Influence of Heat Treatment on the Microstructure Evolution and Mechanical Properties of Graphene/Ti2AlNb Composites Synthesized via Spark Plasma Sintering

High-purity and bulk Ta4AlC3 ceramics were successfully fabricated by spark plasma sintering (SPS) and subsequent heat treatment, using the raw materials including TaC and Ta2AlC powders. These raw materials were first synthesized by self-propagation high temperature synthesis from elements tantalum, aluminium and carbon black powders, followed by pressure-less sintering. The as-fabricated bulk Ta4AlC3 was relatively stable when subjected to heat treatment at elevated temperature of 1500?C. Moreover, prolonging the heat treatment time resulted in bigger grain sizes and higher densities of the Ta4AlC3. The flexural strength and the fracture toughness of the Ta4AlC3 fabricated by SPS were found to be 411MPa and 7.11MPa?m1/2, respectively. After the heat treatment at 1500?C for 8 h, the flexural strength and the fracture toughness of the Ta4AlC3 could reach 709MPa and 9.23MPa?m1/2, respectively. The special structural characteristics of the ternary ceramics and the increase of density after the heat treatment are the main reasons for the variation in mechanical properties of ternary ceramics.

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202 Influences of alloy compositions and heat treatment conditions on Thermo^Mechanical Properties of Ti-Ni Shape Memory Alloy by Spark-Plasma Sintering

The Proceedings of the Materials and processing conference ◽

10.1299/jsmemp.2000.8.51 ◽

2000 ◽

Vol 2000.8 (0) ◽

pp. 51-52

Author(s):

Masakazu YOKOTA ◽

Hideki KYOGOKU ◽

Shinichiro KOMATSU ◽

Fusahito YOSHIDA

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Shape Memory Alloy ◽

Shape Memory ◽

Spark Plasma Sintering ◽

Treatment Conditions ◽

Plasma Sintering ◽

Spark Plasma

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Microstructure and Mechanical Properties of Ti-Nb Alloys Prepared by Mechanical Alloying and Spark Plasma Sintering

Journal of Materials Engineering and Performance ◽

10.1007/s11665-019-04417-0 ◽

2019 ◽

Vol 29 (3) ◽

pp. 1445-1452 ◽

Cited By ~ 2

Author(s):

Damian Kalita ◽

Łukasz Rogal ◽

Tomasz Czeppe ◽

Anna Wójcik ◽

Aleksandra Kolano-Burian ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Mechanical Alloying ◽

Spark Plasma Sintering ◽

Recoverable Strain ◽

Α Phase ◽

Plasma Sintering ◽

Nb Content ◽

Spark Plasma ◽

Sintered Alloys

Abstract The effect of Nb content on microstructure, mechanical properties and superelasticity was studied in Ti-Nb alloys fabricated by powder metallurgy route using mechanical alloying and spark plasma sintering. In the microstructure of the as-sintered materials, undissolved Nb particles as well as precipitations of α-phase at grain boundaries of β-grains were observed. In order to improve the homogeneity of the materials, additional heat treatment at 1250 °C for 24 h was performed. As a result, Nb particles were dissolved in the matrix and the amount of α-phase was reduced to 0.5 vol.%. Yield strength of the as-sintered alloys decreased with Nb content from 949 MPa for Ti-14Nb to 656 MPa for Ti-26Nb, as a result of the decreasing amount of α-phase precipitations. Heat treatment did not have a significant effect on mechanical properties of the alloys. A maximum recoverable strain of 3% was obtained for heat-treated Ti-14Nb, for which As and Af temperatures were − 12.4 and 2.2 °C, respectively.

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The Microstructure Evolution, Mechanical Properties and Densification Mechanism of TiAl-Based Alloys Prepared by Spark Plasma Sintering

Metals ◽

10.3390/met7060201 ◽

2017 ◽

Vol 7 (6) ◽

pp. 201 ◽

Cited By ~ 12

Author(s):

Dongjun Wang ◽

Hao Yuan ◽

Jianming Qiang

Keyword(s):

Mechanical Properties ◽

Spark Plasma Sintering ◽

Microstructure Evolution ◽

Densification Mechanism ◽

Plasma Sintering ◽

Spark Plasma

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Influence of Heat Treatment on Microstructure and Properties of NiTi46 Alloy Consolidated by Spark Plasma Sintering

Materials ◽

10.3390/ma12244075 ◽

2019 ◽

Vol 12 (24) ◽

pp. 4075 ◽

Cited By ~ 4

Author(s):

Pavel Salvetr ◽

Jaromír Dlouhý ◽

Andrea Školáková ◽

Filip Průša ◽

Pavel Novák ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Shape Memory ◽

Spark Plasma Sintering ◽

Scanning Calorimetry ◽

Slow Cooling ◽

Plasma Sintering ◽

High Temperature Synthesis ◽

Heat Treated ◽

Spark Plasma

Ni-Ti alloys are considered to be very important shape memory alloys with a wide application area including, e.g., biomaterials, actuators, couplings, and components in automotive, aerospace, and robotics industries. In this study, the NiTi46 (wt.%) alloy was prepared by a combination of self-propagating high-temperature synthesis, milling, and spark plasma sintering consolidation at three various temperatures. The compacted samples were subsequently heat-treated at temperatures between 400 °C and 900 °C with the following quenching in water or slow cooling in a closed furnace. The influence of the consolidation temperature and regime of heat treatment on the microstructure, mechanical properties, and temperatures of phase transformation was evaluated. The results demonstrate the brittle behaviour of the samples directly after spark plasma sintering at all temperatures by the compressive test and no transformation temperatures at differential scanning calorimetry curves. The biggest improvement of mechanical properties, which was mainly a ductility enhancement, was achieved by heat treatment at 700 °C. Slow cooling has to be recommended in order to obtain the shape memory properties.

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