The tunable negative thermal expansion covering a wide temperature range around room temperature in Sn, Mn co-substituted Mn3ZnN

A comprehensive study of the structure, phase composition, features of the surface topology, the magnetostrictive and thermal properties of the Tb0.8Sm0.2Fe2 compound are performed. The structural features were established at micro- and nanoscale levels, and information on the magnetic domains structure at room temperature was obtained. The results of x-ray diffraction studies in a wide temperature range of 90–760 K, including Curie temperature, are represented. Experimental data on thermal expansion and magnetostriction in magnetic fields up to 12 kOe were obtained and analyzed. Anomalies were found in the thermal expansion curves dl/l (T) and magnetostriction λ (T) at low temperatures. It is established that in compound under study the value of the magnetostrictive effect remains almost unchanged in a wide temperature range 100–300 K in fields up to 3.5 kOe.

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Strong negative thermal expansion in the hexagonal polymorph of ScF3

CrystEngComm ◽

10.1039/c8ce00257f ◽

2018 ◽

Vol 20 (20) ◽

pp. 2768-2771 ◽

Cited By ~ 2

Author(s):

Igor A. Kasatkin ◽

Larisa B. Gulina ◽

Natalia V. Platonova ◽

Valeri P. Tolstoy ◽

Igor V. Murin

Keyword(s):

Thermal Expansion ◽

Wide Temperature Range ◽

Negative Thermal Expansion ◽

Normal Pressure ◽

Temperature Range

A new hexagonal polymorph of scandium fluoride (ScF3) displays strong negative thermal expansion in a wide temperature range at normal pressure.

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Enlarging the Temperature Range for Maximum Wear Resistance of TiNi Alloy Using a NTE Phase

Materials Science Forum ◽

10.4028/www.scientific.net/msf.539-543.3261 ◽

2007 ◽

Vol 539-543 ◽

pp. 3261-3266 ◽

Cited By ~ 2

Author(s):

Iulian Radu ◽

Dong Yang Li

Keyword(s):

Wear Resistance ◽

Thermal Expansion ◽

Internal Stress ◽

Frictional Heating ◽

Negative Thermal Expansion ◽

High Wear Resistance ◽

Tini Alloy ◽

Wear Loss ◽

Second Phase ◽

Temperature Range

The near-equiatomic TiNi alloy has been demonstrated to possess high wear resistance, which largely benefits from its pseudoelasticity (PE). However, the PE occurs only in a small temperature range, which makes the wear resistance of this alloy unstable as temperature changes, caused by environmental instability or frictional heating. Therefore, enlarging the working temperature of PE could considerably improve this alloy as a novel wear-resistant material. One possible approach is to develop a self-built temperature-dependent internal stress field by taking the advance of the difference in thermal expansion between the pseudoelastic matrix and a reinforcing phase. Such a T-dependent internal stress could adjust the martensitic transformation temperature to respond changes in environmental temperature so that the temperature range of PE could be enlarged, thus leading to a wide temperature range in which the minimum wear loss is retained. Research was conducted to investigate effects of an added second phase having a negative thermal expansion (NTE) coefficient on the wear resistance of a near-equiatomic TiNi alloy. It was demonstrated that the temperature range of this modified material in which the wear loss dropped was enlarged. In addition, the wear resistance of such a TiNi-matrix composite was on one order of magnitude higher than that of unmodified TiNi alloy.

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Enhanced Negative Thermal Expansion Property Deduced by the Breaks of Superstructure

Science of Advanced Materials ◽

10.1166/sam.2021.3965 ◽

2021 ◽

Vol 13 (4) ◽

pp. 556-562

Author(s):

Niu Zhang ◽

Ming-Yi Wu ◽

Ya-Ming Liu ◽

Meng-Jie Yang ◽

Ming-Ju Chao ◽

...

Keyword(s):

Thermal Stability ◽

Thermal Expansion ◽

Wide Temperature Range ◽

Potential Application ◽

Negative Thermal Expansion ◽

Thermal Expansion Property ◽

Expansion Property ◽

Good Potential ◽

Nested Structure

The HfV2O7/HfMo2O8 composite were prepared in situ. The phase, structure and thermal expansion property were analyzed. The results indicate the composite consist of cubic HfV2O7 and hexagonal HfMo2O8. The two types of structures were coexisted and mixed uniformly, and interacted with each other. The mutual nested structure suppressed the formation of 3×3×3 superstructure in HfV2O7 (RT) introduced by the reaction in situ. The promoted coupled rotation of quasi-rigid polyhedron units could enhance the negative thermal expansion (NTE) property. The HfV2O7/HfMo2O8 composite exhibits excellent NTE property from 250 to 673 K (at least) with CTE -3.09 × 10-6 K-1. The good NTE property and thermal stability over a wide temperature range, especially near the RT range, bring a good potential application in designing zero thermal expansion materials.

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Isotropic Low Thermal Expansion over a Wide Temperature Range in Ti1–xZrxF3+x (0.1 ≤ x ≤ 0.5) Solid Solutions

Inorganic Chemistry ◽

10.1021/acs.inorgchem.8b02593 ◽

2018 ◽

Vol 57 (22) ◽

pp. 14396-14400 ◽

Cited By ~ 3

Author(s):

Cheng Yang ◽

Yugang Zhang ◽

Jianming Bai ◽

Peng Tong ◽

Jianchao Lin ◽

...

Keyword(s):

Thermal Expansion ◽

Solid Solutions ◽

Wide Temperature Range ◽

Temperature Range ◽

Low Thermal Expansion

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Phonon hydrodynamics and ultrahigh–room-temperature thermal conductivity in thin graphite

Science ◽

10.1126/science.aaz8043 ◽

2020 ◽

Vol 367 (6475) ◽

pp. 309-312 ◽

Cited By ~ 12

Author(s):

Yo Machida ◽

Nayuta Matsumoto ◽

Takayuki Isono ◽

Kamran Behnia

Keyword(s):

Thermal Conductivity ◽

Thermal Diffusivity ◽

Wide Temperature Range ◽

Room Temperature ◽

Phonon Dispersion ◽

High Conductivity ◽

Temperature Range ◽

A Value ◽

Out Of Plane ◽

Intimate Link

Allotropes of carbon, such as diamond and graphene, are among the best conductors of heat. We monitored the evolution of thermal conductivity in thin graphite as a function of temperature and thickness and found an intimate link between high conductivity, thickness, and phonon hydrodynamics. The room-temperature in-plane thermal conductivity of 8.5-micrometer-thick graphite was 4300 watts per meter-kelvin—a value well above that for diamond and slightly larger than in isotopically purified graphene. Warming enhances thermal diffusivity across a wide temperature range, supporting partially hydrodynamic phonon flow. The enhancement of thermal conductivity that we observed with decreasing thickness points to a correlation between the out-of-plane momentum of phonons and the fraction of momentum-relaxing collisions. We argue that this is due to the extreme phonon dispersion anisotropy in graphite.

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