Microstructural and Mechanical Properties of Titanium Matrix Composites Reinforced with Nano Carbon Materials via Powder Metallurgy Process

Powder metallurgy (P/M) titanium matrix composite (TMC) reinforced with multi-wall carbon nanotube (MWCNT) was prepared by spark plasma sintering (SPS) and hot extrusion process, where the powder surface was coated by un-bundled CNTs via wet process. The microstructure and mechanical properties of P/M pure titanium and reinforced with CNTs were evaluated. The distribution of CNTs and in-situ formed titanium carbide (TiC) compounds during sintering was investigated by optical and scanning electron microscopy (SEM) equipped with EDS analyser. The mechanical properties of TMC were significantly improved by adding a small amount of CNTs. For example, when employing the pure titanium composite powder coated with CNTs of 0.35 mass%, the increase of tensile strength and yield stress of the extruded TMC was 157 MPa and 169 MPa, respectively, compared to those of extruded titanium materials with no CNT additive. Fractured surfaces of specimens were analysed by SEM, and the uniform distribution of CNTs and TiC particles, being effective for the dispersion strengthening, at the surface of the TMC were obviously observed.

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CNTs/TiC Reinforced Titanium Matrix Nanocomposites via Powder Metallurgy and Its Microstructural and Mechanical Properties

Journal of Nanomaterials ◽

10.1155/2008/127538 ◽

2008 ◽

Vol 2008 ◽

pp. 1-4 ◽

Cited By ~ 23

Author(s):

Katsuyoshi Kondoh ◽

Thotsaphon Threrujirapapong ◽

Hisashi Imai ◽

Junko Umeda ◽

Bunshi Fugetsu

Keyword(s):

Mechanical Properties ◽

Powder Metallurgy ◽

Pure Titanium ◽

Multiwall Carbon Nanotubes ◽

Hot Extrusion ◽

Extrusion Process ◽

Dispersion Strengthening ◽

Titanium Matrix ◽

Wet Process ◽

Plasma Sintering

By using pure titanium powder coated with unbundled multiwall carbon nanotubes (MWCNTs) via wet process, powder metallurgy (P/M) titanium matrix composite (TMC) reinforced with the CNTs was prepared by spark plasma sintering (SPS) and subsequently hot extrusion process. The microstructure and mechanical properties of P/M pure titanium and reinforced with CNTs were evaluated. The distribution of CNTs and in situ formed titanium carbide (TiC) compounds during sintering was investigated by optical and scanning electron microscopy (SEM) equipped with EDS analyzer. The mechanical properties of TMC were significantly improved by the additive of CNTs. For example, when employing the pure titanium composite powder coated with CNTs of 0.35 mass%, the increase of tensile strength and yield stress of the extruded TMC was 157 MPa and 169 MPa, respectively, compared to those of extruded titanium materials with no CNT additive. Fractured surfaces of tensile specimens were analyzed by SEM, and the uniform distribution of CNTs and TiC particles, being effective for the dispersion strengthening, at the surface of the TMC were obviously observed.

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The Preparation and Mechanical Properties of a Pure Titanium-Based Matrix Composite Reinforced with Graphene Nanoplatelets

Science of Advanced Materials ◽

10.1166/sam.2020.3531 ◽

2020 ◽

Vol 12 (2) ◽

pp. 296-303

Author(s):

Zai-Yu Zhang ◽

Yi-Long Liang ◽

Hong-Chuan Cao ◽

Yong Zhu

Keyword(s):

Mechanical Properties ◽

Matrix Composite ◽

Testing Machine ◽

Pure Titanium ◽

Graphene Nanoplatelets ◽

Matrix Composites ◽

Dispersion Strengthening ◽

Titanium Matrix ◽

Vacuum Sintering ◽

Materials Used

A lightweight titanium matrix composite material was fabricated by vacuum sintering using semi-powder metallurgy. The graphene nanoplatelets (GNPs) were used as a reinforcement for the titanium matrix composites. Fabricating the composite materials used three steps: dispersion, formation, and sintering. In particular, GNPs were dispersed by ionic liquid through a centrifugal testing machine instead of ball milling in the process. The better pressure for composite forming was 600 MPa. At the same time, the better sintering temperature and holding time were 1200 °C and 3 h. The influences of the GNP addition on the density, microstructure, and microhardness of the Ti/GNP composites were investigated. For the mechanical properties of the composites, we focused on the tensile strength with different GNP contents. The Ti 0.075 wt% and Ti 0.15 wt% GNP composites exhibited yield strengths of 850 and 948 MPa, which demonstrated 66% and 85% increase compared to those of extruded titanium materials with no GNP additive (512 MPa yield strength). The main strengthening mechanisms of Ti/GNP composites are grain refinement strengthening, thermal mismatch strengthening, and dispersion strengthening.

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Influence of Carbon Reinforcements on the Mechanical Properties of Ti Composites via Powder Metallurgy and Hot Extrusion

Materials Science Forum ◽

10.4028/www.scientific.net/msf.750.40 ◽

2013 ◽

Vol 750 ◽

pp. 40-43 ◽

Cited By ~ 4

Author(s):

Shu Feng Li ◽

Bin Sun ◽

Katsuyoshi Kondoh ◽

Takanori Mimoto ◽

Hisashi Imai

Keyword(s):

Mechanical Properties ◽

Powder Metallurgy ◽

Carbon Nanofiber ◽

Hot Extrusion ◽

Strengthening Mechanism ◽

Matrix Composites ◽

Solid Solution Strengthening ◽

Plasma Sintering ◽

Spark Plasma ◽

Solution Strengthening

Ti metal matrix composites (Ti–MMCs) reinforced by vapor grown carbon nanofiber (VGCF) and graphite particle (Gr) were prepared via powder metallurgy and hot extrusion. Ti with 0~0.4wt% VGCF/Gr mixture powders were consolidated by using spark plasma sintering (SPS) at 800 °C. Hot extrusion was then performed at 1000 °C with an extrusion ratio of 37:1. Microstructures and mechanical properties of the as-extruded Ti composites were investigated. Tensile strength of Ti–VGCF/Gr composites was steadily augmented when additions of VGCF/Gr were increased from 0.1 to 0.4 wt%. YS and UTS were increased 40.2% and 11.4% for Ti–0.4wt%VGCF as compared to pure Ti, while those values were 30.5% and 2.1% for Ti–0.4wt%Gr. The strengthening mechanism including grain refinement, carbon solid solution strengthening and dispersion hardening of TiC/carbon was discussed in detail.

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Un-Bundled Carbon Nanotubes Reinforced Light Metal Composites via Powder Metallurgy Route

Materials Science Forum ◽

10.4028/www.scientific.net/msf.690.339 ◽

2011 ◽

Vol 690 ◽

pp. 339-342

Author(s):

Katsuyoshi Kondoh ◽

Thotsaphon Threrujirapapong ◽

Hiroyuki Fukuda ◽

Junko Umeda

Keyword(s):

Mechanical Properties ◽

Carbon Nanotubes ◽

Tensile Strength ◽

Powder Metallurgy ◽

Pure Titanium ◽

Hot Extrusion ◽

Light Metal ◽

Dispersion Strengthening ◽

Multi Wall Carbon Nanotubes

By using light metal (Mg, Al, Ti) powders coated with un-bundled multi-wall carbon nanotubes (MWCNTs) via wet process, powder metallurgy (P/M) light metal matrix composite reinforced with un-bundled nanotubes was prepared by spark plasma sintering (SPS) and subsequently hot extrusion process. The microstructure and mechanical properties of the composites were evaluated. In the case of pure titanium, the distribution of CNTs and in-situ formed titanium carbide (TiC) compounds during sintering was investigated by optical and scanning electron microscopy (SEM) equipped with EDS analyzer. The mechanical properties of TMC were significantly improved by the additive of CNTs. For example, when employing the pure titanium composite powder coated with CNTs of 0.35 mass%, the increase of tensile strength and yield stress of the extruded TMC was 157 MPa and 169 MPa, respectively, compared to those of extruded titanium materials with no CNT additive. Fractured surfaces of tensile specimens were analyzed by SEM, and the uniform distribution of CNTs and TiC particles, being effective for the dispersion strengthening, at the surface of the TMC were obviously observed. In the case of Mg-Al alloys, in-situ formation of Al2MgC2compounds at the interface between CNTs and Mg-matrix occurred and effective for the tensile transfer loading, and resulted in the increment of tensile strength of the composite material.

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