Comprehensive Guide to SAE AISI 1117 Carbon Steel

Imagine a material that combines exceptional machinability with impressive mechanical properties, making it a favorite in the world of manufacturing and engineering. This is exactly what SAE AISI 1117 carbon steel offers. Known for its versatility and efficiency, this steel variant is widely utilized in the production of automotive parts, valves, pumps, and general engineering components.

In this comprehensive guide, you will delve into the intricate chemical composition of SAE AISI 1117, understanding how elements like carbon, manganese, and sulfur contribute to its unique properties. You’ll explore its mechanical strengths, such as tensile and yield strength, hardness, and impact resistance, and discover why it stands out in machining and forging processes.

Ready to uncover the advantages and practical applications of SAE AISI 1117 carbon steel? Let’s dive in and explore how this remarkable material can enhance your projects and deliver long-term benefits.

Overview of SAE AISI 1117 Carbon Steel

SAE AISI 1117 carbon steel is modified with sulfur to enhance its machinability. Designated as UNS G11170, this steel grade is part of the AISI-SAE 1100 series, known for its superior mechanical properties and ease of processing compared to standard low-carbon steels.

SAE AISI 1117 carbon steel holds significant importance in manufacturing and engineering due to its unique combination of properties. Its enhanced machinability allows for efficient high-volume production of precision parts, reducing tool wear and machining time. The steel’s balanced composition also provides good strength, making it suitable for components that require both durability and precision. This combination of enhanced machinability and balanced mechanical properties ensures that SAE AISI 1117 is a cost-effective choice for producing high-quality parts with fewer defects.

Key Benefits

1. Enhanced Machinability: The sulfur and manganese additions facilitate smoother cutting operations and extend tool life.
2. Strength and Hardness: The carbon and manganese content in SAE AISI 1117 ensures adequate tensile strength and hardness, making it suitable for parts subjected to mechanical stress.
3. Versatility: This steel can undergo various manufacturing processes such as hot rolling, cold finishing, and forging, making it adaptable to different production needs.
4. Cost-Effectiveness: The efficiency in machining and the ability to produce high-quality parts with fewer defects contribute to overall cost savings in production.

SAE AISI 1117 carbon steel is commonly used for applications requiring precise machining and reliable performance. Typical uses include:

• Automotive Components: Ideal for manufacturing gears, shafts, and other parts that require carburization and high dimensional accuracy.
• Valves and Pumps: The material’s wear resistance and machinability make it suitable for components that must withstand continuous operation and fluid dynamics.
• General Engineering Parts: Its balanced properties make it a reliable choice for various engineering applications where both strength and precision are required.

Chemical Composition

The chemical composition of SAE AISI 1117 is carefully formulated to enhance its machinability and mechanical properties:

• Carbon: 0.14–0.20%
• Manganese: 1.00–1.30%
• Sulfur: 0.08–0.13%
• Phosphorus: Up to 0.04%
• Iron: Balance

This precise alloying ensures that the steel maintains its desirable characteristics across different applications.

Mechanical Properties

SAE AISI 1117 exhibits mechanical properties that make it suitable for a wide range of industrial uses:

• Tensile Strength: Approximately 430–480 MPa
• Yield Strength: Minimum 230 MPa
• Elongation: Minimum 15%
• Reduction of Area: 40–47%
• Hardness: 121–248 HB (Brinell Hardness)

These properties provide a good balance of strength, ductility, and toughness, enabling the steel to perform reliably under various conditions.

Compared to other carbon steels like AISI 1018, SAE AISI 1117 offers superior machinability due to its higher sulfur content. Additionally, its higher manganese content improves hardenability, making it more suitable for applications requiring deep and uniform case hardening.

Chemical Composition Breakdown

Main Chemical Elements and Their Roles

The chemical composition of SAE AISI 1117 carbon steel is meticulously balanced to provide excellent machinability and mechanical properties. Below is a detailed analysis of the primary elements and their respective roles:

Carbon (C)

• Typical Composition Range: 0.14% – 0.20%
• Carbon is the key element in steel that enhances hardness and strength, while maintaining good machinability at moderate levels. In SAE AISI 1117, the carbon content provides a balance between strength and ease of machining, making it suitable for high-volume production.

Manganese (Mn)

• Typical Composition Range: 1.00% – 1.30%
• Manganese enhances hardenability and tensile strength. It also improves the steel’s response to heat treatment and reduces brittleness. The relatively high manganese content in SAE AISI 1117 ensures better hardenability and mechanical robustness compared to other low-carbon steels.

Sulfur (S) and Phosphorus (P)

• Typical Composition Range for Sulfur: 0.08% – 0.13%
• Typical Composition Range for Phosphorus: Up to 0.04%
• Sulfur and phosphorus are added to improve machinability and maintain strength without causing brittleness. Sulfur forms manganese sulfide inclusions that act as lubricants during cutting operations, while phosphorus helps retain ductility.

Silicon (Si)

• Typical Composition Range: Approximately 0.10% – 0.40%
• Silicon helps remove oxygen from molten steel, improving strength and overall quality.

Aluminium (Al), Niobium (Nb), and Vanadium (V)

• Typical Composition Range for Aluminium: Up to 0.02%
• Typical Composition Range for Niobium: Up to 0.025%
• Typical Composition Range for Vanadium: Up to 0.05%
• Aluminium, niobium, and vanadium are present in small amounts to enhance steel quality. Aluminium acts as a deoxidizer, niobium refines grain size, and vanadium increases strength and wear resistance.

Iron (Fe)

• Typical Composition Range: Balance
• Iron is the principal base metal making up the bulk of the alloy. It provides the fundamental structure of the steel, to which other elements are added to achieve specific properties.

Notable Characteristics from the Composition

The specific chemical composition of SAE AISI 1117 carbon steel is carefully balanced to ensure excellent machinability, good mechanical performance, and overall high quality for various industrial applications. The high manganese content enhances hardenability and strength, while the controlled sulfur level improves machinability by promoting the formation of manganese sulfide inclusions. The moderate carbon content ensures a balance between hardness and ductility. Additionally, trace elements like niobium, vanadium, and aluminium contribute to grain refinement, toughness, and deoxidation, enhancing the overall quality of the steel.

Mechanical Properties and Performance

Tensile Strength and Yield Strength

SAE AISI 1117 carbon steel strikes a balance between tensile strength and yield strength, making it versatile for various engineering applications.

• Ultimate Tensile Strength (UTS): The ultimate tensile strength (UTS) of SAE AISI 1117 ranges from 430 to 540 MPa, indicating the maximum stress the material can withstand while being stretched or pulled before breaking. This variability is due to different heat treatment processes and conditions, such as cold drawing, which can enhance the strength.
• Yield Strength: The yield strength of SAE AISI 1117 ranges from 230 to 460 MPa, measuring the stress at which the material begins to deform plastically. The yield strength is highly dependent on the steel’s condition, whether it is annealed, cold-drawn, or heat-treated.

Hardness and Impact Resistance

Hardness and impact resistance are critical properties that determine the material’s ability to withstand wear and absorb energy during sudden impacts.

• Brinell Hardness (HB): The hardness of SAE AISI 1117 varies from 121 to 190 HB, depending on the treatment. Annealed conditions typically show lower hardness, while cold-drawn conditions yield higher values, indicating enhanced wear resistance.
• Impact Strength (Izod): The impact strength of annealed SAE AISI 1117 is approximately 93.6 J, reflecting the material’s toughness and ability to absorb energy during sudden impacts.

Elongation and Ductility

Elongation and ductility are measures of the material’s ability to undergo plastic deformation before breaking, which is essential for applications requiring flexibility and toughness.

• Elongation at Break: Elongation at break, ranging from 15% to 32.8%, shows the material’s capacity to stretch under tensile stress. Higher percentages indicate better ductility, allowing significant deformation before failure.
• Reduction of Area: This property, ranging from 40% to 58%, measures the reduction in cross-sectional area at the point of fracture. It reflects the material’s ability to undergo significant deformation before breaking, contributing to its overall toughness.

Other Mechanical Properties

In addition to the primary mechanical properties, SAE AISI 1117 possesses other characteristics that contribute to its performance in various applications.

• Elastic Modulus (Young’s Modulus): Approximately 190 to 210 GPa, this property indicates the material’s stiffness or resistance to elastic deformation under stress.
• Shear Modulus: Ranging from 73 to 80 GPa, it measures the material’s ability to resist shear deformation.
• Poisson’s Ratio: Typically between 0.27 and 0.30, this ratio describes the material’s tendency to expand in directions perpendicular to the direction of compression.

Performance Characteristics

SAE AISI 1117 carbon steel is known for its excellent machinability, making it ideal for high-volume machining operations. The resulfurized composition enhances this property by forming manganese sulfide inclusions, which act as internal lubricants during machining, reducing tool wear and improving surface finish.

• Machinability: The presence of sulfur forms manganese sulfide inclusions, which act as internal lubricants during machining. This reduces tool wear and improves the surface finish of the machined parts.
• Ductility and Toughness: The elongation and impact strength values indicate that SAE AISI 1117 can absorb significant energy and deform plastically before failure, which is beneficial in applications subjected to dynamic or shock loads.
• Hardening Capability: This steel grade is suitable for carburizing and case hardening treatments. The process develops a hard surface layer with a tough, ductile core, making it ideal for wear-resistant parts such as gears, shafts, and camshafts.
• Strength-to-Machinability Balance: With tensile strengths up to 540 MPa and yield strengths up to 460 MPa, SAE AISI 1117 offers a good compromise between strength and ease of machining, making it a preferred choice for components requiring moderate strength and excellent finish.

Manufacturing Processes Suitable for SAE AISI 1117

Hot Rolling and Cold Finishing

Hot Rolling

Hot rolling is essential for shaping SAE AISI 1117 carbon steel into forms like bars, rods, and plates. This process involves heating the steel above its recrystallization temperature, refining the grain structure, and enhancing its mechanical properties. The refined grain structure boosts the material’s toughness, making it suitable for subsequent forming and machining operations. Hot rolling also offers a cost-effective method for producing large quantities of steel with consistent properties.

Cold Finishing

Cold finishing processes, such as cold drawing and grinding, enhance the dimensional accuracy and surface finish of SAE AISI 1117. These processes are performed at room temperature, increasing the steel’s strength through strain hardening. Cold finishing is particularly beneficial for producing precision components, like shafts and gears, where tight tolerances and smooth surface finishes are essential. The excellent machinability of SAE AISI 1117 ensures that cold-finished parts maintain high quality and performance standards.

Forging

Forging is another suitable manufacturing process for SAE AISI 1117, especially when components require improved mechanical properties and directional grain flow. The steel’s composition supports hot forging at temperatures above critical points (approximately 900°C), which enhances its toughness and strength. Forging is ideal for structural and mechanical parts under dynamic loads, improving impact resistance, fatigue strength, and overall durability.

Machining

SAE AISI 1117 is widely recognized for its exceptional machinability, primarily due to its sulfur content. The sulfur creates manganese sulfide inclusions that act as lubricants, reducing tool wear and extending tool life. This steel is well-suited for various machining operations, including turning, milling, drilling, and threading. Its excellent machinability allows for the efficient production of precision parts with close tolerances, making it a preferred material in high-volume manufacturing environments. The reduced cycle times and tool costs further enhance its appeal for machining applications.

Heat Treatment Processes

Annealing

Annealing involves heating SAE AISI 1117 to about 855°C and then cooling it slowly. This process relieves internal stresses, increases ductility, and improves formability. Annealed SAE AISI 1117 is easier to machine and shape, making it suitable for applications requiring significant deformation.

Normalizing

Normalizing involves heating the steel above its critical temperature (approximately 900°C) and allowing it to cool in air. This process refines the grain structure, enhancing toughness and mechanical strength. Normalized SAE AISI 1117 is ideal for parts that require a balance of strength and toughness, as the refined grain structure improves the material’s overall performance.

Carburizing

Carburizing is a surface hardening process where SAE AISI 1117 is exposed to a carbon-rich environment at high temperatures. This process creates a hard, wear-resistant surface layer while maintaining a tough core. Carburized SAE AISI 1117 is commonly used for components like gears and shafts that require high surface hardness and durability.

Hardening and Tempering

Although hardening and tempering are less common for SAE AISI 1117 due to its sulfur content, they are still possible. Hardening involves austenitizing the steel at around 850°C, followed by quenching to form martensite. Tempering then reduces brittleness by reheating the steel to a lower temperature. However, the sulfur inclusions can compromise toughness in highly hardened states, making this process less favorable compared to others.

Forming and Joining

Forming

SAE AISI 1117 can be formed using conventional techniques such as bending, rolling, and stamping. Its moderate ductility in annealed or normalized conditions allows for easy shaping without cracking. These forming processes are essential for producing complex geometries and custom components in various engineering applications.

Joining

Welding and brazing are possible with SAE AISI 1117 but require careful handling due to its sulfur content, which can affect weld quality. Preheating and post-weld heat treatment are recommended to reduce the risk of cracking and ensure strong, reliable joints. Proper joining techniques enhance the material’s versatility and enable its use in a wide range of industrial applications.

Common Industrial Applications

SAE AISI 1117 carbon steel is prized for its exceptional machinability, making it an ideal material for precision components. The presence of sulfur enhances machinability by forming manganese sulfide inclusions, which act as internal lubricants during machining operations. This property significantly reduces tool wear and allows for the production of parts with tight tolerances and smooth surface finishes.

Gears

Gears made from SAE AISI 1117 benefit from the steel’s ability to undergo deep, uniform case hardening. This process creates a hard, wear-resistant surface while maintaining a tough core, ensuring the gears are durable and can handle high loads and repetitive motion.

Shafts

The balance between strength and machinability makes SAE AISI 1117 an excellent choice for shafts. These components often experience moderate mechanical stresses, particularly in automotive and machinery applications. The steel’s properties ensure that shafts are not only strong but also precisely machined to meet specific dimensional requirements.

Studs and Fasteners

Studs, bolts, and other fasteners demand high machinability and reliable mechanical performance. SAE AISI 1117 meets these requirements by offering excellent machinability and adequate strength, ensuring that the fasteners produced are dimensionally accurate and capable of withstanding mechanical stresses.

Steering Components

In automotive steering mechanisms, components made from SAE AISI 1117 need to be both precise and strong. The steel’s machinability allows for the production of parts with the necessary precision, while its mechanical properties ensure that the components can endure the stresses of steering operations.

Automotive and General Engineering

The combination of moderate carbon and higher manganese content in SAE AISI 1117 provides enhanced tensile strength and hardenability, making it suitable for various automotive and general engineering applications.

Automotive Parts

Automotive components such as valve parts, pump parts, and shafts benefit from the steel’s strength and machinability. These parts often need a good surface finish after machining and heat treatment, which SAE AISI 1117 can easily achieve.

General Engineering Components

In general engineering, the steel is used for parts that need both strength and precision. Its machinability ensures that these components can be produced efficiently and accurately, while its mechanical properties provide the necessary durability.

Carburized Parts

SAE AISI 1117 is particularly suited for carburization, a process that adds carbon to the surface layer to create a hard, wear-resistant exterior while keeping a tough core.

Gears and Pinions

Carburized gears and pinions made from SAE AISI 1117 exhibit excellent wear resistance at the surface, which is crucial for components that experience continuous contact and friction. The tough core ensures that these parts can handle the mechanical stresses of operation without failure.

Valve and Pump Components

Valve and pump components benefit from the surface hardening achieved through carburization. These parts need to withstand cyclic loads and wear, making the hard surface layer and tough core of SAE AISI 1117 ideal for such applications.

Structural and Fabrication Uses

While not as common as other structural steels, SAE AISI 1117 is useful in structures needing machining and moderate strength.

Structural Frameworks

The steel can be used in building frameworks and bridges where precision-fit parts are needed. Its machinability allows for the production of components that fit together accurately, ensuring the structural integrity of the framework.

Railway Station Components

In railway station construction and general fabrication applications, SAE AISI 1117 provides a balance of machinability and strength. This makes it suitable for producing components that require both precise machining and the ability to withstand mechanical loads.

Forms and Processing

SAE AISI 1117 is available in various forms, including bars, wire rods, plates, strips, sheets, and tubing. These forms are compatible with different manufacturing processes, such as hot rolling, cold finishing, forging, and various heat treatments, making the steel versatile across numerous industrial applications.

Benefits of Using SAE AISI 1117 in Machining and Forging

SAE AISI 1117 carbon steel offers exceptional machinability, which is one of its key benefits in machining. This property is primarily due to the presence of sulfur, which forms manganese sulfide inclusions within the steel. These inclusions act as internal lubricants during turning, milling, and drilling, making SAE AISI 1117 ideal for high-speed, precision machining applications where tight tolerances and excellent surface quality are crucial.

The machinability of SAE AISI 1117 contributes to increased efficiency in manufacturing processes. Reduced tool wear and cutting forces enable higher speeds and feed rates, shortening machining cycles. This efficiency not only reduces production time but also decreases operational costs by extending the life of cutting tools and reducing the frequency of tool changes. Additionally, the ability to achieve precise dimensions and smooth finishes enhances the quality of the final products, making this steel highly suitable for precision components.

SAE AISI 1117 offers a balanced combination of hardness and ductility, which is beneficial for both machining and forging processes. The carbon content (0.14–0.20%) ensures that the steel maintains sufficient hardness for machining while retaining enough ductility to prevent brittleness. This balance is critical in operations such as drilling and turning, where maintaining material integrity is essential. The steel’s ability to undergo case hardening further enhances its suitability for components requiring a hard, wear-resistant surface without compromising overall machinability.

The higher manganese content (1.00–1.30%) in SAE AISI 1117 improves its hardenability, making it an excellent candidate for case hardening processes like carburizing. This process develops a hard, wear-resistant surface layer while maintaining a tough, ductile core. The compatibility with case hardening makes SAE AISI 1117 ideal for manufacturing components such as gears, shafts, and other parts that require a combination of surface hardness and core toughness. The resulting parts can withstand high contact stresses and exhibit enhanced wear resistance, extending their service life.

The ductility of SAE AISI 1117 supports various forming operations, such as cold forming and hot forging. The steel’s composition allows it to be hot-rolled into various shapes like bars, plates, and tubing, providing flexibility in manufacturing processes. Cold forming operations benefit from the steel’s ability to produce intricate designs without cracking, making it suitable for complex automotive components. The predictability of its response to heat treatment and forging processes ensures uniformity and consistency, which is critical for high-volume production of components like valve bodies and pump parts.

The combination of superior machinability, efficient manufacturing processes, and the ability to produce high-quality parts with fewer defects contributes to the overall cost-effectiveness of SAE AISI 1117. The reduced tool wear and shorter machining cycles lower production costs, while the enhanced durability and performance of the final components reduce maintenance and replacement expenses. This cost-effectiveness makes SAE AISI 1117 a preferred choice for manufacturers looking to optimize production efficiency and product quality.

The predictable behavior of SAE AISI 1117 during machining and forging processes ensures that the material consistently meets the required specifications and performance standards. This reliability is crucial in industries such as automotive and general engineering, where the consistency of materials directly impacts the safety and performance of the final products. The steel’s ability to maintain uniform properties across large production batches enhances its appeal for high-volume manufacturing applications.

Comparison with Other Carbon Steels (e.g., AISI 1018)

Comparative Analysis of SAE AISI 1117 and AISI 1018

Chemical Composition Differences

The key differences in chemical composition between SAE AISI 1117 and AISI 1018 are primarily in their manganese and sulfur contents.

SAE AISI 1117:

• Carbon Content: 0.14-0.20%
• Manganese Content: 1.00-1.30%
• Sulfur Content: 0.08-0.13%

AISI 1018:

• Carbon Content: 0.15-0.20%
• Manganese Content: 0.60-0.90%
• Sulfur Content: Negligible

SAE AISI 1117’s higher manganese content enhances its hardenability and strength, while the added sulfur significantly improves its machinability compared to AISI 1018, which has negligible sulfur content.

Mechanical Properties Comparison

SAE AISI 1117:

• Tensile Strength: 490-540 MPa
• Yield Strength: 260-460 MPa
• Elongation: 15-32.8%
• Brinell Hardness: 121-190 HB

AISI 1018:

• Tensile Strength: 440-490 MPa
• Yield Strength: 370 MPa
• Elongation: 15-20%
• Brinell Hardness: 126 HB

SAE AISI 1117 typically provides higher tensile and yield strengths than AISI 1018, primarily due to its higher manganese content. SAE AISI 1117’s wider range of elongation shows it can deform significantly before breaking, which can be advantageous in certain applications.

Machinability and Hardenability

Machinability:

• SAE AISI 1117: Excellent machinability due to the sulfur content, which forms manganese sulfide inclusions acting as internal lubricants during cutting operations.
• AISI 1018: Good machinability but less than SAE AISI 1117 due to the absence of sulfur.

Hardenability:

• SAE AISI 1117: Higher hardenability from increased manganese, ideal for deep case hardening applications.
• AISI 1018: Lower hardenability, making it less suitable for applications where deep hardening is required.

Industrial Applications

SAE AISI 1117:

• SAE AISI 1117 is ideal for automotive components like gears and shafts, as well as general engineering parts that benefit from excellent surface finish and reduced machining costs.

AISI 1018:

• Structural Applications: General purpose engineering applications where lower strength and machinability are acceptable.
• Cold-Formed Parts: Components that require good formability and moderate strength.

SAE AISI 1117’s enhanced machinability and higher strength make it a more cost-effective choice for precision machining applications compared to AISI 1018. This comparison highlights the suitability of SAE AISI 1117 for applications requiring high machinability and moderate strength, providing clear benefits in terms of manufacturing efficiency and product performance.

Standards Compliance

Relevant Industry Standards

ASTM Standards

ASTM A108: ASTM A108 compliance guarantees consistent chemical and mechanical properties in steel bars, ideal for precision engineering. This standard ensures uniformity in production, providing reliable material quality for high-precision components.

ASTM A576: This specification covers hot-rolled carbon steel bars used for mechanical applications. Meeting ASTM A576 ensures that SAE AISI 1117 steel bars possess the necessary mechanical properties for structural and mechanical parts subjected to stress and machining. This standard is crucial for ensuring the material’s performance in demanding applications.

SAE and AISI Designations

SAE (Society of Automotive Engineers) and AISI (American Iron and Steel Institute) jointly designate this carbon steel as 1117, standardizing its chemical composition and properties across the industry. This designation ensures that SAE AISI 1117 conforms to expected performance parameters, facilitating its use in various industrial applications. The UNS (Unified Numbering System) number G11170 further identifies this steel grade globally, ensuring traceability and consistency.

Chemical Composition Compliance

The chemical composition of SAE AISI 1117 is tightly controlled to balance machinability, strength, and ductility. Typical ranges for key elements include Carbon (C): 0.14 – 0.20%, Manganese (Mn): 1.00 – 1.30%, Phosphorus (P): ≤ 0.040%, and Sulfur (S): 0.08 – 0.13%. This formulation meets industry standards for performance and improves machinability. The elevated manganese content improves hardenability, and the sulfur additions form manganese sulfide inclusions that facilitate machining.

Mechanical Properties Compliance

Typical mechanical properties for SAE AISI 1117 steel, as specified by industry standards, include:

• Tensile Strength (psi): 82,000 – 92,000
• Yield Strength (psi): 72,000 – 82,000
• Elongation (%): 15 – 20
• Reduction of Area (%): 50 – 60
• Brinell Hardness (BHN): 160 – 190

Meeting these specifications ensures the material withstands mechanical stresses and performs well in various applications.

Heat Treatment and Compliance

SAE AISI 1117 can undergo various heat treatments to enhance its mechanical properties further. The steel’s composition allows for effective quenching and tempering, while maintaining machinability. Heat treatments must meet specified mechanical properties to ensure the material’s effectiveness in intended applications.

Compliance with these standards ensures that SAE AISI 1117 carbon steel delivers a reliable balance of machinability, strength, and ductility, making it a preferred choice in the automotive, machinery, and precision engineering sectors. Adherence to these standards guarantees that products made from 1117 steel meet industry expectations for quality and performance.

Frequently Asked Questions

Below are answers to some frequently asked questions:

What is the chemical composition of SAE AISI 1117 carbon steel?

SAE AISI 1117 carbon steel is characterized by its specific chemical composition tailored for high machinability and moderate strength. The carbon content ranges from 0.14% to 0.20%, which provides a balance between hardness and machinability. Manganese is present in higher amounts (1.00% – 1.30%) to enhance hardenability and tensile strength, while sulfur (0.08% – 0.13%) significantly improves machinability by forming manganese sulfide inclusions. Phosphorus is kept below 0.04% to maintain toughness and prevent brittleness. Silicon, ranging from approximately 0.10% to 0.40%, acts as a deoxidizer and contributes to strength. Trace elements like aluminium (up to 0.02%), niobium (up to 0.025%), and vanadium (up to 0.05%) may be included to improve steel cleanliness, grain refinement, and wear resistance. The balance of the composition is iron. This chemical makeup ensures SAE AISI 1117 is well-suited for applications requiring excellent machinability and reasonable mechanical performance.

What are the mechanical properties of SAE AISI 1117 carbon steel?

SAE AISI 1117 carbon steel exhibits a range of mechanical properties that make it suitable for various engineering and manufacturing applications. It has an ultimate tensile strength (UTS) ranging from 430 to 540 MPa, with a yield strength between 230 and 460 MPa. This steel type is known for its good ductility, with elongation at break typically between 15% and 32.8%, and a reduction of area from 40% to 58%. Its hardness varies with treatment; in annealed conditions, it ranges from 121 to 248 HB, and in cold-drawn states, it typically falls between 160 and 190 HB. SAE AISI 1117 also features a Young’s modulus of 190 to 210 GPa and a shear modulus of 73 to 80 GPa, with a Poisson’s ratio of 0.27 to 0.30. Additionally, it has an Izod impact strength of approximately 93.6 J. These properties, combined with its enhanced machinability due to higher sulfur content, make SAE AISI 1117 a versatile material for automotive parts, machined components, and general engineering uses.

What are typical uses of AISI 1117 carbon steel?

AISI 1117 carbon steel is commonly used in various industrial applications due to its excellent machinability and reliable mechanical properties. Typical uses include:

1. Automotive Components: It is frequently utilized in manufacturing shafts, gears, and other precision-machined parts that require both strength and surface hardening for wear resistance.
2. General Engineering Applications: The steel’s adaptability to processes like hot-rolling, cold-finishing, and forging makes it suitable for producing parts such as shafts, pins, studs, and fasteners, which are subject to moderate stresses.
3. Valve and Pump Parts: Its ability to achieve deep and uniform case hardening makes it ideal for components like valve stems and pump shafts that need a tough core and a hard, wear-resistant surface.
4. Parts Subject to Shock and Vibrations: Due to its mechanical properties, AISI 1117 is suitable for machine parts experiencing shock or vibrating stresses, such as certain couplings and mechanical linkages.
5. Machined or Carburized Components: The steel’s higher sulfur content enhances machinability, facilitating the manufacture of parts requiring extensive machining or carburizing, such as precision gears and carburized shafts.

These applications benefit from AISI 1117’s balanced mechanical properties, enhanced machinability, and versatility in various forms, making it a preferred material in industries requiring durable and precisely machined components.

How does SAE AISI 1117 compare to other carbon steels like AISI 1018?

SAE AISI 1117 carbon steel is distinguished from AISI 1018 by its enhanced machinability and hardenability, primarily due to its higher sulfur (0.080 – 0.130%) and manganese (1.000 – 1.300%) content. This composition makes AISI 1117 more suitable for applications requiring precise and efficient machining, such as gears, shafts, and various automotive components. AISI 1018, with its lower carbon content and lower sulfur levels, offers good weldability and is commonly used in general engineering applications where these properties are advantageous.

In terms of mechanical properties, AISI 1117 typically exhibits higher tensile strength (429.5 MPa to 540 MPa) and yield strength (230 MPa to 460 MPa) compared to AISI 1018 (tensile strength of 380 MPa to 520 MPa and yield strength of 220 MPa to 420 MPa). The elongation and hardness of AISI 1117 also provide it with a good balance of ductility and strength, enhancing its performance in demanding machining and forging processes.

What are the benefits of using SAE AISI 1117 in machining?

Using SAE AISI 1117 carbon steel in machining offers several notable benefits. This steel is resulfurized, which enhances its machinability significantly. The addition of sulfur makes cutting processes more efficient, reducing tool wear and lowering production costs, thus increasing overall productivity. AISI 1117 also provides a balanced combination of strength and ductility, making it suitable for applications requiring both mechanical integrity and formability. Additionally, the higher manganese content ensures good hardenability, which is beneficial for case hardening processes. This steel’s versatility in heat treatment allows for various processes, including carburization, enhancing wear resistance for industrial applications like automotive parts, valves, and pumps. Compared to other carbon steels like AISI 1018, AISI 1117 offers superior machinability and hardenability, making it a reliable choice for precision engineering and manufacturing.

What standards does SAE AISI 1117 comply with?

SAE AISI 1117 carbon steel complies with several important industry standards, ensuring its quality and performance for various applications. Specifically, cold-drawn 1117 steel bars typically meet the ASTM A108 and ASTM A576 specifications. These standards govern the material’s mechanical properties and manufacturing processes, ensuring consistency and reliability in its use. Compliance with these standards makes SAE AISI 1117 suitable for applications requiring high machinability and precision, such as gears, studs, and shafts in the automotive and general engineering sectors. Always verify specific compliance requirements based on the intended application and manufacturing needs.