masterThesis
Desenvolvimento de material para ferramenta de corte cerâmica autolubrificada
Fecha
2018-08-10Registro en:
MEDEIROS, Diana Roberta da Silva. Desenvolvimento de material para ferramenta de corte cerâmica autolubrificada. 2018. 63f. Dissertação (Mestrado em Engenharia Mecânica) - Centro de Tecnologia, Universidade Federal do Rio Grande do Norte, Natal, 2018.
Autor
Medeiros, Diana Roberta da Silva
Resumen
Due to growing concern about the risks caused by the use of cutting fluid in the
machining process, substitution alternatives are sought, which is the case of the use
of self-lubricated cutting tools. However, the insertion of a lubricating material in the
cutting tool matrix modifies the physical-mechanical properties. Therefore, it is
necessary to know the properties and behavior of materials that will be used for this
purpose, once that they influence directly on the tool performance, its useful life, the
wear and the cost of the process. Given this, the work has been aimed to develop
and evaluate a self-lubricating cutting tool with alumina matrix (Al2O3) and
molybdenum disulfide (MoS2), Graphite and Barium Fluoride (BaF2) as solid
lubricants. The samples were developed from pure alumina and with compositions
containing 5, 10 and 15% of each solid lubricant in the matrix. The powders were
processed through the grinding and sintering via SPS. After, the compacted material
was characterized regarding microhardness, hardness, fracture toughness, and
roughness. The ability to lubricate was investigated in a pin-on-disc tribological test.
The fracture surfaces and wear were evaluated by scanning electron microscopy. As
results, it was observed that with the increase of the insertion of solid lubricant there
was a decrease in the values of microhardness, hardness, and fracture toughness.
The best tribological results were obtained for samples containing 15% of MoS2.