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CNC Machining Design Guide

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Metal 3D Printing Design Guide

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

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AISI A4
Category Steel
Class Tool steel
Type Air-hardening medium-alloy cold work steel
Designations  United States: ASTM A681 , FED QQ-T-570 , UNS T30104

Composition
ElementWeight %
C  0.95-1.05 
Mn  1.80-2.20 
Si  0.50 
Cr  0.90-2.20 
Ni  0.30 
Mo  0.90-1.40 
Cu  0.25 
P  0.03 
S  0.03 

Mechanical Properties
Properties Conditions 
T (°C)Treatment
Density (×1000 kg/m3) 7.7-8.03 25  
Poisson's Ratio 0.27-0.30 25  
Elastic Modulus (GPa) 190-210 25  
Glossary
CNC Machining Design Guide

Optimize your designs, reduce machining time, and lower your costs.

Essentials of Manufacturing

Information, coverage of important developments and expert commentary in manufacturing.

Selecting the Right 3D Printer

Discover how to choose the right 3D printer for your needs and the key performance attributes to consider.

Metal 3D Printing Design Guide

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