The bonding process in CoCrMo alloy: Fracture toughness in cobalt boride coatings

Campos-Silva I., Bravo-Barcenas D., Cimenoglu H., Figueroa-Lopez U., Flores-Jimenez M., Meydanoglu O.

SURFACE & COATINGS TECHNOLOGY, vol.260, pp.362-368, 2014 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 260
  • Publication Date: 2014
  • Doi Number: 10.1016/j.surfcoat.2014.07.092
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.362-368
  • Istanbul Technical University Affiliated: Yes


New fracture toughness (K-C) data for cobalt boride (CoB and CO2B) coatings were obtained using the Vickers depth-sensing microindentation technique. The coatings were developed on the surface of a CoCrMo alloy using the powder-pack bonding process at temperatures between 1223 and 1273 K using various exposure times for each temperature. The mechanical characterization of the boride coatings was divided into two procedures: first, Vickers indentations were conducted at constant distances from the surface using loads ranging from 15 to 450 mN. For the entire set of experimental conditions, the behavior of the indentation load as a function of the diagonal length (d(m)) was examined on the CoB and CO2B coatings. Second, the crack lengths emanated on the corners of the indentations marks (with applied loads above 250 mN) were measured on both coatings using a scanning electron microscope (SEM).