Experimental Investigation on Tribological Property of Commercially Available Rosins for Violin Instrument at Room Temperature in Air

It is rosin that provides the physical basis of playing violin instruments, i.e. stick-slip between bow and string and hence the genesis of self-excited vibration of string. The tribological concept concerning rosin in playing violin instrument is briefly summarized in this study. Accordingly, the experimental investigation of rosin tribology on laboratory-based evaluation should include: (1) types of rosin, preparation and validity of samples for tribological tests, (2) choice of types of tribo-meters. Two kinds of commercially available rosins for cello and a kind of rosin for industry application were chosen in this study. Two kinds of liquid-solid processes, i.e. melting-solidification and solvent-evaporation, were utilized to fabricate rosin coating and rosin bulk material. The tribological properties of the rosin coatings and rosin bulk material were evaluated on a reciprocating tribo-meter with a ball-on-disk configuration. Findings indicated that the data of the tribological property for rosin coating by solvent-evaporation were good in term of repeatability. The tribogical properties of rosin were characterized as friction reduction, stick-slip, and dust wear. These were related to process of coating and bulk material, thickness of rosin coating, and counterpart material.