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AISI 4042
Category Steel
Class Alloy steel
Type Standard
Common Names Molybdenum steel
Designations  United States: ASTM A322 , ASTM A331 , ASTM A519 , SAE J404 , SAE J412 , SAE J770 , UNS G40420

Composition

ElementWeight %
C  0.40-0.45 
Mn  0.70-0.90 
P  0.035 (max) 
S  0.04 (max) 
Si  0.15-0.30 
Mo  0.20-0.30 

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  
Tensile Strength (Mpa) 1800  25  oil quenched, fine grained, tempered at 205°C  more
Yield Strength (Mpa) 1662 
Elongation (%) 12 
Reduction in Area (%) 37 
Hardness (HB) 516  25  oil quenched, fine grained, tempered at 205°C more
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3D Scanners

A white paper to assist in the evaluation of 3D scanning hardware solutions.

Selecting the Right 3D Printer

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

STEM Career Outlook

Wages, employment opportunities, and growth projections for STEM jobs.

Metal 3D Printing Design Guide

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