNS T30109

Composition
ElementWeight %
C  0.45-0.55 
Mn  0.50 
Si  0.95-1.15 
Cr  4.75-5.50 
Ni  1.25-1.75 
Mo  1.30-1.80 
V  0.80-1.40 
Cu  0.25 
P  0.03 
S  0.03 

Mechanical Properties
Properties Conditions 
T (°C)Treatment
Density (×1000 kg/m3) 7.78 25  
Poisson's Ratio 0.27-0.30 25  
Elastic Modulus (GPa) 190-210 25  

Thermal Properties
Properties Conditions 
T (°C)Treatment
Thermal Expansion (10-6/ºC) 12  20-425 more  
Glossary