Niobium Alloy Key to Boosting WEG Axial-Flux Motors by 6.7%

When WEG went looking for ways to improve the efficiency of electric motor drives, they turned to CBMM, a leader in niobium alloy development. The two formed a partnership and in the process, found a way to boost the performance level of the latest WEG axial flux motor by 6.7%. In the world of electric motors, a 6.7% performance level is quite significant. Furthermore, the new, niobium-alloyed motors were able to reduce overall losses by 53% as compared to similar electric motors made from standard, electric steel.

WEG’s latest axial flux motor was created with the help of CBMM and their niobium alloy research. Image used courtesy of WEG

 

The Partnership

WEG has been producing electric motor drives since 1964. Their focus has been on improving the efficiency of electric motors, particularly in the realms of decreasing overall energy usage and increasing the life of motors. As part of a multipronged approach to improving efficiency, they turned to CBMM to improve some of the metallurgical properties of the alloys used to produce their electric motors.

CBMM is a world leader in niobium production and marketing. Starting as a mining company in 1955, CBMM has expanded into research and development, metallurgy, ceramics, and several other related industries.

 

Why Niobium?

Niobium adds quite a few key benefits to the production of electric steels or the steels used in electric motors and other appliances. It is typically a small additive, on the order of thousandths to hundredths of a percent of the electric steel alloy, but its impacts are great.

First, niobium can boost the magnetic properties of the motor. The laminate structure found in motor magnets, transformers, and other such components often suffers losses due to eddy currents. Niobium additions reduce the eddy currents while raising the magnetic flux. Better magnetic properties mean reduced energy losses.

Second, even small additions of niobium can increase the thermal conductivity. This means the heat generated in the motor is more quickly dissipated, leading to longer motor life. With the proper designs, it also means the motor casing, designed with fins to dissipate heat, can be made smaller and lighter.

Third, niobium alloys have better wear resistance and also dampen vibrations. Wear surfaces last longer, and the motor runs quieter and more consistently. Vibrations and noise in a motor are the audible indicators of energy loss, as some of the energy is being converted into these pressure waves. Dampening vibrations also extend the life of bearings and wear surfaces, as the wear is even.

 

Efficiency is Good Thanks to Niobium

With such a large efficiency increase, these motors will quickly become popular with industries that run on tight margins, where saving utility expenses will have a large impact. The compact size and vibration-limiting properties will also be of value, leading to compact, long-lasting installations.

The larger impact of using niobium as an alloying element will continue to be felt throughout industry. Many metals manufacturers are turning to transition metals and even some rare earth metals in small quantities to tailor alloys for more specific purposes. The gains found by adding niobium to these motors will inspire other engineers to look more closely at the metallurgy going into components, rather than only the mechanical design of components.