Corrosion of Metals—How Naval Brass Survives the Process

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Decomposition is a natural process that affects both living and non-living things. You may think that only organic objects decay and return to dust after expiring, but in truth, even the inorganic ones are fated to deteriorate eventually. They only follow a rather different decomposition process, which takes longer. Metals, for instance, decompose through corrosion. Some metals rust when exposed to oxygen, while others develop a patina on their surface.

Corrosion comes in a range of forms, each of which is classified by the cause of chemical deterioration. Understanding how each type of corrosion works can help you perform the necessary preventive measure, which would allow you to enhance the durability of your project output. This also helps you carry out the right procedure in case there’s a need to speed up corrosion. Below are the most common types of corrosion that could occur either naturally or purposefully.

Uniform Attack

This type of corrosion targets all exposed surfaces and occurs at a uniform rate, as the name suggests. It usually takes place when the entire object is exposed to a corrosive chemical compound, for instance, when submerged in saltwater or acid. The most prominent example is rust developing on the surface of structural steel bars. The oxygen from air and moisture that clings to their exposed surface reacts with iron to form iron oxide or rust. Read more from this article: http://www.rotaxmetals.net/corrosion-of-metals-how-naval-brass-survives-the-process/.

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Understanding the Metalworking Processes that Make Naval Brass

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Brass is among the few metals that are easy to work and mix with other metals. Made by combining copper and zinc, it is essentially an alloy, but other metals can still be added to the mixture to form variations of it. Each brass variant possesses unique qualities that are needed for highly specific applications.

One variant of brass that has gained popularity over the years that it’s been widely utilized for marine applications is the naval brass. This alloy consists of around 60% copper, 39.2% zinc, 0.75% tin, and a trace amount of lead. Such a combination results in a super-brass, with properties not found in other variants.

The Inclusion of Tin

Tin is a soft, silvery-white metal that doesn’t easily oxidize or corrode. The natural oxide film on its surface allows it to resist corrosion from both seawater and tap water. Like other metals, however, tin is not invulnerable to strong acids, alkalis, and acid salts. But since it is highly resistant to corrosion, it is widely used as plating or coating for food containers or anything that requires exposure to oxygen-containing substances. Read more from this article: http://www.rotaxmetals.net/understanding-the-metalworking-processes-that-make-naval-brass/.

Interesting Facts about Naval Brass and Its Properties that You Probably Didn’t Know

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Naval brass, as its name suggests, was originally meant to be used for water-related applications, specifically sea water. The open waters have high salinity or salt concentration, which can easily damage metals that are not protected against corrosion. Once corrosion starts, it can be difficult to prevent it from spreading throughout the vessel.

It is for this very reason that naval brass was created. The tin added into the alloy significantly increases the resulting metal corrosion resistance, allowing brass to last and endure saltwater for longer.

On top of anti-corrosion, the presence of tin also helps increase naval brass’ resistance to dezincification, a type of corrosion in which only zinc is removed from a material, thereby weakening it and making it prone to damage. According to maritime history, dezincification used to be known as “condensiritis,” and had been the subject of various attempts at resolution. Read more from this article: http://bit.ly/2IM7BNt

Interesting Facts about Naval Brass—Composition, Properties, and Applications

Naval Brass Is Best Used on Boat Fixtures and Other Marine Setti

Anyone who has experienced using brass can tell how malleable, strong, and durable it is. This metal is composed mainly of copper and zinc, but sometimes, a miniscule amount of tin and other metals like lead is added to improve its properties. The ratio of copper to tin varies depending on the metal’s intended purpose. The composition ranges from 55 to 90 percent for copper and 10 to 45 percent for zinc.

As for naval brass, the perfect ratio is around 59% copper, 40% zinc, 1% tin, and trace amounts of lead. Due to its composition, this type of brass is classified under a brass subfamily known as “Alpha Beta” or sometimes “Duplex Brasses”, which are stronger and harder than other brass groups, particularly when it comes to dealing with saltwater. This makes them a perfect material for sea vessels.

Why Alloy Composition Is Important

The reason why brasses are classified into different groups is that each unique composition yields a material of unique properties. This is especially the case with malleability and ductility, two critical properties you can get from brass alloys. The malleability of brass depends on the amount of zinc used. When the alloy contains more than 45% of zinc they are known as White Brass and are no longer workable either in hot or cold.\ Read more from this article: http://bit.ly/2pMLMpS

Naval Brass and Two Other Brass Alloys with Excellent Corrosion Resistance

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Brass is prized for many of its characteristics, including its distinct appearance, machinability, durability, and conductivity. But perhaps the property that craftsmen and artisans consider to be the most important is its excellent corrosion resistance. Through the ages, new brass alloys have been introduced with improved ability to withstand corrosion. This is why brass remains as a preferred material for aggressive working environments and even in marine applications.

Today, there are over 60 types of brass specified by European Norm standards, each with a different composition to suit the specific needs of the user. If you want a material that satisfies the most demanding conditions across many industries, however, here are three of the finest alloys you can get from suppliers like Rotax Metals.

Naval Brass

Also referred to as admiralty brass, naval brass is composed of 30 percent zinc and 1 percent tin. Small as it may be, that tiny percentage of tin is what gives naval brass its most notable property—resistance to dezincification. This is especially true if the copper content is near the top end of the range. Being an alpha-beta brass, naval brass is often cheaper, easier to find in markets, and more workable at high temperatures. Naval brass plates hold up well against seawater and other caustic substances, making it a staple in ship manufacturing.

Muntz Metal

Muntz metal is also a popular material in the shipbuilding industry, although it’s not quite as widely used as naval brass. Its composition of 60 percent copper, 40 percent zinc and a trace amount of iron makes it a little more susceptible to dezincification, particularly in marine environments. This is why Muntz metal is more commonly used only as lining on boats. When treated and protected with iron or zinc anodes, though, it can tolerate a significant amount of dezincification before needing replacement.

Aluminum Brass

Nowadays, aluminum brass is just as important as naval brass when it comes to marine applications. Containing about 76 percent copper, 22 percent zinc, and 2 percent aluminum, this alloy has superior corrosion resistance, too. Aluminum brass sheets, strips and plates are widely used in seawater service and sometimes for production of seawater pipe systems. It is also a prominent material used in Euro coins due to its resistance to tarnishing, as well as its non-allergenic and mild antimicrobial properties.

All brass types are naturally corrosion resistant under normal conditions, but some are designed to be more resilient when exposed to the elements. Consult with your supplier to know which brass alloy works best for your project.

 

About Rotax Metals

Rotax Metals is a trusted supplier of quality copper, brass and bronze products for a number of industries. Founded by Ronald Rosenthal in 1948, our company offers an extensive inventory of competitively priced items along with value added services, such as welding, cutting, forming, and machining. We also provide special services, including polishing, metal shearing, waterjet cutting, metal fabrication through our vast network of resources. Get in touch with us and let our experienced and knowledgeable staff help with your project today.

 

Sources:

The Brasses: Properties & Applications, CopperAlliance.eu

Brass Alloys and Their Applications, TheBalance.com

Why Naval Brass Is Preferred in Ship Manufacturing and Other Construction Projects

A Large Ship Propeller Made of Naval Brass Can Resist Salt Corrosion

Unlike other types of vehicle, sea vessels face one unique, tough challenge–saltwater corrosion. There’s a vast range of substances that can corrode metals, but sodium chloride or salt, mixed with water and other impurities, is different. Saltwater can cause most metals to corrode five times faster than freshwater. Even well-known corrosion-resistant metals like copper, bronze, and aluminum don’t stand a chance against this potent chemical soup. This is why most boats and ships are not expected to last long without regular maintenance and coating.

Thanks to advancements in metallurgy, alloys that have better saltwater corrosion resistance have been discovered and are now widely used in ship construction. One of these alloys is naval brass, a perfect mix of copper, zinc, and tin. It is primarily designed to improve the performance of the outer covering of ships. Read more from this article: http://bit.ly/2DtwVZr

Find Out Why Naval Brass Is Capable of Resisting Corrosion Caused by Salt

A Ship Propeller Corroded by Salt--Prevent Corrosion with Naval Brass

Did you know that the salt you put on your food and eventually into your system is capable of corroding metal? A compound of sodium and chloride, salt can quite be caustic on certain materials. You don’t have to worry, though, because your body does not respond similarly when in contact with salt. (Of course, like with any other food additive, you have to keep your salt intake in check to avoid problems) It’s just that metal and salt don’t mix well together.

Surprisingly, even metals with high corrosion resistance won’t stand a chance when exposed to salt for a long period. You may think that well-known corrosion-resistant metals like copper, bronze, and brass might pull it off but the truth is they, too, will corrode when dipped in salt solution. Read more from this article: http://bit.ly/2C6OT0N