Sprockets
AMAG Materials Powering High-Performance Drive Systems
Whether in bicycles or motorcycles, sprockets are essential components of modern drive systems. They transmit power from the crank or engine via the chain to the wheel, enabling efficient, controlled propulsion. Throughout their service life, sprockets are subjected to cyclic tensile forces on the tooth flanks, often under high loads and in harsh environments, including dirt, moisture, and dynamic load changes. This makes the choice of material critical for durability, reliability, and overall performance. At the same time, high-end surface quality and, increasingly in the premium segment, sustainability are moving into the spotlight.
Alloy selection between strength and formability
Emerging from the balance between technical and aesthetic requirements, AMAG has established two key alloys for sprocket applications: 7075 for high-strength, precision-machined components, and 2014 for forming-intensive, geometrically complex applications. While 7075 stands out for its exceptional tensile strength and dimensional stability, 2014 offers excellent cold formability and is particularly suitable for stamped parts.
For both alloys, the casting and rolling processes are based on aerospace standards. This means, among other things, that heat treatments are carried out in Nadcap-certified facilities, ensuring consistently high product quality and repeatable properties across strip length, width, and from batch to batch. For customers, this translates into advantages such as improved creep resistance, reduced rejection rates, and stable production performance across different lots.
7075 – The High-End Alloy for Maximum Demands
The 7075 alloy variant used by AMAG is more highly alloyed than the classic aerospace grade, enabling higher mechanical properties in the T6 temper. It achieves tensile strengths of up to 600 MPa, combining this strength with sufficient elongation - a prerequisite for the precise and durable manufacturing of highly loaded gear profiles. Dimensional stability under load is crucial to maintain form and fit throughout the component’s entire service life.The quality of AMAG’s 7075 material begins already in the casting process: a specially modified filter bag system ensures a particularly homogeneous microstructure and reduces inclusions, resulting in a noticeably more uniform surface appearance.Subsequent hot and cold rolling is performed with extremely tight thickness tolerances. This precision in sheet thickness is critical for downstream production steps and the final quality of the sprockets. The sheets are continuously monitored and precisely measured to ensure compliance with these stringent standards. For the soft-annealed condition, the grain size has been adjusted to optimize high-temperature creep behavior. This adaptation minimizes component distortion during the customer’s subsequent solution heat treatment, simplifying post-processing and ensuring greater production stability, even for complex geometries. Thanks to its high dimensional accuracy, excellent surface quality, and improved machinability, the 7075 alloy is particularly well-suited for demanding manufacturing processes such as CNC milling and laser cutting.
2014 – The Complement for Forming-Intensive Processes
In addition to 7075, AMAG offers the alloy 2014, a material characterized by good formability and strength at elevated temperatures, making it particularly suitable for stamped and forming-intensive components. Furthermore, this alloy provides excellent strength, good elongation properties, and outstanding formability. This makes it particularly suitable for stamped sprockets or geometrically complex components.To maximize the mechanical properties in the T6 temper, the solution heat treatment in the continuous annealing furnace has been specially adapted. In addition, AMAG takes into account the customer’s specific ageing conditions, ensuring optimal coordination between the material and the subsequent heat treatment. This adjustment enables the alloy to be ideally prepared for forming processes without compromising the strength required in the final application. In terms of surface quality, 2014 also meets the highest standards: a specially developed surface inspection system integrated into the continuous annealing furnace ensures particularly thorough sheet monitoring, guaranteeing a uniform and high-quality surface finish.Whether in plate, sheet, or coil form, AMAG supplies material formats that are precisely tailored to customers’ processing and logistics requirements. Consistently high quality across all formats ensures reproducible results in large-scale production, small batches, or customized components.
Materials expertise for the drive systems of tomorrow
Increasing torques, the trend toward lightweight construction, functional surfaces, and stricter CO₂ targets are shaping material selection today and in the future. AMAG supports this transformation not only with high-performance alloys, but also through the continuous optimization of existing materials, the development of new temper variants, and close collaboration with customers already in the design phase. The result is advanced material solutions that enable precise, durable, and sustainable components - ready to meet the demands of future drive systems.
Customer benefits
- Stable properties for highly loaded applications and complex geometries
- Consistent surface quality ensuring reproducible anodizing results
- Tight tolerances in thickness and flatness for high process reliability
- Transparency regarding the CO₂ footprint
- Technical support in material selection and application
- Tighter thickness tolerances than those required in the aerospace sector
AMAG AL4® ever – guaranteed carbon footprint, full performance
With AMAG AL4® ever, AMAG offers a product line with a guaranteed CO₂ footprint without compromising on material performance.
For example, AMAG 7075 AL4® ever 6 provides the same material properties as the standard grade, but with a guaranteed CO₂ footprint of less than 6 kg per kilogram of aluminium (cradle to gate).
The system is based on predefined CO₂ levels, which are verified by a plant certificate specific to each product and quantity. This certification ensures transparency of Scope 3 emissions and supports customers in their sustainability communication making it an ideal solution for companies with ambitious environmental goals and the highest quality standards.
