The influence of crystallographic texture and interstitial impurities on the mechanical behavior of zirconium

Abstract In this work, the hot forging behavior of a dual phase stainless steel in the temperature range of 850 – 1250 °C was investigated. The study revealed the occurrence of a significant cracking phenomenon for processing temperatures below 950 °C that was attributed to the combined effect of intermetallic precipitation and severe deformation. EBSD examination highlighted the occurrence of continuous dynamic recrystallization in both ferrite and austenite microstructures for processing temperatures above 1050 °C. Increasing the hot forging temperature to 1250 °C increased the low angle grain boundaries fraction and lowered the one of the high angle grain boundaries. This was accompanied by a gradual change in the crystallographic texture of the material. The mechanical behavior investigation showed that the steel plasticity, sharply dropped after forging at 850°, was gradually recovered after hot forging at temperatures above 1050°C. This was confirmed by nanoindentation measurements that revealed a remarkable increase of the hardness and young modulus of the steel after hot forging at 850°C and 950°C due to the dislocation nucleation and the s phase precipitation at g/δ interface. The enhancement of dislocation movement at the vicinity of the grain boundaries due to the absence of s phase as well as the dynamic recovery and recrystallization occurring in the temperature range of 1050°C - 1250 °C improved the global mechanical properties of the hot forged steel.

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Effect of single roll drive cross rolling on the microstructure, crystallographic texture, and mechanical behavior of Al–Zn–Mg–Cu alloy

Archives of Civil and Mechanical Engineering ◽

10.1007/s43452-021-00362-9 ◽

2022 ◽

Vol 22 (1) ◽

Author(s):

Amir Kazemi-Navaee ◽

Roohollah Jamaati ◽

Hamed Jamshidi Aval

Keyword(s):

Mechanical Behavior ◽

Crystallographic Texture ◽

Cross Rolling ◽

Cu Alloy ◽

Roll Drive

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Application of TEM to Deformation, Wear, and Fracture of Ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052377 ◽

1974 ◽

Vol 32 ◽

pp. 472-473

Author(s):

B. J. Hockey

Keyword(s):

Wear Resistance ◽

High Temperature ◽

Mechanical Behavior ◽

Brittle Materials ◽

High Temperature Strength ◽

Wide Range ◽

Corrosive Environments ◽

Further Development

Ceramics, such as Al2O3 and SiC have numerous current and potential uses in applications where high temperature strength, hardness, and wear resistance are required often in corrosive environments. These materials are, however, highly anisotropic and brittle, so that their mechanical behavior is often unpredictable. The further development of these materials will require a better understanding of the basic mechanisms controlling deformation, wear, and fracture.The purpose of this talk is to describe applications of TEM to the study of the deformation, wear, and fracture of Al2O3. Similar studies are currently being conducted on SiC and the techniques involved should be applicable to a wide range of hard, brittle materials.

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Phenomena Associated with Oxygen in Titanium

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061562 ◽

1967 ◽

Vol 25 ◽

pp. 310-311

Author(s):

E. U. Lee ◽

P. A. Garner ◽

J. S. Owens

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Electron Microscope ◽

Microstructural Changes ◽

Electrolytic Polishing ◽

Interstitial Impurities ◽

Thin Foils ◽

Transmission Electron ◽

Iodide Titanium ◽

Alpha Titanium

Evidence for ordering (1-6) of interstitial impurities (O and C) has been obtained in b.c.c. metals, such as niobium and tantalum. In this paper we report the atomic and microstructural changes in an oxygenated c.p.h. metal (alpha titanium) as observed by transmission electron microscopy and diffraction.Oxygen was introduced into zone-refined iodide titanium sheets of 0.005 in. thickness in an atmosphere of oxygen and argon at 650°C, homogenized at 800°C and furnace-cooled in argon. Subsequently, thin foils were prepared by electrolytic polishing and examined in a JEM-7 electron microscope, operated at 100 KV.

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