UHMW Precision Balls
Ultra-high-molecular-weight polyethylene (UHMWPE or UHMW), is a subset of the thermoplastic polyethylene. It has extremely long chains, with molecular weight numbering in the millions, which results in a very tough material, with the highest impact of any thermoplastic presently made. It is highly resistant to corrosive chemicals with exception of oxidizing acids; has extremely low moisture absorption and a very low coefficient of friction; is self-lubricating; and is highly resistant to abrasion, in some forms being 15 times more resistant to abrasion than carbon steel. Its coefficient of friction is significantly lower than that of nylon and acetal, and is comparable to polytetrafluoroethylene (PTFE), but UHMWPE has better abrasion resistance than PTFE. It is odorless, tasteless, and nontoxic.