Automotive Engineering - October 2023 - 26

Magnet selection
for cost-optimized
MOTOR DESIGNS
MQ1 magnet
grades offer
several unique
advantages in
various motor
applications,
including for
automotive
accessories.
MQ1 magnets are particularly suitable for demanding applications such as
automotive accessories and home appliances.
I
sotropic bonded NdFeB magnets, colloquially termed MQ1, offer
several unique advantages in various motor applications. These
include being free of heavy rare-earth materials, providing high
yield in near-net-shape magnet production, allowing tailored
magnetization profiles for optimal magnet performance due to their
isotropic nature and exhibiting high resistivity to eliminate eddy current
loss in the magnet.
MQ1 magnets also exhibit excellent thermal characteristics, maintaining
their performance across a wide temperature range. These
features make them particularly suitable for demanding applications
such as automotive accessories and home appliances, where motors
can either experience significant temperature fluctuations and/or
require superior energy efficiency.
Which grade is optimal?
There is a wide range of MQ1 magnet grades; hence for any new design,
the first question a designer has is which grade of magnet
should be chosen to arrive at cost-optimal motor?
Several aspects should be taken into account when choosing the
magnet grade for a new design: 1) affordability and dependability of
raw materials; 2) the magnetic properties at both room and high temperatures
and 3) the magnet's stability, specifically the potential for
flux loss at high temperatures. All are important factors to consider.
26 October 2023
Impact of raw materials: Fluctuations in the pricing of
raw materials inevitably impact the cost stability of
NdFeB magnets. As the originator of the raw material
for the MQ1 magnet, Magnequench possesses a profound
understanding of rare-earth materials and their
consequential effects on total magnet costs. Technical
teams are constantly at work to innovate new technologies
and optimize compositions to mitigate the
impact of these price fluctuations. The goal is to ensure
that designers attain maximum performance
from the MQ1 magnet within a specified budget,
thereby creating a harmonious balance between cost
and efficiency.
Figure 1 illustrates the magnetic properties that MQ1
magnets can achieve at room temperature.
Magnequench created cost-optimized MQ1 magnet
grades that replace higher-priced light rare earth
(LRE) elements such as Nd/NdPr with lower- and stable-priced
LREs such as Ce/La - without a significant
sacrifice in magnetics in both room and high-temperature
thermal properties. Table 1 presents the representative
MQ1 magnet grades. For an example, replacing
almost 60% of total rare earth (TRE) by Ce/La results
in only 18% reduction in magnet Br.
AUTOMOTIVE ENGINEERING
MAGNEQUENCH
Automotive Engineering - October 2023

Table of Contents for the Digital Edition of Automotive Engineering - October 2023
