Bronze 936 (C93600): Composition, Properties, and Uses
Imagine a material that combines remarkable strength, excellent wear resistance, and superior machinability. Bronze 936, also known as C93600, is…
In the world of metallurgy, few alloys offer the versatility and dependability of High-Leaded Tin Bronze UNS C93200. Known for its excellent machinability and superior corrosion resistance, this alloy stands as a cornerstone in industrial applications ranging from automotive components to complex machinery. But what exactly makes C93200 so unique? Delving into its chemical composition reveals a precise blend of copper, lead, tin, and other elements, each playing a critical role in enhancing its performance attributes. Beyond its composition, understanding the mechanical properties of C93200 unveils its suitability for demanding environments where durability and reliability are paramount. Engineers and manufacturers alike are drawn to its anti-friction qualities, making it an ideal choice for bearings and bushings. As we explore the standards and specifications, including ASTM B505/B505M and SAE 660, this article will illuminate why C93200 remains a preferred material in various sectors. Whether you’re an industry professional seeking technical insights or a curious reader eager to learn about one of the most adaptable bronze alloys, this deep dive into High-Leaded Tin Bronze UNS C93200 will equip you with the knowledge to appreciate its widespread use and enduring legacy.
C93200 High-Leaded Tin Bronze, commonly known as SAE 660, is a standout alloy in the metal materials industry due to its exceptional performance and cost-effectiveness. This versatile alloy primarily consists of copper, tin, and lead, each contributing to its distinct properties and broad range of uses.
The alloy is significant for its excellent wear resistance, self-lubrication, and ease of machining, making it essential in demanding industrial environments. C93200 is extensively used in producing bearings, bushings, and components that require high-speed and high-load performance. Its ability to reduce friction and wear, thanks to lead’s lubricating qualities, enhances the durability and efficiency of mechanical systems.
C93200 is popular in automotive, machinery, and heavy equipment manufacturing. Its uses range from bearings and bushings to pump and valve components, demonstrating its versatility and reliability. The alloy’s corrosion resistance in non-corrosive environments further extends its applicability, making it a preferred material for many engineers and manufacturers.
Understanding the key characteristics and applications of C93200 High-Leaded Tin Bronze helps professionals make informed decisions, ensuring optimal performance and longevity of their components.
C93200 High-Leaded Tin Bronze, also known as SAE 660, contains a mix of elements that give it unique properties. This copper-based alloy is renowned for its excellent machinability, corrosion resistance, and lubricating characteristics.
Copper (Cu): Making up 81.0% to 85.0% of the alloy, copper forms the alloy’s base, enhancing conductivity, strength, and malleability.
Lead (Pb): Ranging from 6.0% to 8.0%, lead improves machinability and provides self-lubricating properties to reduce friction and wear, ideal for applications like bearings and bushings.
Tin (Sn): Comprising 6.3% to 7.5%, tin adds strength, hardness, and corrosion resistance, enabling the alloy to excel in diverse environments.
Zinc (Zn): Present in amounts of 2.0% to 4.0%, zinc strengthens the alloy and enhances corrosion resistance alongside tin.
Iron (Fe): Limited to a maximum of 0.20%, iron refines the alloy’s microstructure without altering its main properties.
Phosphorus (P): Found in minimal quantities, up to 0.15% for continuous castings and 1.50% overall, phosphorus deoxidizes the alloy and refines its grain structure.
Nickel (Ni): With a maximum of 1.00%, nickel (and occasionally cobalt) improves mechanical strength and wear resistance.
Antimony (Sb): Up to 0.35%, antimony increases hardness and wear resistance, extending the alloy’s durability.
Sulfur (S): Present in very small amounts, not exceeding 0.08%, sulfur is controlled to prevent adverse effects on the alloy’s performance.
Aluminum (Al) and Silicon (Si): Present in trace amounts, with minimal impact on the alloy’s properties.
C93200 High-Leaded Tin Bronze meets industry standards like ASTM B505/B505M and SAE 660, ensuring consistent performance and quality for industrial applications. With its excellent machinability, strength, and corrosion resistance, C93200 is ideal for bearings, bushings, and other high-performance applications.
C93200 High-Leaded Tin Bronze is highly valued for its outstanding machinability and self-lubricating properties, making it ideal for precision components. Its high lead content allows for smoother machining and longer tool life, which are crucial for manufacturing efficiency and cost-effectiveness. However, welding this alloy is not recommended due to risks of defects and uneven lead distribution, which can compromise the integrity of the weld.
With a density of 0.322 lb/cu in., C93200 provides substantial stability for structural applications. Its moderate thermal conductivity ensures effective heat management, which is vital in applications where temperature control is critical, such as in heat exchangers and industrial machinery.
The modulus of elasticity in tension for C93200 is about 14,500 ksi. This property allows the alloy to withstand deformation under stress, making it suitable for components that experience heavy loads.
The tensile strength of C93200 varies by casting method. Continuous castings achieve a minimum of 35 ksi, while centrifugal and sand castings have a minimum tensile strength of 30 ksi. These strengths ensure the alloy can support significant loads without failure.
C93200 demonstrates good resistance to corrosion, particularly in non-corrosive and mildly corrosive environments. Its resistance to seawater corrosion makes it particularly suitable for marine applications, where durability and longevity are essential.
The high lead content in C93200 provides exceptional anti-friction qualities. These self-lubricating features reduce wear, meaning components like bearings last longer with minimal maintenance, which is beneficial in reducing downtime and maintenance costs.
With a Brinell hardness of 65 to 70, this alloy can withstand heavy use, making it reliable for high-load applications. Its compressive strength of about 46 ksi ensures durability, even in demanding conditions.
The alloy’s ability to endure repeated stress over time ensures reliability in dynamic applications. With a fatigue strength of approximately 16 ksi at 100 x 10^6 cycles, C93200 is a dependable choice for components subjected to continuous or cyclic loads.
C93200 High-Leaded Tin Bronze is a highly valued material in various industries due to its exceptional properties. This alloy is particularly known for its versatility and effectiveness in multiple applications, ensuring reliable performance and longevity.
C93200 is ideal for bearings and bushings, thanks to its excellent self-lubricating properties. The high lead content acts as a natural lubricant, reducing friction and wear. This makes the alloy perfect for medium-load and medium-speed applications, such as industrial machinery, automotive systems, and heavy equipment.
The alloy’s corrosion resistance and dimensional stability make it a preferred choice for pump and valve components. It is commonly used in pump impellers, valve guides, and hydraulic press components. Its ability to withstand pressure and resist wear ensures reliable performance in fluid-handling systems.
In the automotive and industrial sectors, C93200 is used for:
These components benefit from the alloy’s machinability and wear resistance, allowing for precise and durable parts that perform well under high-load conditions.
C93200’s resistance to seawater corrosion makes it suitable for marine environments. It is often used in marine bearings and bushings, which require durability in saltwater conditions. For example, it can be found in ship propeller systems, where long-term reliability is crucial.
The alloy is also ideal for wear plates and thrust washers, crucial in systems with repetitive motion or high contact stress, like presses and conveyors. Its ability to reduce friction and handle heavy loads ensures consistent performance and longevity.
C93200 is frequently employed in rolling mill and machine tool bearings due to its excellent load-bearing capacity and wear resistance. These characteristics support the demanding conditions of industrial processes, ensuring smooth and efficient operation.
This alloy’s versatility makes it suitable for a wide range of general-purpose bushings and insert bearings. Found in various industrial systems, these components benefit from C93200’s ease of machining and wear resistance, offering reliable performance across diverse applications.
In hydraulic presses, C93200 is used for liners and stuffing boxes, which require strength, stability, and wear resistance. Compared to alternative materials, C93200 offers superior performance under high pressures and repetitive stresses, making it a dependable choice for heavy-duty applications.
C93200 High-Leaded Tin Bronze conforms to several industry standards that guarantee its quality and suitability for diverse applications. These standards define the alloy’s chemical composition, mechanical properties, and casting methods, ensuring consistent quality and performance. This makes the alloy a reliable choice for manufacturers and engineers.
Adhering to these standards guarantees that C93200 performs consistently in various applications, giving manufacturers confidence in its durability and machinability. Compliance provides assurance in the material’s reliability, making it a trusted choice for critical components such as bearings, bushings, and valve components.
Certified manufacturers often provide material test reports (MTRs) with each batch of C93200. These reports verify compliance with key requirements, providing traceability and assurance to users.
C93200 High-Leaded Tin Bronze is known for its excellent soldering properties, making it ideal for applications that require durable, reliable joints. While not as optimal as soldering, brazing is still a good option for creating joints where higher temperature resistance is needed.
Welding is generally not advised for C93200 due to the risk of defects like porosity and lead segregation, which can compromise weld quality. For this reason, alternative joining methods such as mechanical fastening or adhesive bonding are often preferred.
C93200 offers high casting yield with minimal waste and low drossing, ensuring purity and reducing the need for extensive cleaning. This makes it an economically advantageous choice for large-scale production.
C93200’s medium fluidity allows it to fill molds effectively for detailed designs, but careful control of casting conditions is necessary to manage its medium gassing tendency. Proper venting and degassing techniques are essential to ensure high-quality castings.
Patternmakers should account for a 7/32 inch per foot shrinkage rate, enabling precise mold design and accurate part dimensions. This predictable shrinkage rate allows for meticulous planning and execution in mold creation.
Larger sections of C93200 may vary in mechanical properties, so design adjustments and controlled casting techniques are crucial for uniform quality. This consideration ensures that all sections of a component meet the required performance standards, regardless of size.
C93200 High-Leaded Tin Bronze is known for its unique blend of copper, tin, lead, and zinc, with copper being the primary component. This mix enhances machinability and provides self-lubricating qualities. While tin bronzes, like C90300 and C90500, use tin for strength and corrosion resistance, aluminum bronzes such as C95400 include aluminum for high strength and excellent heat resistance.
C93200 is designed for high machinability and wear resistance due to its lead content, which also offers excellent anti-friction properties. Compared to lead-free tin bronzes, C93200 is easier to machine but might not handle high loads as well. Aluminum bronzes provide superior strength and can be heat-treated, making them ideal for heavy-duty and high-temperature uses.
C93200 resists corrosion well in less harsh environments, perfect for many industrial uses. Tin bronzes are great for marine applications due to their resistance to seawater, while aluminum bronzes excel with their protective oxide layer, offering better durability in tough conditions.
C93200 is perfect for bearings and bushings where its self-lubricating and machinability traits shine. Tin bronzes suit high-strength and flexible needs, while aluminum bronzes are chosen for their durability in demanding, high-load settings.
C93200 offers cost benefits due to its ease of machining, reducing production expenses. Although aluminum bronzes are more expensive, their durability and low maintenance needs provide long-term savings in challenging applications.
In summary, C93200 is ideal for applications needing high machinability and self-lubrication. While it excels in these areas, tin and aluminum bronzes offer unique strengths in terms of durability and environmental resistance, emphasizing the need to choose the right alloy for the job.
Below are answers to some frequently asked questions:
The chemical composition of C93200 High-Leaded Tin Bronze, also known as SAE 660 Bronze, is as follows: Copper (Cu) 81.0 – 85.0%, Tin (Sn) 6.3 – 7.5%, Lead (Pb) 6.0 – 8.0%, Zinc (Zn) 2.0 – 4.0%, Iron (Fe) 0.20% max, Nickel (Ni) including Cobalt 1.00% max, Antimony (Sb) 0.35% max, Phosphorus (P) 1.50% max, Sulfur (S) 0.08% max, Aluminum (Al) 0.005% max, and Silicon (Si) 0.005% max. The combined total of these elements accounts for 99.0% of the alloy.
C93200 High-Leaded Tin Bronze exhibits excellent physical and mechanical properties that make it ideal for demanding applications. Physically, it has a density of 0.322 lb/in³ (8.91 g/cm³) and a thermal conductivity of 33.6 Btu·ft/(hr·ft²·°F) at 68°F (58.2 W/m·K at 20°C). Its coefficient of thermal expansion is 10 × 10⁻⁶ per °F (68-212°F) or 18.0 × 10⁻⁶ per °C (20-100°C), with a modulus of elasticity in tension of 14,500 ksi (100,000 MPa). Mechanically, it has a tensile strength of at least 35 ksi (241 MPa), yield strength of 20 ksi (138 MPa), and elongation of 10%. The typical Brinell hardness is 65, and it offers a machinability rating of 70 (compared to free-cutting brass at 100). These properties, combined with its excellent anti-friction and wear resistance, make it suitable for bearings, bushings, and other components exposed to medium loads and speeds, especially in conditions with intermittent lubrication or contamination.
C93200 High-Leaded Tin Bronze is widely used in various applications due to its excellent properties. It is extensively utilized for bearings and bushings because of its good anti-friction properties, high hardness, and wear resistance. The alloy is also suitable for light-duty gears and sprockets, especially where medium loads and speeds are involved with adequate lubrication. In industrial applications, it serves well for pump impellers, pump parts, and valve components due to its good corrosion resistance in seawater and brine conditions. Additionally, it is employed in machine tools, hydraulic press components, automotive fittings, and marine products. C93200 is also used for wear strips, plates, and various fixtures and fittings across different industries, thanks to its excellent machinability and strength.
C93200 High-Leaded Tin Bronze, known for its excellent machinability and good corrosion resistance, stands out among bronze alloys. Its machinability rating of 70 is relatively high due to the presence of lead, which acts as a lubricant, facilitating smoother and more efficient machining with reduced tool wear. This makes C93200 easier to machine than non-leaded bronze alloys, such as phosphor bronze and aluminum bronze, which do not offer the same lubrication benefits.
In terms of corrosion resistance, C93200 performs well, particularly in seawater and brine environments, thanks to its high copper content and resistance to dezincification corrosion. While it may not match the exceptional corrosion resistance of copper-nickel bronzes used in marine applications, it is well-suited for various industrial uses, including bearings and bushings, where medium loads and adequate lubrication are present. Overall, C93200 is a versatile choice for applications requiring a balance of machinability and corrosion resistance.
C93200 High-Leaded Tin Bronze is governed by several standards and specifications that ensure its quality and suitability for various applications. The relevant standards for this alloy include ASTM B271, ASTM B505, and ASTM B584. It also meets SAE specifications such as SAE 660, SAE J461, and SAE J462. Additionally, C93200 conforms to federal and military specifications like QQ-C-390, E7, and MIL-B-11553, Comp 12. These standards cover aspects such as chemical composition, mechanical properties, and casting requirements, ensuring the alloy’s performance in industrial applications.
