RETRACTED-Effect of electropulsing treatment on the microstructure, texture, and mechanical properties of cold-rolled Ti
- PDF / 939,097 Bytes
- 13 Pages / 584.957 x 782.986 pts Page_size
- 59 Downloads / 244 Views
olin Song and Jie Kuang Advanced Materials Institute, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, PR China (Received 13 November 2013; accepted 17 June 2014)
Electropulsing treatment (EPT) provided a promising technology to improve the microstructure and plasticity of the cold-rolled Ti–6Al–4V noticeably while only affecting the strength mildly. Thus, titanium alloy of high plasticity and good comprehensive property can be obtained by this high efficient processing method. The research found that the tensile ductility could be improved largely with the increasing frequency. In the low frequency, the maximum ductility (32.5%) could be obtained at 293 Hz-EPT. Under high-frequency EPT, plasticity has a slight decrease but the tensile strength increases in the contrary. With the help of multi-characterization, abstracting phenomena are explained and therefore the conclusion has been drawn that the whole process of increasing frequency EPT can be divided roughly into two periods: (a) recrystallization period in the low frequency, at this period athermal effect of the EPT played a leading role and (b) phase change period in the high frequency, at this period the other important factor of the EPT thermal effect was predominant. As a comparison, furnace heat treatment is conducted to prove the preferential phase transition instead of complete recrystallization under the single heating effect. The mechanism of the results can be discussed by the competitive mechanism of recrystallization process and phase change in the EPT processing.
I. INTRODUCTION
Two-phase titanium alloys, such as Ti–6Al–4V, have been widely used as an excellent structural material in aeronautic, astronautic, automobile, chemical, and biomedical industries and thanks to its ideal properties like low density, high strength-density ratio, superior corrosion resistance, and fantastic biocompatibility.1–3 However, great resistance of deformation at an ambient condition inhibits the large-scale application especially for civilian use. For better formability, various traditional heating treatments (THTs) have been brought out in the materials post-processing treatments. Unfortunately, grain growth and severe oxidation layer on materials surface under the condition of high temperature and long-time furnace-heating, which deteriorates mechanical and inservice property.4 Electropulsing treatment (EPT), as a promising post-processing treatment technique, has been applied for improving the plasticity of metals and alloys5–8 and transforming the microstructure.9–12 Conrad et al.13,14 found that DC pulses facilitate the recovery and recrystallization in the annealing of cold-worked copper. a)
Address all correspondence to this author. e-mail: [email protected] DOI: 10.1557/jmr.2014.171 1500
J. Mater. Res., Vol. 29, No. 14, Jul 28, 2014
http://journals.cambridge.org
Downloaded: 12 Mar 2015
Gromov et al.15–17 studied dislocation substructure evolution on Al creep under weak electric potential and formation of surface gradient s
Data Loading...
