Powder Metallurgy PTFE Components and PTFE-Metal Composites

Powder metallurgy is not only applicable to metals but can also be effectively used to produce PTFE (Teflon) components. PTFE is known for its low friction coefficient, excellent chemical resistance, and outstanding electrical insulation, which makes it widely used in bearings, gaskets, seals, and wear-resistant sliding elements. The process begins with precise dosing and pre-pressing of PTFE powders to form a green compact, followed by high-temperature sintering that rearranges molecular chains, eliminates interparticle voids, and enhances structural integrity. Unlike metals, PTFE does not truly melt during sintering; instead, its molecules undergo “solid-state fusion,” achieving densification while retaining the desired shape. Secondary machining after sintering can further improve dimensional accuracy. Components manufactured this way exhibit excellent wear resistance and chemical stability, capable of operating without additional lubrication, making them especially suitable for chemical pumps, automotive valves, and electronic devices. Through powder metallurgy, the traditional machining difficulties of PTFE can be overcome, improving production efficiency while reducing material waste, thus highlighting its value in high-performance non-metallic parts.

In earlier trials, we attempted pressing with fine PTFE powders, but limited flowability hindered production. The fibrous structures formed during granulation due to PTFE’s nature further worsened flowability, though adjustments eventually resolved this. We then advanced to blending PTFE with metals or ceramics to produce composite parts through sintering. These components are typically designed for applications requiring both PTFE’s low friction, high-temperature resistance, and chemical stability, combined with the high strength and wear resistance of metals or ceramics. The most common example is self-lubricating bearings and bushings. In the manufacturing process, bronze or stainless-steel powders are mixed with PTFE powders and sintered into composites at elevated temperatures. The metallic phase provides strength and thermal conductivity, while PTFE fills the voids between particles, forming a solid lubrication film. Bearings and bushings produced from these composites can operate stably for long periods without additional lubrication, and are widely applied in automotive, industrial machinery, and aerospace sectors.