You Get What You Pay For: 5 Reasons Trusts Trumps Price When Purchasing Bronze

Bronze has been both utilized for and in a variety of products throughout history, including tools, weapons and armor. As well, it has been used to cast beautiful sculptures since craftsmen first discovered the practice in ancient Greece. Today, Bronze is ideally used for bearings, bushings, wear plates, heavy duty guides and springs.

Unfortunately, the price of bronze has risen dramatically over the past decade, causing manufacturers, architects and sculptors to seek more economic alternatives. This is due to the fact that copper, a main component of bronze, has become increasingly expensive.

In 2000, copper cost just under $1 a pound. However, as the Great Recession hit in 2007, the price soared to $5 per pound. Even though the price has since simmered down, the metal’s price still hovers around $3 per pound. This 200% increase over the last decade has caused a dramatic effect on the modern use of bronze.

Sculptors, who once used bronze as the main component in their art, have converted to using cheaper alternatives like Aqua-Resin, concrete, Fiberglass, gypsum- and polyurethane-based resins, plaster and terra cotta.

Commercially, the cheaper alternative to using bronze is brass, due to its composition of copper and zinc. However and most importantly, some copper-based alloy such as Aluminum Bronzes offer a combination of mechanical & chemical properties unmatched by any other alloy series.  This feature often makes copper-based alloys the first choice for demanding applications. 

Additionally, industry professionals know that you must trust the metal you are working with. Thus, I’ve come up with five reasons to consider purchasing bronze despite its cost.

1. It contains excellent corrosion resistance – especially in seawater and similar environments, where the alloys often outperform many stainless steels
2. Exhibits good weldability – making fabrication economical
3. Good resistance to fatigue- ensuring a long service life thus saving time & money down the road
4. Some aluminum bronzes exhibit strengths comparable to low alloy steels and many are stronger than most stainless steels. For instance in Bridge Applications – some bronzes thrive on heavy loads, shocks and harsh working environments thus making it a perfect fit for bridge bearings. When lubrication of sliding surfaces is less than ideal, aluminum bronzes are superior to ferrous materials.
5. Non-Sparking Characteristics – Excellent non-sparking characteristics make aluminum bronzes suitable for manufacture of tools and equipment used in the handling of explosives, in mines, petroleum and chemical plants, gas-handling equipment and similar applications.

A Sacrificial Metal: Why Bronze is So Selfless

Consider the following definition of sacrifice from the American Heritage Dictionary: “to sell or give away at a loss.” In accordance with this definition, bronze can be considered a sacrificial metal, in which it offers itself up to serve a piece of equipment that would otherwise be unable to withstand climatic or severe operating conditions.

Last year, I posted a blog titled, “The Bronze Fish,” detailing how aluminum bronzes are naturally suitable for water applications due to their great resistance to water corrosion. When metallurgically bonded to metals such as steel, which is not ideally suitable for water, aluminum bronzes add strength and durability to the part.

Aluminum bronzes are most commonly used in water applications because of their great resistance to corrosion in a variety of water environments. However, bronze does not only work well in various water environments, but it can also be used in rural and industrial atmospheres.

As a sacrificial material, bronze can be utilized anywhere metal is rubbing on metal. Upon being placed between two pieces of metal, usually steel, the bronze acts as a buffer. When the pieces of steel rub together or move, the bronze bearing absorbs the friction. By doing so, bronze accepts the loss of its own metal as time goes on in order for the steel, or the other metal, to continue fulfilling its operational purpose.

The following attributes are just some of the traits that make bronze a successful bearing material:

• Low coefficient of friction versus hard shaft materials
• Corrosion resistance
• Easy and economic manufacturability
• Cost effectiveness and availability
• Ability to absorb friction
• Ductility

But what makes bronze so selfless?

Although there are various compositions for bronze, being an alloy of copper and tin allows the material to withstand many corrosive factors that other metals cannot endure, such as climatic conditions; weather and exposure to rain, wind and sun; pollutants in the atmosphere; heavy loads and increased speeds; and patination.

Overall, bronze takes a licking and keeps on ticking!

HOW TO :: Selecting your Bushing Material

In a perfect world selecting your bushing material could be so easy.  Just imagine....the journal surfaces are smooth and always separated by a full film lubricant.   The materials never experience elastic or thermal distortions and the lubricants have no abrasive particles.  In this perfect scenario, you would only need to consider selecting a suitable material by it's strength qualities and take no other factors into consideration.

Sounds great, except, that scenario does not exist.  The reality is - a bushing can distort, journal & bushing surfaces can not be made perfectly smooth, and the bushing may be occasionally "starved" of lubricant. With the real factors in mind, the choice of good bushing materials in conjunction with bushing design & an appropriate lubricant are essential in how to select your bushing material. 

Where do you start - what are the desired material qualities?
After years of testing and trials, experience has shown us that good bushing material has certain general desired qualities:

• Score Resistance - contains antiweld / antiseizure characteristics
• High Compressive Strength - can carry a load without disintegration
• High Fatigue Strength - can provide a decent service life under stress
• Deformable - the material will permit to yield without causing failure
• Corrosion Resistant - reduces or eliminates wearing away caused by various acids
• Low Shear Strength - resists movement of one layer of the material in respect to the other
• Structurally uniform - a sound, non-porous surface that maintains full-film lubrication
• Low Cost & Availability - this one is self explanatory!

Since no single material comprises all of these desired qualities, you will most likely have to compromise on one or more of the above qualities. For example, one material might exhibit great fatigue strength but have poor deformability. 

How about Cast Bronze?
In general Bronze offers a great compromise with respect to the desired qualities for a good bushing material.   Take a look:

Cast Bronzes (example: C93200, C83600, C90300, C93700, etc)

Bronze bushings are suitable for a wide range of applications.  They have a great number of benefits that a great number of alloys don't offer.  They have great strength and can be economically produced in a variety of shapes and sizes.  There are extremely reliable in the sense that they can made as a single, solid unit with no bond or liner to fail.  The high thermal conductivity of cast bronzes is an advantage in taking heat from the bushing surface, which tends to prevent "hot spots.  However, despite the benefits of cast bronzes as a whole, it is extremely important to select the right alloy for the job.

There are many Cast Bronzes - which one do I choose?
This is the #1 question our sales group will typically receive from our customers.  But the choice always boils down to one question -- What is the bushing being used for?   When you take four popular bushing alloys and line the characteristics up against one another you see how one alloy might work better than the other.  Take a look below at the characteristic box:

Now the above box is by no means comprehensive and does not include other material features such as wear resistance or machinability rating, etc.  However, it is helpful to see the popular bronze alloys side by side showing how one alloy might be preferable to your application over another alloy. 

Oil Prices Dropped - Now What? 

 

Recently, over food and coffee I had the pleasure of sitting down with some businessmen from overseas.  As you can guess the big topic of discussion was the sharp decline in the price of oil.  For those of you who may not be following the topic closely – oil prices have drastically declined over the past 3 months causing much speculation and concern.  So much so, that there are some who are scared that the US will again enter into a recession.   Of course, I can understand that, as the price of oil has plunged by more than half since June 2014, reaching levels last seen during the depths of the 2009 recession.  

With everyone seemingly on the edge of panic mode, I had to ask myself, will this really lead to a recession?  What does this mean for manufacturing?  Is it possible that the lower oil prices can actually increase business?

Well to answer that question, I did a little research and took a look back to see who suffered as a result of rising oil prices.  It turns out, there were three major areas domestically affected when the prices rose up around the $100 barrel mark.  

The first area was Consumer spending.  I know - this one is obvious.  Consumers as a whole backed off from unleashing the full potential of their annual budgets.  They were generally conservative due to the rising costs of transportation, food, and energy costs they incurred to run their businesses and households. The consumer would back off on driving.  Car production suffered.  The consumer backed off on shopping.  Stores backed off on expansion and building.  Consumers back off on travel.  The airline industry backed off on fleet expansion and operated conservatively. Essentially, It was one big fat domino effect.  Everyone was raising rates and costs, thus it all affected the general consumer. 

The second area was the Unemployment rate. I was surprised to learn that just a $20 increase in the cost of a barrel of oil cuts 0.4 percentage points off growth in gross domestic product and increases unemployment by 0.1 percent, according to a study, by the Energy Information Administration, part of the federal Energy Department.  You see, when a business has to adjust their budgets for higher energy costs and lower consumer demand the result is they lay people off.  Businesses just have less money to give to employees in wages.

And the third area was the Manufacturing sector.  In just about every area of the Manufacturing sector the cost to do business increased as transportation and energy costs rose.   The businesses absorbed the cost increases, which in some cases led them to make the choice of higher end-item prices to offset the increase, which subsequently led to decreased demand for their products. Essentially, they had to rob Peter to pay Paul.  

Now that we have briefly looked at what happened when the oil prices skyrocketed, let’s look at what should happen to these three areas now that the oil prices have tanked.  

In June of 2014, when oil cost $107 a barrel, U.S. employers added a healthy number of jobs – 267,000. Now, with oil below $50, hopes are rising that hiring in the United States is poised to intensify.  Goldman Sachs forecasts that if oil stays near its current price, the economy will add 300,000 more jobs this year than if the price had remained at its June level.  From gas-station prices to utility bills, consumers and businesses are now enjoying savings on basic energy costs. It means more people can splurge on purchases from clothing and appliances to vacations and dinners out. That stronger demand will likely require some businesses to step up hiring, which would circulate more money through the economy and perhaps fuel further job growth.

Due to lower oil prices, it is predicted that the Consumer will have a net gain increase by $920 per year for each household. The average propensity to consume is around 90 percent, so the average US household could spend around an additional $825 per year.  According to Bloomberg Businessweek, “Several districts “expect somewhat faster growth over the coming months,” the Fed report showed. “Payrolls in a variety of sectors expanded moderately” while “significant wage pressures were largely limited to workers with specialized technical skills.”

So if it’s true that Consumer spending and employment is looking strong than can't we expect the Manufacturing sector to fair well during the decline in oil prices.  I would even dare to say, the manufacturing sector might actually thrive.  If Consumer’s spend, businesses hire.  If Consumer’s travel, auto manufacturing increases and so does the airline industry.  In fact, Bloomberg Businessweek just reported that the production facilities of Boeing Co. (BA:US), the largest U.S. exporter, cited “strong” commercial aircraft production and “sizable” order backlogs.  If Consumer’s spend, then theoretically shouldn't the aerospace, automotive, marine & naval and the welding industry follow suit?   

Personally, I think the manufacturing sector is at a pivotal moment.  The "powers that be" can operate conservatively OR better yet...they can be forerunners, leading the way for growth and opportunity in the US.  It seems that all the signs point to growth and stability.  But nonetheless, I'd love to hear from my readers as each of you have a unique perspective on how it will or will not affect you.  It will be interesting to see how 2015 pans out and I'm sure this won't be my only post about the topic.  

PS:  It's great to be back at Atlas Bronze & in the bronze business again!  

The Bronze Fish

Metal is notorious for corroding in water applications.  The power packed combination of moisture, oxygen and salt, especially sodium chloride, is more deadly to metal than rust.  It corrodes or eats away at the metal by weakening it and eventually causing it to fall apart.  And if the metal is submerged in a salt water environment than count on your metal corroding five times faster than if it was in fresh water.

Considering we rely on metal in just about every "water-related" application out there, the above statistics sound a bit bleak.  Let's see, we need metal in plumbing, water filtration, sewage plants, hydro-electric power, oil & gas platform parts in the ocean, engine cooling, refrigeration, irrigation and the list goes on and on.  How could the world's economy and infrastructure have survived if metal wasn't used in water applications?  Well, since you and I haven't heard about the world's ongoing struggle to find a metal for water applications that means a solution must have been found. 

Steel in Water?

Traditionally, steel is not seen as a suitable metal for water applications.  Why?  Remember that moisture is highly corrosive to most metals including steel and zinc.  However, steel is indeed used in water applications. 

So, how do you get around the moisture problem?   OK, so here is my inner Comic Book geek coming out.  There is this character called The Green Latern.  For a visual reference see below:

The Green Latern is a unique comic book character.  He is green, flies through the air and creates objects with a special ring.  BUT what sets him apart from a lot of other Comic Book characters is his protective suit.  You see, he doesn't "suit up" like Batman or Superman.  Instead his protective suit is bonded to his DNA makeup.  So when he senses danger the suit magically appears on this skin. 

So what does Steel have to do with Green Latern's magic suit?  In order to make steel suitable for water applications, there is a process called Hot Dip Galvanizing.  This is where a "layer or protective suit" is metallurgically bonded to the steel ~ not added like Superman or Batman's suit.  This bonded layer is a complete, uniform coating that adds strength (apprx. 3600 psi) and long term durability to the part.

However before you go and select Hot Dip Galvanizing Steel (HDGS) as your "go to water metal", beware of some of the disadvantages.  You must know what type of water the part will be submerged in, such as; pure water (distilled or de-ionized water), fresh water, or seawater. Each water environment has different mechanisms that determine the ultimate corrosion rate.  For instance, studies show that HDGS will corrode up to ten times faster in a pure water environment than in a fresh water environment.

Also, one of the most corrosive areas for HDGS is in Agitated Waters, such as; wash zones and tide lines.  The agitation accelerates the corrosion rate of the zinc.  Often the “washing” motion removes the passive scales which are forming on the surfaces, exposing fresh zinc which tries to redevelop more scales/patina. This leads to rapid erosion of the zinc coating resulting in increased corrosion rates.

So what are the alternatives?

Introducing The Bronze Fish

Well by now I'm sure most of you were beginning to wonder what is this Bronze Fish all about.  After all, that's the title of the blog post.  While it's true that other metals can be used in water, there is a Bronze Alloy group that is naturally suitable for water applications.  They are chemically and mechanically designed for water (and of course other applications as well).   Hence, the Bronze Fish reference.  

This group is the Aluminum Bronzes.  

Aluminum Bronzes are most commonly used in water applications because of their great resistance to corrosion in a variety of water environments.  This makes them preferable to other engineering materials.  The Aluminum Bronze group contains a variety of choices,  but for the sake of time I will highlight three:

1. C63000 Nickel Aluminum Bronze
2. C95400 Aluminum Bronze
3. C95800 Nickel Aluminum Bronze 

 

The 630 Fish - the strong & tough fish

C63000 Aluminum Bronze is an extruded or forged Wrought Alloy that contains Nickel (nominal 5%). As an aluminum bronze, C63000 has an excellent resistance to salt water corrosion and displays exceptional strength and toughness as well.  C63000 is typically used where higher mechanical properties are required.  It is used in equipment for marine applications, such as:  valve stems, high strength bushings, valve guides and seats, gears, cams, ship propellers, as well as propeller nuts and shafts.

 

 

The C95400 Fish - the popular fish

C95400 Aluminum Bronze is a Cast Product that is considered the most popular of all the Aluminum

The "Nemo' fish

Bronzes.  It is regularly stocked in a variety of shapes and sizes, such as, Solid Bar, Cored Bar and Plate and Rectangle; thus making it the "go to" Aluminum Bronze. C95400 is suitable for fresh water and salt water (if heat-treated) applications as well as agitated waters.  In fact, C95400 is nearly impervious to attack from seawater when properly heat-treated.  However note that improper heat-treatment of C95400 castings can result in a finished product susceptible to a unique form of galvanic corrosion commonly called de-aluminization.  

 

The C95800 Fish - the dirty fish

C95800 Nickel Aluminum Bronze is a Cast Product that also contains 5% Nickel (much like C63000). However, unlike C63000 it contains slightly less Aluminum & Copper and a bit more Iron. Additionally, due to it's Method of Manufacture (or the way its made) it possesses different mechanical properties. 

C95800 as a Centrifugal for pumps will stand out as being ideally suited for  saltwater, as well as brackish or dirty water, waste water and pollution control applications.  The overall corrosion / erosion resistance this alloy displays
has been deemed far superior to stainless steel -- and costs less!! (always a benefit) 


It is amazing how Bronze stands out against the "big guys", like Steel and Stainless Steel in certain environments and applications. Even though annual Bronze consumption accounts for such a small percentage of all the metal consumed in the world - it is clear that Bronze has a major part to play in the Metals Industry.  I am finding that it is a unique, diverse and adaptable underdog. 

Until next time...enjoy your week!

What to know when buying a Wrought Product versus a Cast Product

Today's blog is brought to you by one of our very own, Eric Grabowski.  Eric has been in the Metals Industry for over 30+ years (although he REALLY doesn't like me saying that...he says it makes him feel old!) and with the Atlas Bronze family for 15 years. We are lucky to have Eric as he is our Go-To guy when it comes to technical advice on Made to Order parts.  He knows his metal!

Buying a Wrought Product

 

We have a number of customers who are accustomed to buying steel, stainless steel, brass, and aluminum on a daily basis.  When they buy this material they are used to ordering the size they need based on a set tolerance. Steel, stainless steel, brass and aluminum are made by either extrusion or drawing, so when you buy one of these products the outside diameter, thickness or width will typically have a tolerance that is plus (+) and minus (-). 

For example:

You need:  1" diameter Brass Rod (Wrought Product)
Tolerance: plus (+) and minus (-)  tolerance on this bar will be +/-.005.  
This means:  Diameter size will fall between .995" diameter and 1.005" diameter

Buying a Cast Product

Now say that same customer receives a request to purchase a Cast Product.  They will quickly find out that the material tolerance will follow a different set of rules. You see, with Cast Bronze Products (most popular alloys being C93200 Bearing Bronze and C95400 Aluminum Bronze) if you were to order that same 1" diameter it will typically have a tolerance over sized by as much as .090" on that diameter.

For Example:

You need:  1" diameter Bronze Rod (Cast Product)
Tolerance:  a minimum of .070" over sized
This means:  Diameter size will be at a minimum of 1.070" diameter

So what's the difference?

It is simply that Wrought Products hold a plus (+) and minus (-)  tolerance.  The bar could fall slightly above or slightly below the desired size.  On the other hand, Cast Products offer additional stock that enables a customer to finish to the desired size.  In Cast Products that additional stock added will also apply to Cored Bar and Rectangle / Plate stock. There will be extra stock added to the Outside Diameter, the Inner Diameter and on a Width and Length. 

Why knowing your finished dimensions when buying Cast Products will save you time and money?

When a customer is buying a Cast Product, we always ask, "What are your finished dimensions?".  We typically ask this because we look at all the available sizes we have in our inventory and select a size that will finish to the customer's needed dimensions.  The goal is to save the customer money on the amount of scrap generated and time in the amount of machining. Knowing a customer's finished dimensions on rectangular cut plate is especially important. We can consider the thickness, width and length and make an allowance for clean up based on the finished size of all 6 surfaces on the rectangle.

There are other reasons we ask for the finished dimensions - especially on longer lengths. As you increase in length with a Cast Bar Product you run the risk of that bar not remaining perfectly straight or flat.  This is crucial if that customer will ultimately need to machine the entire bar.  So we make larger allowances based on the length of a finished piece to ensure the customer will finish to those desired dimension. 

As a rule of thumb regarding any bronze, make sure you communicate what you are finishing to as it provides important information, that will ultimately save you time and money. 

Gallery of Atlas Bronze Selfie's

Pedro & Ruth (Pedro has been with Atlas for over 10 years, he is a Jack of All Trades and helps keep our Warehouse Operations running smoothly!  Chances are Pedro has cut your material at one point or another :)

Nancy, Jason & Ruth - Nancy & Jason work in the Trenton location and are the anchors in that ship.  Jason is our Warehouse Manager and Nancy is basically his right hand man!

Chris, Jason, Melissa & Ruth - Chris is our Vice President of Operations...I affectionately refer to her as MOM, as she is the wisest woman in Metals I know!  Melissa is in our Sales Department and has been with us for over 5 years.  She is one of the sweetest and caring co-workers!

Katie, Anthony, Eneldo & Ruth - Katie & Eneldo are Sr. Sales Rep's and are amazing at their job.  I sit in between them at the office, so I learn a lot to say the least.  And Anthony in the back is our IT/Project Manager who could basically work at the Apple Store :)

Fancy Nancy & Ruthie Toothie (our nicknames)