IKA A 11.2 cutting blade, stainless steel, for A 11 basic, 0002905200

Kinetics of cutting and shear comminution

In materials science and biological sample preparation, tough, extremely elastic and fibrous matrices (such as thermoplastics, textiles, paper, cellulose or plant-based biomass) present a major physical challenge. Conventional impact mills fail in this context from a process engineering perspective, as elastic materials simply absorb the kinetic impact energy (damping effect) rather than fracturing brittle. The IKA A 11.2 cutting blade is geometrically engineered for high-precision shear comminution. Driven by the A 11 basic base unit at speeds of up to 28,000 revolutions per minute, the sharpened blades sever the macromolecular fibre structures by applying massive, localised shear stresses. This rotating, pulling cut continuously disaggregates the sample material and transforms it into a homogeneous, free-flowing analytical matrix.

Rheology and prevention of rotational blockages

A fundamental mechanical problem in the high-speed grinding of long, tear-resistant fibres is the so-called wrapping effect. Under conditions of severe flow turbulence, fibrous materials tend to wrap themselves around the mill’s rotating tool shaft. This leads to an exponential increase in torsional resistance, which can thermally overload or mechanically jam the drive motor in a fraction of a second. The A 11.2 cutting blade counteracts this rheological phenomenon thanks to its sharp cutting geometry. The blades systematically cut the fibres into short fragments long before static wrapping structures can form around the shaft, thereby maintaining the thermodynamic efficiency of the entire grinding process.

Material integrity and thermomechanical stability

To withstand the continuous mechanical abrasion caused by tough polymers or lignified plant fibres, the cutting blade is made from solid, highly wear-resistant stainless steel. The blades retain their microscopic sharpness even during extended grinding intervals under thermal stress. The corrosion-resistant, single-material design enables laboratories operating in accordance with strict GLP (Good Laboratory Practice) guidelines to carry out thorough chemical decontamination and residue-free thermal sterilisation in an autoclave, thereby preventing any analytical carry-over between batches.

Technical details

• Product type: Cutting blade / cutting tool (spare part)
• Processing principle: Cutting and shear comminution
• Physical scope of application: Tough, elastic and fibrous sample matrices
• Kinetic design: Designed for rotational speeds of up to 28,000 rpm
• Compatibility: Exclusively compatible with the IKA A 11 basic analytical mill
• Material: Solid, corrosion-resistant stainless steel with sharpened blades
• Assembly: Positive-lock, tool-free mounting on the drive shaft
• Hygiene: Fully thermally autoclavable and chemically sterilisable

Contents

• 1 x IKA A 11.2 cutting blade (stainless steel)

(Important note: The IKA A 11 basic analytical mill and the grinding chamber are not included in the scope of delivery!)

Custom requirements & accessories

The A 11.2 cutting blade is the most important wear part in terms of process technology for the fibrous cutting and comminution of materials. Processing extremely tough, sometimes abrasive plastics (such as fibre-reinforced polymers) inevitably leads to the gradual blunting of the cutting edges due to micro-collisions. A blunt blade tears the material rather than cutting it, which drastically increases the thermodynamic stress on the sample (frictional heat). To ensure gentle, thermally stable sample preparation, we recommend having replacement tools ready at an early stage should cutting performance begin to decline. Please contact our procurement service at any time for the strategic procurement of laboratory consumables.