With the introduction of the Safe Drinking Water Act in 2011 the water distribution systems of our country have gone through significant transformation. This has been the change that finds us providing our new ECO BRASS®/ECO BRONZE® lead-free product lines. Complying with the critical need to remove all drinking water from lead exposure. As explained by Larry Muller, our Director of Metallurgy and Technical Services, “ECO BRASS/ECO BRONZE is Not Your Father’s Silicon Brass.”
To paraphrase that classic Oldsmobile advertisement from a couple of decades ago, ECO BRASS®/ECO BRONZE® is not your father’s silicon brass. It’s an engineered silicon brass with a strong manufacturing history. ECO BRASS, with the UNS number C69300 for rod, and ECO BRONZE with UNS Number C87850 for castings, is very different from existing copper silicon alloys because of its chemistry and microstructure. They share one composition which can produce rod, forgings and castings which are machinable, strong, corrosion resistant, lead-free, and have proven to be a great alternative to the standard C93200 leaded tin bronze alloy in wear applications.
The world has changed dramatically, especially if you are in the drinking water distribution business, and we need to either become part of the solution, or join the slide-rule or buggy whip manufacturers that have a bleak future. The passage of state and federal legislation over the last few years which essentially eliminated the use of lead in drinking water fittings and fixtures, in combination with deteriorating water quality in increasing parts of the country causing field failures in poorly made imported fittings created an urgent need for a lead-free, high performance brass alloy.
The literature, manufacturing experience and anecdotal evidence that exists for silicon brasses like C69400, C87500, C87600 and C87800, reflect the strengths and shortcomings of a class of alloys which were created a long time ago. Those alloys filled an important performance need in many areas but also created a mind-set about what to expect from anything with the label “silicon brass”. The performance summary below serves to reverse those biases by showing how and why ECO BRASS/ECO BRONZE is different in almost every key area that’s important to producers and users.
ECO BRASS/ECO BRONZE advantages:
- Performance in machinability, forgeability and castability rate from 70% to 100% of the best existing alloys
- Not as prone to cracking during machining like other lead substitutes such as bismuth;
- Strength is like stainless steel but with much better machinability
- Resistance to dezincification is as good as bronze
- Stress corrosion cracking resistance is as good as low zinc alloys
- Cost competitive as a foundry alloy compared to bismuth brasses and some traditional silicon brasses
Those attributes are based on over 18 years of manufacturing and field experience in all product forms. ECO BRASS/ECO BRONZE are in the following standards or meet the requirements of:
ECO BRASS PRODUCTS
ASTM B371, ASTM B124, ASTM B283
NSF 14, NSF 61, NSF 372
ECO BRONZE PRODUCTS
ASTM B30, ASTM B505, ASTM B584, ASTM B806
AWWA C502, AWWA C700, AWWA C701, AWWA C702
NSF 14, NSF 61, NSF 372