Environmental Corrosion Risks to Outdoor Structures Made of Bronze Bars


Although bronze bars and other copper alloys are highly valued by artisans and architects for their decent resistance against corrosion, they can still be subject to tarnishing and discoloration. This is especially true for copper-based metals placed outdoors and are constantly exposed. Common types of bronze like architectural bronze, commercial bronze and statuary bronze, for instance, have particularly poor resistance against some elements found naturally in urban settings. Under such conditions, a bronze structure will deteriorate gradually over long periods of time.


If you want your bronze craft to retain its distinctive appeal and hold up against corrosion, you need to be aware of some environmental risks they could face. Be sure to take precautions against these problems.


Urban Pollution


Heavily populated cities have a high concentration of pollutants, especially sulfur compounds, in the atmosphere. With continuous exposure, you can expect bronze to corrode at higher rates. It usually begins with the appearance of patches of light green on horizontal surfaces where rains and water run-off flow through. Over time, the effect spreads over the entire surface, making the metallic construction appear bright green instead of reddish gold.


Bird Droppings


Bird droppings, as well as other animal droppings, are virtually unavoidable for fixed outdoor structures. They not only obscure the appearance and message of your installation, but they unfortunately also tend to be highly acidic in nature. When they accumulate on the surface, they accelerate localized corrosion and deterioration. The bronze will start to turn darker, and without applying special cleaning procedures, the metal will eventually take on a light green color.


Plant Debris


Decaying plant debris such as leaves, cones, needles, twigs, bark, seeds and flowers may create quite a beautiful scene during autumn, but they can cause considerable damage to bronze. This is because the ammonia produced naturally when plants die can darken the metal. In fact, ammonia in chemical form is used by many metal workers to produce an artificial patination on copper, brass and bronze.


The good news is that you can protect bronze statues or architectural structures by applying coating systems and coating additives. Some great examples of basic coatings include nitrocellulose, acrylic, epoxy, silicone, alkyd, urethane, cellulose acetate butyrate, vinyl and polyvinyl fluoride film. Coating systems can make bronze much more resilient against humidity, pollution, sunlight, abrasion, and the regular wear and tear.


Note that coatings differ in terms of resistance they offer against certain elements. It is therefore ideal to ask suppliers, such as Rotax Metals, whether finishes were already applied to the raw material. This way, you can determine if applying coatings or additives to bronze is necessary. Remember as well that protective coatings need to be reapplied once they wear off to preserve bronze.


About Rotax Metals


Founded by Ronald Rosenthal in 1947, Rotax Metals is now a renowned supplier of high quality copper, brass, and bronze products for a variety of industries. We offer an extensive inventory as well as special services. As a family-owned business, we make it our mission to provide great customer service while we assist you with all your metal needs.




Protecting Outdoor Bronze Sculptures from Corrosion, CorrosionPedia.com

Clear Organic Finishes For Copper and Copper Alloys, Copper.org


Industrial Benefits of Bronze Bars, Tubes, and Sheets—The Properties that Set Bronze Apart


Bronze is one of the most important metals ever discovered. In fact, it is so important that an entire age in history was named after it. An alloy of copper and tin, bronze is a favorite material for making a wide range of items, including weapons, farming tools, bells, and even coins. Today, bronze is wielded for various industrial applications, and for the following good reasons.


Corrosion Resistance


Because bronze is an alloy of two non-ferrous metals—meaning it doesn’t contain iron, which reacts with oxygen to form rust—it naturally resists corrosion. Instead of forming rust (iron oxide) upon contact with oxygen molecules, it forms a protective outer layer, called patina. This process, called passivation, is unique to all non-ferrous metals. As a result, bronze makes a perfect material option for applications that involve exposure to oxygen-containing moisture.


Coefficient of Linear Thermal Expansion


There are many ways to determine a metal’s resistance to heat. One is determining its coefficient of linear expansion or the length by which it expands after being exposed to extreme heat. Bronze has a coefficient of linear expansion of 17.5 to 18. It may look high but it’s actually low that is five points higher than that of concrete, a material that is virtually unyielding to heat. In other words, bronze is one of the best materials for applications that involve exposure to high temperatures.


Wear and Tear


If you look inside an engine, you will see bearing and gear components that are made of bronze. While other metals may have the strength to withstand the speed and pressure required to power engines, very few metals like bronze can actually sustain minimal wear and tear over time, allowing it to last for many years with minimal maintenance. Machines with bronze components, therefore, need constant maintenance and replacement parts.




Generally, copper alloys have excellent machinability. This means that they can be cut easily to suit specific or complex mechanical or structural designs. Unlike steel, which requires just the right amount of carbon molecules to allow for machining, bronze remains highly machinable at various mixtures of copper and tin. It’s no wonder many small machine parts and intricate tubes and bars are made of bronze.


Ease of Welding


Unfortunately, not all metals can easily be welded to another metal. Some even don’t join no matter how you fuse them. Welding is an important procedure in machine design and construction because it helps connect metals securely and fast. Instead of smelting or casting them to form one object, you can simply connect their ends or sides onsite through welding. Bronze is known for its high weldability. It is easy to braze and solder as well.


Whether you are a machine designer looking for the best metals for your upcoming projects or an artisan who is fascinated by the beauty of copper alloys, bronze can be your best bet. You can find high-quality bronze bars, sheets, and tubes in reputable suppliers like Rotax Metals. It always helps to find a supplier that has already partnered with successful builders, designers, and suppliers across North America for many decades.


About Rotax Metals


When it comes to metals, particularly copper, brass, and bronze, Rotax Metals is your most reliable supplier. We started our business in 1948 and since then we’ve provided the highest quality metals for all kinds of project across North America. We customize machine parts, too. So whether you are a builder, supplier, or artisan looking for the best copper alloys, you are most welcome to check out our inventory and find the metals you need.




Infographic: History of Bronze Timeline, Makin-Metals.com

Coefficients of Linear Thermal Expansion, EngineeringToolbox.com

Copper and copper alloys, Twi-Global.com

Bronze Bars Are the Perfect Material for Sleeve Bearings in Machines


For the most part, machine makers have tried to find primary materials that would impart high performance, stability, and cost-effectiveness on their equipment design. However, some metal workers tend to avoid working with bronze bars, not because they find it hard to work with or they find it inferior to other alloys, but simply because they assume that bronze would be more costly.

This is rather unfortunate, as bronze is the perfect material to fabricate sleeve bearings for industrial machines. While it is true that copper, the primary component in making bronze, is costly, those that are made into bronze are typically priced 50 to 70% off the price of the initial copper bar, depending on the point of its manufacture.

Why Choose Bronze for Bearing Applications?

With the famous misconception about bronze’s price out of the way, it is easier to market bronze bars as the ideal primary material for fabricating an ordinary sleeve bearing. Though sleeve bearings are typically small, its function in ensuring the smooth operation of a complex machine is guaranteed. Read more on this blog: http://bit.ly/2wximgZ

Bronze Bars Lend an Industrial Look to Your Home

Interior design trends are constantly evolving, showcasing one savvy motif after another. When it comes to modern home styling, nothing beats the timeless allure of properly-matched and expertly-crafted metal fixtures. If you’re after a bold but conservative look for your abode, go for the charm and dark hues that only bronze can bring.

Continue reading

How to Efficiently Work with Bronze Bars and Other Brass Materials


Jewelry makers absolutely love working with bronze, and not only for its versatility and flexibility as a metal, but for its aesthetically pleasing look as well. Combined with the right techniques and designs, bronze is a jewelry maker’s dream.

If you’re just about to foray into this venture, do yourself a favor by knowing how to best handle the material so you can reap the most benefit from it.

Bronze Basics

Bronze is largely considered to be a great substitute for gold, particularly the 10 or 14 carat type, and mostly because of its similarity in tones. An alloy composed of copper and tin, bronze is very easy to shape and mold, given proper exposure to the right temperature or force. Read more on this article: http://bit.ly/2rF9nLm

A Profile on Bronze Alloys for Businesses

Although bronze itself is an alloy of copper and tin, there are many bronze alloys whose properties change as other metals are added to it. If your business uses bronze in its products, check this guide to confirm you’re using the ideal bronze for every project.

Leaded Tin Bronzes

Bronze with a small percentage of lead is widely used within industry. Typically, it’s used as bearings, railroad components, and in structural castings. This is because leaded tin bronze has antifriction properties and a durable nature. Plus, if you need tightness and machinability, this alloy is a good choice for your business.

Continue reading

Up Close and Personal with Architectural Bronze

Recognized among metal workers by its alloy code of C385, architectural bronze has truly made a name for itself in terms of versatility and reliability. It is made of approximately 57% copper, 40% zinc, and about 3% lead.

Excellent Physical Properties

 Fabricators and sculptors adore this alloy because of its high machinability rating. When it is worked at high temperatures, such as with projects that require forging and pressing, it is elastic enough to be shaped into any form as one pleases. This is why artists can bend and shape this bronze into flowers, leaves, vines, and more. Aside from that, C385 is resistant to the effects of industrial and marine atmospheres. It will not corrode easily when it comes in contact with weak acids, thus making it ideal for outdoor decorations.

What Should Be Avoided

 Though it is a very resilient copper alloy, architectural bronze still exhibits physical limitations. For instance, if this metal is to be used on outdoor structures like monuments, gates, posts, and the like, care should be taken against exposure to acid rain and bird droppings. For indoor installations of bronze, such as stair rails, door knobs, and similar, avoid using ammonia-containing products when cleaning them.

Should you need more data about the strengths and limitations of bronze bars, sheets, tubing, or other forms of brass, don’t hesitate to reach out to experts. These metal suppliers possess years of experience in providing their clients the right types of alloys that best fit their needs. Whatever size or gauge you require, they will most certainly have it in stock.