In this study,the microstructure and mechanical properties of a multi-layered 316L-TiC composite material produced by selective laser melting(SLM)additive manufacturing process are investigated.Three different layers,...In this study,the microstructure and mechanical properties of a multi-layered 316L-TiC composite material produced by selective laser melting(SLM)additive manufacturing process are investigated.Three different layers,consisting of 316L stainless steel,316L-5 wt%TiC and 316L-10 wt%TiC,were additively manufactured.The microstructure of these layers was characterized by optical microscopy(OM)and scanning electron microscopy(SEM).X-ray diffraction(XRD)was used for phase analysis,and the mechanical properties were evaluated by tensile and nanoindentation tests.The microstructural observations show epitaxial grain growth within the composite layers,with the elongated grains growing predominantly in the build direction.XRD analysis confirms the successful incorporation of the TiC particles into the 316L matrix,with no unwanted phases present.Nanoindentation results indicate a significant increase in the hardness and modulus of elasticity of the composite layers compared to pure 316L stainless steel,suggesting improved mechanical properties.Tensile tests show remarkable strength values for the 316L-TiC composite samples,which can be attributed to the embedded TiC particles.These results highlight the potential of SLM in the production of multi-layer metal-ceramic composites for applications that require high strength and ductility of metallic components in addition to the exceptional hardness of the ceramic particles.展开更多
Metal-organic framework(MOF) thin films are multilayer materials ranging from nanometers to micrometers in thickness,physically or chemically adhesive to a(functionalized) substrate and,in an ideal case,exhibiting low...Metal-organic framework(MOF) thin films are multilayer materials ranging from nanometers to micrometers in thickness,physically or chemically adhesive to a(functionalized) substrate and,in an ideal case,exhibiting low roughness and high homogeneity.Various innovative approaches have been developed for MOF thin film fabrication.Among these advanced materials,surface-attached metal-organic frameworks(SURMOFs) are an important class of MOF films.SURMOFs,fabricated in a step-by-step liquid phase epitaxial(LPE) fashion by alternating deposition of metal and organic linker precursors on a functionalized substrate,for example,thiolate-based self-assembled monolayers(SAMs),have already exhibited their utility in both research and potential applications.SURMOFs combine surface science and the chemistry of MOFs,possessing the following unique advantages that cannot be accessed through other methods:(i) precisely controlling thickness,roughness and homogeneity as well as growth orientation,(ii) studying of MOF growth mechanism,(iii) modifying/tailoring MOFs' structures during the SURMOF growth and thus creating customizable properties,and(iv) existing in the form of thin film/membrane for direct applications,for example,as sensors.This review discusses the oriented and crystalline SURMOFs fabricated by LPE approach,covering their preparation,growth mechanism,and characterization methodology as well as applications based upon the most newly updated knowledge.展开更多
文摘In this study,the microstructure and mechanical properties of a multi-layered 316L-TiC composite material produced by selective laser melting(SLM)additive manufacturing process are investigated.Three different layers,consisting of 316L stainless steel,316L-5 wt%TiC and 316L-10 wt%TiC,were additively manufactured.The microstructure of these layers was characterized by optical microscopy(OM)and scanning electron microscopy(SEM).X-ray diffraction(XRD)was used for phase analysis,and the mechanical properties were evaluated by tensile and nanoindentation tests.The microstructural observations show epitaxial grain growth within the composite layers,with the elongated grains growing predominantly in the build direction.XRD analysis confirms the successful incorporation of the TiC particles into the 316L matrix,with no unwanted phases present.Nanoindentation results indicate a significant increase in the hardness and modulus of elasticity of the composite layers compared to pure 316L stainless steel,suggesting improved mechanical properties.Tensile tests show remarkable strength values for the 316L-TiC composite samples,which can be attributed to the embedded TiC particles.These results highlight the potential of SLM in the production of multi-layer metal-ceramic composites for applications that require high strength and ductility of metallic components in addition to the exceptional hardness of the ceramic particles.
基金the European Union for funding the research projects on MOF thin films (Priority Program 1362 of the DFG)SUR-MOFs(6th FP, NMP4-CT-2006-032109)
文摘Metal-organic framework(MOF) thin films are multilayer materials ranging from nanometers to micrometers in thickness,physically or chemically adhesive to a(functionalized) substrate and,in an ideal case,exhibiting low roughness and high homogeneity.Various innovative approaches have been developed for MOF thin film fabrication.Among these advanced materials,surface-attached metal-organic frameworks(SURMOFs) are an important class of MOF films.SURMOFs,fabricated in a step-by-step liquid phase epitaxial(LPE) fashion by alternating deposition of metal and organic linker precursors on a functionalized substrate,for example,thiolate-based self-assembled monolayers(SAMs),have already exhibited their utility in both research and potential applications.SURMOFs combine surface science and the chemistry of MOFs,possessing the following unique advantages that cannot be accessed through other methods:(i) precisely controlling thickness,roughness and homogeneity as well as growth orientation,(ii) studying of MOF growth mechanism,(iii) modifying/tailoring MOFs' structures during the SURMOF growth and thus creating customizable properties,and(iv) existing in the form of thin film/membrane for direct applications,for example,as sensors.This review discusses the oriented and crystalline SURMOFs fabricated by LPE approach,covering their preparation,growth mechanism,and characterization methodology as well as applications based upon the most newly updated knowledge.
