Leica SP2600 Ultramiller

The Leica SP2600 is a milling device which can be adapted to the Leica SM2500 sledge microtome. Instead of preparing thin sections for transmitted light microscopy, a polished surface is prepared for examination under reflected light.

The instrument is designed for industrial applications such as:

Metallography: milling of gold, silver, aluminium, copper without the need of embedding the specimen prior to the preparation
Food industry: milling of ice cream, cheese or other food using the liquid nitrogen device
Plastic industry: milling of plastics, gels, multi-layer foils or rubber using the liquid nitrogen device, etc.
Car industry: milling of car parts such as tanks, carpet embedded in resin, lacquer layers, etc.
Wood industry: milling of wood .

Please note: The instrument cannot be used to mill alloys containing iron, ceramics or glass.

Key Features

• Motorized milling unit (500 - 3000 rpm)
• Pre and finishing miller
• Variety of different diamond finishing millers for different applications
• Can be used together with the Liquid Nitrogen Device to mill soft specimens and elastomers.

Detailed Description

With its unique principle, the Leica SP2600 produces specimen surfaces for the light microscopic investigation which are compatible to polished surfaces. The advantage of the Leica SP2600 over grinding and polishing is, that even when milling materials of different hard and soft layers / particles are next to each other, there will be no rounded edges or the softer material smearing over the harder material.

Specimens can be directly clamped into the specimen holder without embedding them in plastic which is necessary for the grinding and polishing process.

When milling very soft material such as soft plastics or elastomers, the instrument can be equipped with a Liquid Nitrogen Device.

Principle:
Layer after layer of material, each layer of precisely the same thickness, is removed from a specimen block mounted onto a sledge travelling underneath a milling head consisting of a vertical, rotating spindle equipped with a diamond cutting tool on one and a balance weight on the other side.

The surface preparation procedure consists of two different steps: a preparation step carried out with a pre-miller and a finishing step during which a mirror-like surface with excellent edge definition is obtained.

Using the ultramilling technique makes it possible to track the area of interest in depth as the surface layer can be removed in micrometer steps.

Description of the pre-milling process:
The rotational speed of the spindle is adjustable from 500 to 3,000 rpm, the ideal speed in each case depending on the material being milled. Depending on the hardness of the material, material removal thickness can be adjusted starting from 1 µm per layer. To ensure high-quality final results the travelling speed of the sledge can also be adjusted according to the properties of each individual specimen being milled.

A diamond cutting tool with a triangular cutting geometry is used for the pre-milling step, where the block is trimmed down to the area of interest. Under the microscope, a pre-milled block surface will show a regular saw-tooth like pattern due to the triangular geometry of the pre-miller.

Description of the finishing step:
To obtain a smooth finished surface, the pre-miller is replaced by a finishing miller which removes the saw-tooth like pattern produced by the pre-miller leaving a perfectly even, mirror-like surface ready for investigation.