What is Carbon Steel Investment?

Carbon steel investment casting is made through Sodium Silicate Lost Wax Casting Process. Due to mechanical properties, it might need surface treatment like painting, zinc plating to improve anti-corrosion and hot treatment for strengthening hardness.

Because of the carbon content, carbon steel has high strength and enough toughness, low notch sensitivity, good low-temperature toughness, aging sensitivity, fatigue resistance, and welding performance.


Carbon steels can be classified into 3 different types:

Low-carbon steels(< 0.20% C):

It is softer and more malleable than other types. It may require heat treatment to give high surface hardness with abrasion resistance and good core ductility.

UTS 400 – 450N/mm2.  Elongation 15%.  HB 120-180

Medium-carbon steels(0.20 to 0.50% C):

It is more durable, pliable, and stronger, compared to low-carbon steels. The tensile strengths has good ductility and shock resistance, readily machined in the softened condition.

UTS 700 – 850N/mm2.  Elongation 11%.  HB 200-300

High-carbon steels(> 0.50% C):

It is strong and has a good shape memory. The alloy steel for high tensile applications is subject to wear and abrasion and is suitable for heavy-duty applications as well.

UTS 800 – 1000N/mm2.  Elongation 5-8%.  HB 250-400