Industry Braces for Showdown Between Copper-Brass and Aluminum: Are Charge Air Coolers Entering the CuproBraze Age?

    NEW YORK--Dec. 16, 2002--It often happens that one materials system replaces another.
    Indeed, the prehistoric ages of mankind are named for the predominant materials technology -- including the Stone Age, the Copper Age and the Bronze Age, which were followed by the Iron Age in historic times. A comparison of the mechanical and thermal properties of copper and brass against those of aluminum suggests that the automotive industry is at the dawn of a new age in mobile-heat-exchanger design.
    More than 10 years ago, the International Copper Association (ICA) responded to the industry need for stronger heat-exchanger materials by initiating research that culminated in the discovery of CuproBraze technology, now applied globally in the manufacture of highly advanced products. And ICA reports that brazed aluminum and CuproBraze materials may be headed for a showdown.
    Although nearly all charge air coolers (CACs) for heavy-duty trucks currently are made from aluminum, aluminum CACs barely meet today's cooling-design criteria and durability requirements. CuproBraze technology, on the other hand, allows for the design and manufacture of copper-brass CACs that not only are cost-effective and comparable in weight to their aluminum counterparts, but also outperform them in the criteria of cooling power and durability.
    Aluminum places severe constraints on the design of heat exchangers, because it loses strength in a dramatic fashion at elevated temperatures. Furthermore, the precipitous drop in yield strength prohibits operation of aluminum CACs at elevated temperatures. Fatigue fracture of aluminum becomes aggravated at temperatures as low as 160 degrees Celsius, and above 200 degrees Celsius, the material rapidly deteriorates.
    Copper and brass, by comparison, maintain their strength at temperatures more than 100 degrees higher than the failure temperatures for aluminum. Copper melts at 1083 degrees Celsius, while aluminum melts at 660 degrees Celsius. Copper-brass is twice as strong as aluminum at room temperature, five times as strong as aluminum at 200 degrees Celsius, and there is no comparison possible at 250 degrees Celsius. As a result, copper-brass CACs can run at higher temperatures and remove waste energy at a higher rate than aluminum CACs.
    In the laboratory only a few years ago, CuproBraze technology is now employed in the mass manufacture of products internationally. The full potential of copper-brass CAC designs is just beginning to be explored in practical designs. Already, the performance advantages, in terms of cooling, are indisputable. And new designs are appearing on a regular basis.
    Further information regarding the CuproBraze process can be obtained from the International Copper Association (ICA) by calling Anthony Lea, (212) 251-7240.

    The International Copper Association, Ltd. is the leading organization for the promotion of the use of copper worldwide. The Association's twenty-nine members represent about 80 percent of the world's refined copper output, and its six associate members are among the world's largest copper and copper-alloy fabricators. ICA is responsible for guiding policy, strategy and funding of international initiatives and promotional activities. With headquarters in New York City, ICA operates in 28 worldwide locations through a network of regional offices and copper development associations.