Effects of Lanthanum and Zirconium on Cast Structure and Room Temperature Mechanical Properties of Mg-La-Zr Alloys

Nd, Y and Ca containing Mg-Zn-Zr alloys are produced by electromagnetic direct-chilling casting process, and extruded at a temperature of 643K with two extrusion ratios of 38:1 and 22:1, respectively. The grain size is markedly reduced from 80µm in as-cast alloy to 2~5µm in as-extruded alloy due to dynamic recrystallization, and lamellar eutectics at grain boundaries in as-cast alloy are broken up and fine precipitates in the matrix come forth during hot extrusions. Mechanical properties of the alloys are measured by tensile test from room temperature to 523K. Nd, Y and Ca are favorable to the strength of the hot-extruded alloy, especially the elevated-temperature strength, which is above 200MPa in ultimate tensile strength at 523K.

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Microstructure, Mechanical Properties, Creep and Corrosion Resistance of Mg-Gd-Y-Zr(-Ca) Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.546-549.101 ◽

2007 ◽

Vol 546-549 ◽

pp. 101-104 ◽

Cited By ~ 5

Author(s):

Shang Ming He ◽

Xiao Qin Zeng ◽

Li Ming Peng ◽

Xin Wu Guo ◽

Jian Wei Chang ◽

...

Keyword(s):

Mechanical Properties ◽

Corrosion Resistance ◽

Room Temperature ◽

Peak Hardness ◽

Slight Improvement ◽

Trace Concentration ◽

Obvious Effect ◽

X Ray ◽

Β Phase ◽

Zr Alloys

The microstructure, mechanical properties, creep and corrosion resistance of Mg-Gd-Y-Zr(-Ca) alloys were studied. Small additions of 0.4-0.6 wt% Ca to Mg-(9-10)Gd-3Y-0.4Zr(wt.%) alloys led to a slight improvement in creep resistance and a remarkable increase in corrosion resistance, but an obvious decrease in elongation to fracture. UTS and TYS of the Mg-Gd-Y-Zr(-Ca) alloys are obviously higher than those of WE54, especially in the temperature range from room temperature to 200 oC. TEM images and corresponding energy dispersive x-ray spectra showed that the Ca element primarily segregated to the grain boundaries and existed in the cuboid-shaped particles with a trace concentration, and the small addition of Ca had no obvious effect on the orientation, morphology, and distribution of β′ phase, which is responsible for the peak hardness in Mg-Gd-Y-Zr alloys.

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Mechanical Properties and Dislocation Structure of Single Crystal Cdte Deformed in Compression at 300°C

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010009292x ◽

1976 ◽

Vol 34 ◽

pp. 592-593

Author(s):

Ernest L. Hall ◽

J. B. Vander Sande

Keyword(s):

Mechanical Properties ◽

Single Crystal ◽

Dislocation Structure ◽

Room Temperature ◽

Elevated Temperatures ◽

Strain Curve ◽

Optical Devices ◽

Semiconductor Compound ◽

Wide Range ◽

Sample Orientation

The present paper describes research on the mechanical properties and related dislocation structure of CdTe, a II-VI semiconductor compound with a wide range of uses in electrical and optical devices. At room temperature CdTe exhibits little plasticity and at the same time relatively low strength and hardness. The mechanical behavior of CdTe was examined at elevated temperatures with the goal of understanding plastic flow in this material and eventually improving the room temperature properties. Several samples of single crystal CdTe of identical size and crystallographic orientation were deformed in compression at 300°C to various levels of total strain. A resolved shear stress vs. compressive glide strain curve (Figure la) was derived from the results of the tests and the knowledge of the sample orientation.

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Autonomous self-healing polyisoprene elastomers with high modulus and good toughness based on the synergy of dynamic ionic crosslinks and highly disordered crystals

Polymer Chemistry ◽

10.1039/d0py01034k ◽

2020 ◽

Vol 11 (41) ◽

pp. 6549-6558

Author(s):

Yohei Miwa ◽

Mayu Yamada ◽

Yu Shinke ◽

Shoichi Kutsumizu

Keyword(s):

Mechanical Properties ◽

Room Temperature ◽

Self Healing ◽

High Modulus ◽

Disordered Crystals ◽

Ionic Crosslinks

We designed a novel polyisoprene elastomer with high mechanical properties and autonomous self-healing capability at room temperature facilitated by the coexistence of dynamic ionic crosslinks and crystalline components that slowly reassembled.

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