Sliding contacts for the pharmaceutical industry: failure analysis and dry sliding tests for the replacement of hard Cr on AISI 316L steel. (January 2015) - Ceschini, L.
Abstract: Several alternatives were compared for the replacement of hard electroplated Cr coating to improve the tribological properties of the AISI 316L austenitic stainless steel for pharmaceutical packaging applications, including low temperature carburizing (LTC), thermal spray coatings (Al2 O3 -13TiO2, WC-17Co), substitution of the AISI 301 reference counterface with polymeric materials (PTFE, UHMWPE, PEEK). In dry sliding block on ring tests, the LTC AISI 316L cylinders lead to the lowest wear rates of the AISI301 sliders under low loads (up to 10 N). When considering the polymer vs. uncoated AISI 316L couple, PEEK and UHMWPE lead to lower friction and comparable wear rates with respect to the reference couple (AISI 301 vs. Hard Cr coated-AISI 316L) in the whole range of tested loads. Highlights: Failure analysis: identification of wear mechanisms (Hard-Cr coated AISI 316L vs. AISI 301). Lab slidingtests for ranking alternatives to Hard-Cr (2 solutions with different approaches). Solution (i): alternative coatings/treatments for AISI 316L. Solution (ii): polymers sliding against AISI 301. Best alternatives: (i) Low-temperature carburized AISI 316L or (ii) PEEK and UHMWPE.