Assessment of mechanical behavior of PLA composites reinforced with Mg micro-particles through depth-sensing indentations analysis

This work deals with the mechanical characterization by depth-sensing indentation (DSI) of PLLA and PLDA composites reinforced with micro-particles of Mg (up to 15 wt%), which is a challenging task since the indented volume must provide information of the bulk composite, i.e. contain enough reinforc...

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Detalles Bibliográficos
Autores: Cifuentes, Sandra C., Frutos, E., Benavente, Rosario, Lorenzo, V., González-Carrasco, José Luis
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2017
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/143619
Acceso en línea:http://hdl.handle.net/10261/143619
Access Level:acceso abierto
Palabra clave:Biodegradable composites
Magnesium
Indentation tests
PLA
Mechanical properties
Descripción
Sumario:This work deals with the mechanical characterization by depth-sensing indentation (DSI) of PLLA and PLDA composites reinforced with micro-particles of Mg (up to 15 wt%), which is a challenging task since the indented volume must provide information of the bulk composite, i.e. contain enough reinforcement particles. The composites were fabricated by combining hot extrusion and compression moulding. Physico-chemical characterization by TGA and DSC indicates that Mg anticipates the thermal degradation of the polymers but does not compromise their stability during processing. Especial emphasis is devoted to determine the effect of strain rate and Mg content on mechanical behavior, thus important information about the visco-elastic behavior and time-dependent response of the composites is obtained. Relevant for the intended application is that Mg addition increases the elastic modulus and hardness of the polymeric matrices and induces a higher resistance to flow. The elastic modulus obtained by DSI experiments shows good agreement with that obtained by uniaxial compression tests. The results indicate that DSI experiments are a reliable method to calculate the modulus of polymeric composites reinforced with micro-particles. Taking into consideration the mechanical properties results, PLA/Mg composite could be used as substitute for biodegradable monolithic polymeric implants already in the market for orthopedics (freeform meshes, mini plates, screws, pins, …), craniomaxillofacial, or spine.