Study of the interface between adhered sheet metaland tool steel subjected to adhesive wear
(English)Manuscript (preprint) (Other academic)
Many products used every day have at least some parts manufactured by sheet metal forming.Sheet metal forming is well suited for mass production and many machines perform aforming step in a matter of seconds. A common and severe form of wear is called gallingand occurs as small amounts of the sheet material is transferred on to the tool.In the present study the interface between three different sheet materials and a powdermetallurgical tool steel was investigated based on morphology and chemical composition.The sheets used were a high strength carbon steel sheet CS, a stainless steel grade, SS andtitanium, Ti. The tool steel, Vancron 40, was selected based on previously shown resistanceto galling. The microstructure of the tool steel contains three major constituents, the steelmatrix, M6C carbides and MCN carbonitrides, each constituent with potentially differentadhesive properties.To investigate the interfaces between the tool and the adhered material cross sectionlamellas was cut using a focused ion beam and studied in a transmission electron microscope.The chemical compositions of the interfaces were also investigated using electronenergy-loss spectroscopyThe presence of an interlayer between the tool and the adhered material would be ofhigh interest as the adhesion in the interface governs galling. The study did not reveal anyinterlayer between tool constituents and adhered material, for Vancron 40 worn against CSand SS but for one combination. SS sheet showed a ≃ 10 nm morphological interlayeragainst a MCN carbonitride. The lubricant was removed from the contact area and no traceof it was left in the interface between tool and adhered sheet. This shows that adhesive wearoccurs during direct tool to sheet contact comparative to dry sliding in SOFS tests.
Galling, Interface, Micro structure
Research subject Materials Engineering
IdentifiersURN: urn:nbn:se:kau:diva-31842OAI: oai:DiVA.org:kau-31842DiVA: diva2:710019