When choosing materials for drop forged parts, aluminum and brass are commonly considered. Both forged aluminum and forged brass share the same process of drop forging, resulting in forged parts with high strength, precise tolerances, and excellent surface finish. However, there are notable differences between these materials that are important to understand before making a decision.
Forged aluminum is renowned for its lightweight properties while maintaining strength. Typical aluminum alloys used for forging include 6061, 6063, 6082, and 7075. Additionally, aluminum alloys can also be used in casting, such as A356 and A380. It's crucial not to confuse cast aluminum with forged aluminum, as they undergo different manufacturing processes and use different aluminum grades.
In addition to being lightweight, forged aluminum is relatively soft compared to forged steel or brass. If further machining is required, aluminum forgings may need to undergo heat treatment, typically in T6 condition, to improve hardness effectively.
Brass, an alloy of copper and zinc, is named for its characteristic yellow color. It offers good mechanical properties and wear resistance, making it suitable for forged parts like valves, pipe fittings, and air conditioning components. Brass forging involves shaping heated brass bars, leveraging their excellent hot deformability.
The brass forging process begins with cutting brass bar stock into pre-cut cylindrical blanks or billets, which are then heated to a pliable state. Each billet is pressed between dies at high pressure to form the basic shape of the part. After forging, any excess material is trimmed away, and the part may undergo shot blasting or further machining for finishing.
Key Differences:
Color: Forged aluminum maintains a silver color, while forged brass has a distinct golden yellow hue, making them easily distinguishable by color.
Heating Temperature: While both materials require lower heating temperatures than forged steel, the heating temperature for aluminum forging is approximately 300°C - 480°C, whereas for brass forging, it's around 815°C.
Cost: Forged brass tends to be more expensive due to higher material costs, while forged aluminum is more budget-friendly.
Applications: Forged aluminum is preferred for lightweight applications like automotive and motorcycle parts, whereas forged brass finds wider use in fittings and components for valves, piping, air conditioning, and firefighting systems.
