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Through utilizing the different photoluminescence properties of the Eu3+-activated NaLuF 4 nanoparticles and g-C 3 N 4 , the versatile applications of white light-emitting diode and ratiometric optical thermometer are realized. • NaLuF 4 : x Eu3+ nanoparticles can emit dazzling red emission with optimal doping content of 15 mol%. • NaLuF 4 : x Eu3+ nanoparticles have superior thermal stability and its IQE is 35.3%. • White-LED with high CRI (80.2), low CCT (5014 K) and proper LE (12.1 lm/W) is obtained. • The maximum S a and S r values of the designed composites are 0.0057 K−1 and 0.455% K−1, respectively. • The sensor sensitivities of the prepared composites can be modified by composition regulation. To overcome the existence challenge of the luminescent materials in versatile applications, NaLuF 4 : x Eu3+ nanopariticles and NaLuF 4 :0.15Eu3+@ y g-C 3 N 4 composites were designed. Under irradiation of 394 nm, dazzling red emissions with high color purity of 87.6% are observed in the NaLuF 4 : x Eu3+ nanoparticles and the optimizing content of the dopants is 15 mol%. The electric dipole-dipole interaction leads to the concentration dependent quenching effect. Through assessing the resistance performance of the resultant nanoparticles to the temperature, the studied samples are certified to show high thermal stability. Furthermore, the proper color rendering index (80.2), low correlated color temperature (5014 K) and suitable luminous efficiency (12.1 lm/W) of packaged white light-emitting diode reveal that the NaLuF 4 :0.15Eu3+ nanoparticles can be employed as the red component for white light-emitting diode. On account of the inconsistent photoluminescence performances of the NaLuF 4 :0.15Eu3+ nanoparticles and g-C 3 N 4 , the thermometric properties of the NaLuF 4 :0.15Eu3+@ y g-C 3 N 4 composites are explored. The maximum absolute and relative sensitivities of the designed composites are 0.0057 K−1 and 0.455% K−1, respectively, and their values are able to be manipulated via composition regulation. This work proposes a new sight into the exploitation of diverse photoluminescence behaviors of the g-C 3 N 4 and NaLuF 4 : x Eu3+ nanoparticles to realize versatile applications. [ABSTRACT FROM AUTHOR]

Novel tungsten-based W-K-Y alloys were sintered by spark plasma sintering (SPS) method using fine-grained yttrium doped tungsten-potassium (W-K) powder. The relative density, microstructure, hardness and the resistance to thermal shock damage of the sintered samples were characterized. With the enhanced Y doping, the grain size decreased and the hardness increased. Thermal shock test under 0.37 GW/m 2 heat load showed that low yttrium doping (0.05 wt%, 0.1 wt% and 0.5 wt%) in W-K-Y alloys can improve the resistance to thermal shock damage comparing with traditional commercial W-K, while high yttrium doping (1 wt%) easily leads to crack formation. This study will provide helpful information to optimize the preparation of tungsten-based plasma facing materials through composite tuning. [ABSTRACT FROM AUTHOR]

W K Mo Ti Y powder were mechanically alloyed (MA) and then consolidated through spark plasma sintering (SPS). Four different concentrations of molybdenum, i.e ., (0, 2, 5, 10) wt%, were applied to investigate the behavior of the alloys. The microstructure, Vickers micro-hardness and thermal shock behavior were analyzed. It is found that the molybdenum doping can mechanically alloy with tungsten and occupy tungsten lattice, which results in a correspondingly decrease of Vickers micro-hardness and thermal conductivity at the room temperature. Among the molybdenum doped samples, W K-2wt% Mo Ti Y alloy displays highly enhanced resistance against thermal shock. It is suggested that appropriate molybdenum doping in W K Mo Ti Y alloy is beneficial in consolidating and improving its thermal shock resistance. [ABSTRACT FROM AUTHOR]

Obtaining higher mechanical properties, particularly the coexistence of strength and ductility, is always an important issue for high-strength and high-ductile metastable β titanium alloy, such as Ti55531. Rare earth element doping to gain reticulate structure is a possible way to break the strength-ductility trade-off considering the excellent capability of yttrium in improving the properties of titanium alloys and limiting grain growth. In this study, a new strategy was devised for the preparation of Ti55531 alloys with a reticulate structure by introducing yttrium and a tailored spark plasma sintering (SPS) procedure. Compared to the homogeneous structure, the strength of the material with a reticulate structure is prominently improved at the little expense of loss in ductility. Furthermore, the addition of yttrium can significantly increase the precipitation of α phase by affecting the local element concentration. It is hoped that this study can provide important inspiration for improving the mechanical properties of powder metallurgy fabricated titanium alloys. • Titanium alloys with reticulate structure prepared by doping yttrium and SPS technology. • The Ti55531 alloy with reticulate structure has good strength-ductility matching. • Yttrium affects the microstructure evolution and crack propagation path of Ti55531 alloy. [ABSTRACT FROM AUTHOR]

The effect of potassium doping on the thermal shock behavior of tungsten is investigated in this paper. Traditional W–K samples with different potassium contents were tested by an electron beam at an absorbed power density of 0.37 GW/m 2 . It shows that the damage after thermal shock test is smaller with potassium content increasing, but the cracking threshold is not improved. It suggests that for traditional W–K sample the potassium bubbles do have some pinning effects on tungsten but not enough to prevent cracking in transient high heat load. The thermal shock behavior of spark plasma sintered W–K (SPS–WK) was comparably studied. In SPS–WK, potassium bubbles not only distribute along the grain boundaries but also retain inside the grains. Size of the potassium bubbles inside the grains is in the range of 20–100 nm. This microstructure leads to higher thermal shock resistance and no obvious damage occurred after transient high heat load at 0.37 GW/m 2 . This may provide some important information to improve thermal shock resistance for W–K PFM. [ABSTRACT FROM AUTHOR]