FRACTURE TOUGHNESS OF HIGH-DENSITY SINTERED STEELS

J. Bris  F. Benítez  A. Mateo  J. Calero  M. Anglada  L. Llanes   

Anales de la Mecánica de la Fractura, nº 23 . 2006 . Pág. 397 -402
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Resumen: Yield stress, tensile strength and fracture toughness of a PM steel (Fe-4.0Ni-1.5Cu-0.5Mo-0.5C) have been studied as a function of sintered density in the high-level range, from 7.22 to 7.51 g/cm3. The material was processed by different routes combining both cold and warm compaction with single and double pressing-sintering sequences. Fracture toughness was tested by mode I crack opening in a three-point bending test in accordance with the standard procedure ASTM E-399. Validity of fracture toughness tests in these materials is discussed. A quantitative analysis of porosity was correlated with tensile and fracture parameters to assess the influence of pore morphology on mechanical behavior. Microstructural characterization reveals that pores tend to be bigger and more clustered at lower densities. All the mechanical properties increased with a reduction in porosity, being this conjugated performance a remarkable advantage over wrought steels. In spite of using three different lubricants in the processing routes involved, it is found that mechanical properties depend solely on the attained sintered density regardless the route followed to achieve it.

LocalizaciónAlbarracín

Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica, Universidad Politécnica de Cataluña
AMES S.A.,Sant Vincenç dels Horts
Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica, Universidad Politécnica de Cataluña
AMES S.A.,Sant Vincenç dels Horts
Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica, Universidad Politécnica de Cataluña
Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica, Universidad Politécnica de Cataluña