Wednesday, December 4, 2019

How Brass Is Made


















An alloy of copper and zinc, brass is typically a muted gold color, though this may be affected by the amount of zinc in the alloy. It is often confused with bronze, which is an alloy of copper and tin. Brass is reasonably hard, strong, and malleable. It is an excellent heat conductor and imparts excellent acoustic properties to musical instruments. Brass is somewhat corrosion resistant, and it can be made more so through the addition of iron, silicon, aluminum, and/or manganese to the alloy.

Besides musical instruments, brass is often used for piping and tubing, architectural trim, boat hardware, screws, and such low-friction applications as zippers, gears, doorknobs and locks, valves, and ammunition. It is not prone to sparking, making it an excellent choice for tools and fittings that will be used around explosive gases.

The Manufacturing Process

Brass stock is available in a variety of different forms, depending on the final product that will be made. For example, brass pipes and tubes are made by extruding rectangular billets of hot brass through a die, while brass screws are cut from a piece of brass rod. Therefore, the exact manufacturing process will vary depending on the form of brass stock that is being created. Still, the majority of the process is the same until the final steps.

Steps to Manufacturing Brass Sheet

Brass sheet is a flat, rectangular piece of brass that can be cut into strips. It is a very common raw material, and its manufacturing process is an excellent representation of how all brass is made:


Step 1 – Melting: The first step is to melt the copper alloy at a temperature of approximately 1050 C. Additional zinc may be added to account for vaporization during melting. If other materials will be included, such as iron or manganese, they are added in this step.


Step 2 – Molding: The molten metal is then poured into molds measuring 8 inches x 18 inches x 10 feet and cooled into cakes.


Step 3 – Storage: The cooled cakes are removed from the molds and stored near the rolling area until needed.


Step 4 - Reheating: The cake is reheated in a furnace to the appropriate temperature, which will vary based on the desired final properties of the brass stock.


Step 5 - Hot rolling: The heated cake is fed through opposing steel rollers to increase its width and reduce its thickness to 0.5 inch or less.


Step 6 – Scalping: A milling machine known as a scalper removes a thin slice from each outer face of the brass to remove oxides that developed from exposure to the air while the brass was hot.


Step 7 – Annealing: In a process known as annealing, the brass is reheated in a furnace filled with nitrogen or another neutral gas to restore ductility, or the ability to stretch. The exact temperature varies, but it is much lower than the original reheating temperature.


Step 8 – Cold rolling: The brass is fed through another set of rollers, reducing its thickness to approximately 0.1 inch. This cold rolling process increases hardness and strength by deforming the grain, or internal structure, of the brass.

Steps 7 and 8 may be repeated one or more times to achieve the desired final properties.

Optional Steps


Step 9 – Stripping: If desired, the brass sheet may be passed through a cutting machine to create strips. Each strip is typically cleaned in an acid bath and then rinsed.


Step 10 – Finish rolling: The brass sheet or strip may be cold rolled once more to tighten tolerances and improve the smoothness of the surface.

Ready to Start?

Atlas Bronze is a leading U.S. distributor of bronze, copper, brass, iron, and more. Contact us today at 1-800-478-0887 to place an order or learn about our custom products.

No comments:

Post a Comment