Gray iron castings for strength and value

Why gray iron for castings

Gray iron is a proven solution for applications where strength, thermal control, and vibration damping matter, without adding cost or complexity. It’s ideal for high-volume production where repeatability and ease of machining are priorities.

Cost-effective for large production runs

Strong compressive strength for structural reliability

Good machinability for tight tolerances

Excellent vibration damping for noise and shock control

Where gray iron is used

Gray iron is widely used in heavy-duty applications that demand durability and stability. Milson supplies gray iron castings for a broad range of industrial components.

Agricultural equipment parts
Pump bodies and impellers
Machine tool frames

Typical properties (values vary by grade and specification):

Compressive strength: 100–200 ksi
Tensile strength: 20–60 ksi
Hardness: 150–250 BHN
Thermal conductivity: High — effective for heat dissipation
Machinability: Excellent
Vibration damping: Superior for noise and shock control

ASTM A48 (Gray Iron) mechanical properties

Grade	Tensile Strength, min (KSI)
Class 20	20
Class 25	25
Class 30	30
Class 35	35
Class 40	40
Class 45	45
Class 50	50
Class 55	55
Class 60	60

Full-service gray iron casting, start to finish

From prototyping to production, Milson offers complete gray iron casting services under one roof. We combine modern foundry practices with deep material knowledge to deliver parts that meet tight deadlines and demanding specs.