Internal Hole Burnishing Process
As the name suggests, burnishing is the process of compressing the surface roughness using rollers. This process results in mirror-like surfaces. Generally, it is applied to holes and shafts. When no heat treatment is applied, it produces excellent results on all types of metals (aluminum, cast iron, steel, stainless steel, bronze, etc.). It is performed after pre-processing operations such as turning and reaming. For cold-drawn or forged materials, chip removal is required before applying burnishing. This means that there must be surface roughness from the chip removal process for burnishing to take place. With internal hole tools, diameter adjustments can be made with a precision of 2.5 microns, or 0.0025 mm.
The most important aspect is that the process duration is very short, typically lasting only a few seconds.
Burnishing smooths the parts that have undergone pre-processing (turning, reaming, etc.), while simultaneously ensuring dimensional accuracy. For parts requiring precise surface finishes, burnishing offers an excellent alternative to honing, polishing, and grinding, providing a perfect surface in seconds.