Spark plasma sintering and mechanical properties of zirconium micro-alloyed tungsten

Fabricating high performance tungsten alloys through zirconium micro-alloying and nano-sized yttria dispersion strengthening

“…First-principle calculations also indicate that the cohesion effect of transition metals, such as Zr, Hf, and Re, on GBs in W could significantly strengthen the GBs [11]. In one of our previous publications, W-0.2wt%Zr alloy showed considerable enhancement in the room-temperature fracture strength and toughness, because the Zr could capture oxygen in tungsten, form nano-scaled zirconia particles, and effectively alleviate the detrimental effect of oxygen [20]. Dispersing small amounts of oxide particles, such as La 2 O 3 , Y 2 O 3 , and HfO 2 into W and forming the so-called oxide-dispersion-strengthened W (ODS-W), can refine the grains and inhibit the movement of dislocations and GBs, and thus increase the high-temperature strength, recrystallization temperature, and creep resistance [21][22][23][24][25][26].…”

“…Tungsten carbide balls and mortars were used to minimize the possible impurity contamination. The chemical content of tungsten powder and ball-milling conditions were given elsewhere [20].…”

“…The temperature and pressure profile of the sintering program in this study was described elsewhere [20]. The as-prepared powders were loaded into a graphite mold at first and then under a uniaxial pressure of 47.7 MPa heated to 1800°C by a pulse current (1000-5000 A) and hold for 2 min.…”

Comparative Investigation of Tungsten Fibre Nets Reinforced Tungsten Composite Fabricated by Three Different Methods

“…The samples with the diameter of 20 mm were sintered by spark plasma sintering (SPS, FCT systeme GmbH, Rauenstein, Germany) according to the procedure as described in [26], which is shown in Figure 2a again for clarity, where the temperature was 1800 • C and the pressure was 47 MPa. The samples with the diameter of 60 mm were sintered in a hot-pressing vacuum furnace (HP, Shanghai Chen Xin Electric Furnace Co., Ltd., CXZT-60-23Y, Shanghai, China) with a heating or cooling rate of about 10 • C/min.…”

Chemically produced tungsten–praseodymium oxide composite sintered by spark plasma sintering

“…One such recent technological innovation is the use of spark plasma sintering (SPS), which is a pressure-assisted sintering that utilizes a large pulsed DC current (1000-5000 A) to heat the compacts and molds. SPS process provides fast heating rate (up to 1000°C/min) and short sintering time, and allows the consolidation of powder materials into dense fine-grained products at lower sintering temperature [23][24][25].…”