Research Projects

Applications for Induction Motors with Die Cast Copper Rotors

The Copper Based Casting Technology Program demonstrated the feasibility of using die-cast copper rotor motors, which are now available from a number of sources now that the die casting manufacturing issues associated with the high melting point temperature of copper and resulting short tool life are understood. Tool life has been extended and cost effective die casting is now available.

Copper die cast rotor induction motors offer the potential for improved efficiency, lighter weight and lower operating temperatures than conventional aluminum die cast rotor induction motors. These benefits are particularly important for larger motors and for scaling up copper die castings from today’s state of the art of 25 pounds of copper rotor to motors that have more than 200 pounds of copper. This capability opens up new opportunities for this technology in military, as well as non-military operations.

The following programs are evaluating the benefits of the copper rotor-motors versus traditional aluminum induction motors in various applications:

Antimicrobial Applications

The antimicrobial properties of copper have been well established through extensive laboratory studies by various researchers. However, its application in real word settings has not been thoroughly tested. In 2006, two federal research programs were launched to investigate the benefits of antimicrobial copper surfaces in two distinct settings: frequently touched surfaces in hospitals, and within heating, ventilation, and air-conditioning system (HVAC) components.

Copper Air Quality

The Copper Air Quality Program will compare the antimicrobial efficacies of aluminum and copper HVAC system components (heat exchanger fins and drip pans). The program will evaluate copper and aluminum units in both laboratory and real world systems. In the laboratory, it will test the rate of growth of biofilms on the heat exchanger fin surfaces as well as the concentration of microbes in air downstream of the heat exchangers. The field component of the program will evaluate and compare the concentration of microbes in the indoor air of buildings that utilize either copper or aluminum finned heat-exchangers. The energy efficiency of each of these systems will also evaluated.
Copper Touch Surfaces
The Copper Touch Surfaces Program will determine the degree to which copper, brass and bronze surfaces decrease bacterial contamination on frequently-touched surfaces in hospitals. Surfaces that are being manufactured with copper alloys for this study are typically made with stainless steel or plastic, neither of which have demonstrated efficacy in controlling pathogens. The program will also investigate the impact of copper touch surfaces on infection rates and microbial transmission from the environment to hospital patients.