AISI 1075 Carbon Steel Technical Overview

AISI 1075 carbon steel is a high-carbon steel grade valued for its specific properties, which can be achieved through heat treatment. Understanding its composition and characteristics is key to leveraging its application capabilities.

1. Chemical Composition

1075 steel falls squarely into the high-carbon steel category, which typically encompasses steels with carbon content ranging from 0.60% to 2.40%.

The standard chemical composition for 1075 grade steel, identified by UNS Number G10750 and specified under SAE J403, is as follows:

• Carbon (C): 0.70% – 0.80%
• Manganese (Mn): 0.50% – 0.80%
• Phosphorus (P): 0.040% maximum
• Sulfur (S): 0.050% maximum

Note: Related carbon tool steel specifications may list tighter maximum limits for Phosphorus and Sulfur (e.g., 0.03%).

2. Hardness

The significant carbon content allows 1075 steel to achieve substantial hardness levels when properly hardened. Steels with carbon levels around this range (approx. 0.83%) can reach hardness values up to Rockwell C 67 (RC 67). This high hardness potential makes 1075 suitable for applications demanding excellent wear resistance.

3. Heat Treatment

Its composition makes 1075 sensitive to thermal processing. It is a candidate for various hardening techniques, including induction hardening, particularly for applications requiring localized hardness on the steel surface. Careful control during heat treatment is necessary to achieve the desired properties.

4. Machinability and Applications

The high hardness achievable with 1075 steel makes it a common choice for tooling and components requiring durability.

Regarding machining, reference data suggests specific parameters for operations like turning with high-speed steel (HSS) tools. For AISI 1075, a suggested speed is 30 surface feet per minute (SFM), with a feed rate of 0.0115 inches per revolution (ipr) and a depth of cut of 0.075 inches for medium operations.

5. Equivalent Steel Grade

For international comparison, a closely corresponding European standard is available:

• EN Standard: EN 10132-4:2000
• Grade: C75S
• Steel Number: 1.1248