Reactive, nonreactive, and flash spark plasma sintering of Al₂O₃/SiC composites—A comparative study

Abstract

The influence of different SPS‐based methods, that is, conventional spark plasma sintering (SPS), flash SPS (FSPS), and reactive SPS (RSPS) on the properties of Al2O3/SiC composite was investigated. It was shown that the application of preliminary high energy ball milling of the powders significantly enhances the sinterability of the ceramics. It was also demonstrated that FSPS provides unique conditions for rapid, that is, less than a minute, consolidation of refractory ceramics. The Al2O3‐20 wt% SiC composite produced by FSPS possesses the highest relative density (~99%), fracture toughness (7.5 MPa m1/2), hardness (20.3 GPa) and wear resistance among all ceramics produced by other SPS‐based approaches with dwelling time 10 minutes. The RSPS ceramics hold the highest Young's modulus (390 GPa). Substitution of micron‐sized Al2O3 particles by nano alumina does not lead to measurable enhancement of the mechanical properties.

Comparison of Conventional and Flash Spark Plasma Sintering of Cu–Cr Pseudo-Alloys: Kinetics, Structure, Properties

“…In the FSPS scheme ( Figure S1b), the inner surface of the die was coated with electrical insulated material (i.e., hexagonal boron nitride) with a thickness of 0.2 ± 0.05 mm to prevent transmission of the DC pulses through the die and concentrating the entire current on the sample and graphite paper. The electrical insulation between the graphite die and the punches was verified, before and after each experiment by the multimeter (see [31] for more details). The temperature was increased manually at 100 K/min to 473 K, followed by rapid increase of the electrical current to the predetermined value in 5 s and kept for 10 s (see Figure S1b).…”

Comparison of Conventional and Flash Spark Plasma Sintering of Cu–Cr Pseudo-Alloys: Kinetics, Structure, Properties

“…In the FSPS scheme (Figure S1b), the inner surface of the die was coated with electrical insulated material (i.e., hexagonal boron nitride) with a thickness of 0.2 ± 0.05 mm to prevent transmission of the DC pulses through the die and concentrating the entire current on the sample and graphite paper. The www.videleaf.com electrical insulation between the graphite die and the punches was verified, before and after each experiment by the multimeter (see [31] for more details). The temperature was increased manually at 100 K/min to 473 K, followed by rapid increase of the electrical current to the predetermined value in 5 s and kept for 10 s (see Figure S1b).…”

A critical review on spark plasma sintering of copper and its alloys

“…Spark plasma sintering (SPS) is a novel consolidation technique that has been developed by combining the advantages of its predecessor methods such as vacuum sintering [1,2] and hot pressing [3,4]. This method takes advantage of preventing surface oxidation of materials at high temperatures [5], evaporation of impurities during the process due to low partial pressure [6], providing conditions for performing in situ synthesis that require vacuum [7], consolidation under inert or reactive atmospheres [8], and pressure-assisted densification [9]. Additionally, it includes the unique benefits that come from the direct application of electric current in sintering [10].…”