Material guide
PK, polyketone
PK, polyketone, is a tough engineering plastic with good abrasion resistance and good sliding properties, plus unusually good resistance to hydrocarbons and fuels. A middle ground that takes a bit of the best from nylon and POM, without swelling with moisture the way nylon does.
What it is
PK, polyketone, is an engineering plastic that places itself between nylon and POM in properties. It is tough and impact resistant like nylon, but takes up considerably less moisture, so the dimensions hold better in a wet environment. At the same time it has good abrasion resistance and good sliding properties, much like POM. What really stands out is the resistance to hydrocarbons, fuels and many chemicals. PK is one of the newer and more unusual materials we carry, so get in touch early if you are planning a series.
Properties
Tough and impact resistant, even in the cold
Good abrasion resistance and good sliding properties
Takes up less moisture than nylon
Good resistance to hydrocarbons and fuels
Good dimensional stability in a damp environment
Common applications
PK is chosen for parts that have to wear, slide and at the same time stand up to fuels or hydrocarbons. Typical uses are sliding elements, gears, bearings and guides in environments where nylon would swell with moisture or where contact with fuel puts demands on chemical resistance. It is a good alternative when you want the toughness of nylon with the dimensional stability of POM.
Limitations
PK is not a high-temperature plastic, and it does not take hot environments the way PEEK or a fluoroplastic does. Against strong acids and bases the resistance is limited. The material is also fairly new and unusual in stock, so availability and lead time can vary more than for standard plastics. Gluing on the smooth surface is awkward, so count on mechanical fasteners.
Our PK grades take 100 °C in continuous service and 150 °C for short periods, go down to -30 °C and melt at 224 °C.
Grades and variants
We carry PK in the base version, typically in natural or black. Filled or modified grades can be ordered in on request.
Base grades
- PK base version, the tough, abrasion resistant base grade, typically in natural or black.
On request
- Filled and modified grades, can be ordered in on request when the series justifies it.
Machining
PK saws, mills, drills and turns without trouble. The surface is slippery and does not take adhesive, so count on screws, a press fit or another mechanical fastener.
Formats we can supply
We carry PK as sheet and round rod. You see formats and dimensions in the range. Want a piece cut to size? Put the measurements into VisualCutter and you see the price straight away.