Effect of the Processing Parameters on the Porosity and Mechanical Behavior of Titanium Samples with Bimodal Microstructure Produced via Hot Pressing

Materials

Christopher Salvo¹  Sheila Lascano²  Mauricio Reyes-Valenzuela²  Sergio Sauceda²  Ricardo Chávez-Vásconez²  Ramalinga Viswanathan Mangalaraja³  Yadir Torres⁴  Cristina Arévalo⁴  Francisco José Gotor⁵ 

[1] Departamento de Ingeniería Mecánica, Facultad de Ingeniería, Universidad del Bío-Bío, Avda. Collao 1202, Casilla 5-C, Concepción 4081112, Chile;Departamento de Ingeniería Mecánica, Universidad Técnica Federico Santa María, Avenida Vicuña Mackenna 3939, Santiago 8940572, Chile;Departamento de Ingeniería de Materiales, Universidad de Concepción, Edmundo Larenas 270, Concepción 4070409, Chile;Departamento de Ingeniería y Ciencia de los Materiales y del Transporte, Escuela Poliécnica Superior, Calle Virgen de África 7, 41011 Seville, Spain;Instituto de Ciencia de Materiales de Sevilla (CSIC-US), Américo Vespucio 49, 41092 Sevilla, Spain;

关键词: porous titanium;    bimodal microstructure;    hot-pressing;    powder metallurgy;    mechanical milling;    mechanical behavior;   

DOI  :  10.3390/ma15010136

来源: DOAJ

【 摘 要 】

Commercially pure (c.p.) titanium grade IV with a bimodal microstructure is a promising material for biomedical implants. The influence of the processing parameters on the physical, microstructural, and mechanical properties was investigated. The bimodal microstructure was achieved from the blends of powder particles with different sizes, while the porous structure was obtained using the space-holder technique (50 vol.% of ammonium bicarbonate). Mechanically milled powders (10 and 20 h) were mixed in 50 wt.% or 75 wt.% with c.p. titanium. Four different mixtures of powders were precompacted via uniaxial cold pressing at 400 MPa. Then, the specimens were sintered at 750 °C via hot pressing in an argon gas atmosphere. The presence of a bimodal microstructure, comprised of small-grain regions separated by coarse-grain ones, was confirmed by optical and scanning electron microscopies. The samples with a bimodal microstructure exhibited an increase in the porosity compared with the commercially available pure Ti. In addition, the hardness was increased while the Young’s modulus was decreased in the specimens with 75 wt.% of the milled powders (20 h).

【 授权许可】

Unknown