The Challenge

A manufacturer of high-speed electric motors (10,000+ RPM) for power tools and industrial equipment was experiencing premature carbon brush failure. The issues included:

• Excessive sparking at the commutator interface
• Accelerated commutator groove wear requiring frequent motor refurbishment
• Inconsistent brush density from poor copper powder compaction, leading to uneven current distribution

The Solution

LSBT recommended switching to CU-EP dendritic copper powder with tightly controlled apparent density (1.8-2.2 g/cm³). The dendritic morphology provides:

• Superior compaction — branched particle structure interlocks during pressing, yielding uniform green density
• Better carbon-copper bonding — high surface area enhances sintering and creates a more homogeneous composite
• Consistent electrical conductivity — uniform microstructure ensures even current distribution across the brush face
• Self-lubricating film formation — promotes a stable copper oxide film on the commutator surface

The Results

The reformulated carbon brush, using LSBT's CU-EP powder, doubled service life from 500 to over 1,000 operating hours under continuous high-speed operation. Sparking was virtually eliminated, and commutator maintenance intervals tripled.