Mechanical response and effects of β-to-α" phase transformation on the strengthening of Ti–10V–2Fe–3Al during one-dimensional shock loading

2013 ◽  
Vol 562 ◽  
pp. 137-143 ◽  
Author(s):  
Yu Ren ◽  
Fuchi Wang ◽  
Shuyou Wang ◽  
Chengwen Tan ◽  
Xiaodong Yu ◽  
...  
2018 ◽  
Vol 183 ◽  
pp. 02013 ◽  
Author(s):  
G. Whiteman ◽  
D.L. Higgins ◽  
B. Pang ◽  
J.C.F. Millett ◽  
Y-L. Chiu ◽  
...  

The microstructural and mechanical response of materials to shock loading is of the utmost importance in the development of constitutive models for high strain-rate applications. However, unlike a purely mechanical response, to ensure that the microstructure has been generated under conditions of pure one dimensional strain, the target assembly requires both a complex array of momentum traps to prevent lateral releases entering the specimen location from the edges and spall plates to prevent tensile interactions (spall) affecting the microstructure. In this paper, we examine these effects by performing microhardness profiles of shock loaded copper and tantalum samples. In general, variations in hardness both parallel and perpendicular to the shock direction were small indicating successful momentum trapping. Variations in hardness at different locations relative to the impact face are discussed in terms of the initial degree of cold work and the ability to generate and move dislocations in the samples.


2018 ◽  
Vol 183 ◽  
pp. 02010 ◽  
Author(s):  
Jeremy Millett ◽  
George. Gray ◽  
Glenn Whiteman ◽  
Saryu. Fensin ◽  
Gareth Owen

The behaviour of metals under mechanical loading, including shock loading conditions is strongly influenced by effects such as impurity levels, grain size, initial dislocation density and texture. The work discussed here is part of a wider study on the effects of orientation of aluminium single crystals to one dimensional shock loading, including the Hugoniot Elastic Limit and spall strength. In this work, specimens with three principle directions (<100>, <110> and <111>) parallel to the loading axis have been shock loaded and recovered under conditions of purely one-dimensional strain, with their post shock response monitored by quasi-static compression tests. Results show that the <100> crystal demonstrates a significant degree of post shock hardening, whilst the <111> crystal shows virtually none, and the <110> intermediate between the two. These results are consistent with the ordering of both the HELs and spall strengths observed in a previous paper, and have been explained in terms of the Schmidt factors.


2006 ◽  
Vol 100 (3) ◽  
pp. 033513 ◽  
Author(s):  
Y. J. E. Meziere ◽  
J. C. F. Millett ◽  
N. K. Bourne

Author(s):  
Syed Ejaz Hussain ◽  
Weiguo Wang ◽  
Xinfu Gu ◽  
Yunkai Cui ◽  
Ahua Du ◽  
...  

Metals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 163
Author(s):  
Shu Wang ◽  
Yilong Liang ◽  
Hao Sun ◽  
Xin Feng ◽  
Chaowen Huang

The main objective of the present study was to understand the oxygen ingress in titanium alloys at high temperatures. Investigations reveal that the oxygen diffusion layer (ODL) caused by oxygen ingress significantly affects the mechanical properties of titanium alloys. In the present study, the high-temperature oxygen ingress behavior of TC21 alloy with a lamellar microstructure was investigated. Microstructural characterizations were analyzed through optical microscopy (OM), scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), and transmission electron microscopy (TEM). Obtained results demonstrate that oxygen-induced phase transformation not only enhances the precipitation of secondary α-phase (αs) and forms more primary α phase (αp), but also promotes the recrystallization of the ODL. It was found that as the temperature of oxygen uptake increases, the thickness of the ODL initially increases and then decreases. The maximum depth of the ODL was obtained for the oxygen uptake temperature of 960 °C. In addition, a gradient microstructure (αp + β + βtrans)/(αp + βtrans)/(αp + β) was observed in the experiment. Meanwhile, it was also found that the hardness and dislocation density in the ODL is higher than that that of the matrix.


2017 ◽  
Vol 29 (7) ◽  
pp. 3246-3250 ◽  
Author(s):  
Tanghao Liu ◽  
Yingxia Zong ◽  
Yuanyuan Zhou ◽  
Mengjin Yang ◽  
Zhen Li ◽  
...  

2021 ◽  
pp. 107754632110458
Author(s):  
Hamze Mousavi ◽  
Moein Mirzaei ◽  
Samira Jalilvand

The present work investigates the vibrational properties of a DNA-like structure by means of a harmonic Hamiltonian and the Green’s function formalism. The DNA sequence is considered as a quasi one-dimensional system in which the mass-spring pairs are randomly distributed inside each crystalline unit. The sizes of the units inside the system are increased, in a step-by-step approach, so that the actual condition of the DNA could be modeled more accurately. The linear-elastic forces mimicking the bonds between the pairs are initially considered constant along the entire length of the system. In the next step, these forces are randomly shuffled so as to take into account the inherent randomness of the DNA. The results reveal that increasing the number of mass-spring pairs in the crystalline structure decreases the influence of randomness on the mechanical behavior of the structure. This also holds true for systems with larger crystalline units. The obtained results can be used to investigate the mechanical behavior of similar macro-systems.


Author(s):  
N.K Bourne ◽  
G.T Gray

Previous work on the shock loading of metals, has shown that one-dimensional strain histories may be only be approximated in a loaded sample if it is to be recovered at late times to examine microstructure. This proceeds through the use of a system of partial momentum traps and soft, shock-recovery techniques. However, limitations in the degree of uniaxial loading, and on the trapping of tensile pulses, have led to redesign of the target. In the current paper the technique is first assessed, and then modifications are explored to further refine it. Additionally it is illustrated how it may be applied to successfully recover targets of lower innate fracture toughness than has been previously documented. In the first part of the paper, the authors review work undergone to shock recover metals, and highlight associated constraints. In the latter part of the paper, a series of hydrocode simulations is presented to illustrate the design of an improved shock recovery technique that has now been adopted.


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