PAI - Polyamide-imide

What Sets PAI Apart

PAI remains fully functional up to approximately 260°C without any significant loss of mechanical strength. At higher temperatures, the material is even stronger than many other plastics at room temperature. That combination, high strength that persists well into the high-temperature range, is what sets polyamide-imide apart from most other materials we can machine.

The material expands very little in response to temperature changes. For a part that must maintain tight tolerances while the ambient temperature fluctuates, this means that the dimensions remain accurate under varying conditions.

PAI is resistant to fuels, oils, and weak acids. However, the material is sensitive to strong alkalis, which are alkaline liquids, and prolonged exposure to high-temperature steam. Compared to PEI, another imide plastic that we machine at ANKRO, PAI is mechanically stronger and stiffer, but less easy to machine: PEI is ready for use immediately after machining, while PAI requires an additional step first.

PAI Plastic in Practice

PAI is used in applications where mechanical stress, heat, and tight tolerances come together. Examples:

• In the medical industry, we machine PAI for instrument components that are subjected to heavy loads yet must continue to function with precision, even after repeated use and sterilization. The material’s low creep ensures that a component retains the same tolerances after thousands of movements as it did on the first day.
• For mechanical and equipment engineering, ANKRO machines PAI for bearings and sliding components that must continue to function under high loads and at elevated temperatures, sometimes without external lubrication. Where an engineering plastic would already creep or deform under such loads, PAI retains its shape.
• In the analytical industry, we see demand for electrically insulating components that must maintain their insulating properties even at higher temperatures, for example in measuring equipment.

PAI in Series Production: Why That Is ANKRO’s Strength

With a single prototype, a slight loss of dimensional stability can sometimes be compensated for with post-processing. With a series of a hundred or a thousand units, that is not an option: every part must undergo the same conditioning cycle, the same cutting parameters, and the same inspection; otherwise, the deviation will quickly accumulate.

ANKRO has over 25 years of experience in scaling up from prototypes to series production while maintaining consistent quality across all parts. Maintaining that quality throughout an entire production run is woven into the process itself at ANKRO.