Getting Down to Brass Tacks on Quality

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Brass has a long history as a manufacturing metal of choice because of its
machinability, strength, ductility and corrosion resistance, along with its
relative low cost and broad availability. Its favorable economics are due in
large part to the highly recyclable nature of brass. In fact, ninety percent of
brass sold in the US [from both domestic and international sources] is
recycled. However, the process of recycling of brass has been a growing
challenge in recent years. The chemistry and composition of brass can be
changed over time because of inadvertent contamination of the scrap
stream with inferior quality brass along with other metals, such as steel, tin
or iron. Contamination such as this puts the consistent quality,
machinability and strength of brass at risk.
Complicating potential quality issues with brass is legislation concerning its
lead content. Lead has historically been added to enhance machinability,
up to 3.7% in C 36000, an alloy comprising 80% of brass sold in the US,
commonly used in plumbing for drinking water. This alloy will be markedly
affected by a recent amendment to the Safe Drinking Water Act, restricting
lead content to 0.25% (as of January 2014), similar to a current California
law in effect, AB 1953. The industry is faced with the need to lower lead levels to match those defined by this legislation, greatly affecting the chemical and mechanical make-up of brass. As is true in any industry, obstacles lead to innovation. There are now two
“brass rod” alloys that are closely related: C 36000 and C 36010. The new
alloy C 36010 was created with a lead range of 3.1 % to 3.7 % for those
customers who still need higher lead content for their applications. C 36000
continues to be the standard “brass rod” of choice for customers needing to
have both high machinability and stay within the guidelines. These two
alloys, however, are easily confused; customers now need to specify which
is appropriate for their needs.
In addition, we are seeing increased use of silicon, bismuth and antimony.
While these elements may serve as excellent lead replacements for some
applications, not for all, and when added to improperly separated scrap,
contamination issues multiply. Even when found in trace amounts, brass
from unknown and unproven mills may contain higher levels of lead or
elements like antimony, known to cause cracking post production.
The answer lies in using industry recognized and trusted sources for
supply, having confidence that despite meeting ASTM specs, the chemical
and mechanical specification of the material is known and proven for its
intended purpose. Questionable quality is a risk to everyone in the supply
chain. For the machine shop or manufacturer of parts,
substandard brass translates to difficult machining, costing time, productivity and money.

 

Rejections and additional costs are more likely and perhaps the greatest
risk is that defects and failures could show up when the parts reach the
OEM or even worse, reach a finished product or the final consumer.
Critical failures do occur. While cost is always a factor, the risk of product
failure from questionable material outweighs the lure of low cost metal from
unknown and unproven mills. Only then can the end user be assured of a
level of quality that is built in to the metal so that the risk to the supplier, the
machine shop and the end user is managed and minimized. Admiral Metals
is certainly committed to providing our customers with high quality, proven
brass meeting the most updated specifications from known and reputable
mill suppliers.

For more information about brass quality, call or email us at Admiral
Metals. When it comes to buying metal products, it’s important to us that
our customers have confidence in the brass they buy, in Admiral Metals and in the mills we represent.

Wishing you the very best in business,

Jim B Signature

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