Enhancement of ductility, weakening of anisotropy behavior and local recrystallization in cold-rolled Ti-6Al-4V alloy strips by high-density electropulsing treatment

Abstract

The effect of high-density electropulsing treatment (EPT) on the microstructure, mechanical properties and fracture behavior of cold-rolled Ti-6Al-4V alloy strip was investigated. The results indicated that EPT accelerated the local recrystallization process tremendously in predeformed titanium alloy. The EPT-induced microstructural change resulted in remarkably increasing elongation to failure while remained tensile strength unchanged. In addition, anisotropy behavior of mechanical property is weakened dramatically. A mechanism for rapid local recrystallization in low temperature during EPT was proposed based on the reduction of nucleation thermodynamic barrier and enhancement of atomic diffusion. Uneven fractures of different direction specimens with quasi-cleavage fracture mode were gradually evolved into uniform ductile fracture mode with transgranular dimples under EPT.

Application of High-Density Electropulsing to Improve the Performance of Metallic Materials: Mechanisms, Microstructure and Properties

“…Under high density pulse current, the differences of mechanical properties almost diminished at a maximum current density of 5.4 × 10 3 A·mm −2 [ 62 ]. Similar results were found in the Ti-6Al-4V alloy and showed that EPT weakened the anisotropy behaviour of materials during plastic deformation, which may be attracted to the formation of non-directional fine equiaxed grains; the selective effect of current also supplies the directional energy input for grains’ evolution to relieve mechanical properties’ anisotropy [ 101 ].…”

“… The average maximum temperature of different metals and alloys with different peak current densities [ 24 , 30 , 52 , 53 , 59 , 63 , 67 , 78 , 82 , 85 , 98 , 101 , 112 , 114 , 123 , 125 , 131 ]. …”

RETRACTED ARTICLE: Effect of coupling asynchronous acoustoelectric effects on the corrosion behavior, microhardness and biocompatibility of biomedical titanium alloy strips

“…Recently, a novel style of energy input assisted processing technology to process the materials aiming to improve the microstructure and toughness has emerged, that is high-energy electro-pulse treatment (EPT). Electro-plasticity, electric field, and electromagnetic field can be applied concurrently within a short time and lower temperature in this process with ultra-high efficiency and low-cost [8][9][10]. Gromov et al [11] studied the structure, phase composition and dislocation substructure of steel subjected to EPT and found the fatigue durability increases within short time treatment.…”

Mechanical properties and tensile fracture of Ti–Al–V alloy strip under electropulsing-induced phase change

“…Moreover, Jiang et al 15 accelerated the solid solution process of beta-Mg17Al12 into the alpha matrix with the help of EPT even in a very short time of several seconds. Our previous experiments [16][17][18][19][20][21][22][23] also successfully applied the EPT in processing predeformed titanium alloys lowering the processing temperature and persisting time with improving microstructure in recovery and recrystallization process, thus improving the mechanical properties of titanium alloy strips and obtained FGM in a single long strip material.…”