TRIBOLOGICAL PROPERTIES OF TIN COATINGS ELECTRODEPOSITED FROM PSA AND MSA BASED ELECTROLYTES

L. BENGOA; W. TUCKART; N. ZABALA; G. PRIETO; W. EGLI

JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE

SPRINGER

Lugar: Berlin; Año: 2015

1059-9495

A high efficiency methane sulfonic acid electrolyte used for tin electrodeposition was studied, and the properties of the resulting deposits were compared to those of tin coatings obtained from an industrial phenol sulfonic acid electrolyte. Cyclic voltammetry was used to study the effect of organic additives on the reduction process to define the composition of the electrolytic bath. Tin electrodeposition was carried out using a rotating cylinder electrode together with a concentric tin anode to achieve a uniform current distribution. Deposit morphology, crystal orientation and tribological behavior were characterized. Smooth, adherent and bright tin coatings were obtained from the methane sulfonic acid electrolyte, which differed in morphology and texture from tin electrodeposited from the industrial bath. Tribological tests showed that the two types of deposits have a similar coefficient of friction. However, tin coatings obtained from methane sulfonic electrolytes presented a lower wear resistance and underwent galling at lower loads. These results indicate that the evaluation of coating performance is a fundamental step in development of an electrolyte for tin deposition.