Surface Modification of the EBM Ti-6Al-4V Alloy by Pulsed Ion Beam

Abstract

The effect of surface modification of Ti-6Al-4V samples manufactured by electron beam melting (EBM) using a pulsed carbon ion beam is studied in the present work. Based on the results of XRD, SEM, and TEM analysis, patterns of changes in the microstructure and phase composition of the EBM Ti-6Al-4V alloy, depending on the number of pulses of pulsed ion beam exposure, are revealed. It was found that gradient microstructure is formed as a result of pulsed ion beam irradiation of the EBM Ti-6Al-4V samples. The microstructure of the surface layer up to 300 nm thick is represented by the (α + α”) phase. At depths of 0.3 μm, the microstructure is mixed and contains alpha-phase plates and needle-shaped martensite. The mechanical properties were investigated using methods of uniaxial tensile tests, micro- and nanohardness measurements, and tribological tests. It was shown that surface modification by a pulsed ion beam at an energy density of 1.92 J/cm2 and five pulses leads to an increase in the micro- and nanohardness of the surface layers, a decrease in the wear rate, and a slight rise in the plasticity of EBM Ti-6Al-4V alloy.

Micromechanical Characterization of Additively Manufactured Ti-6Al-4V Parts Produced by Electron Beam Melting

“…49 For example, surface treatment techniques such as pulsed ion beam modifications can result in the formation of twinned martensite a¢¢ in EBM-produced Ti-6Al-4V. 50 Ti-6Al-4V produced by SLM also exhibits twins generated by the shear-induced transformation of the b phase. 51 Figure 6c shows a high-resolution transmission electron microscope (HRTEM) image of the crystalline structure in another TEM foil.…”

Изменение Ударной Вязкости Титановых Сплавов Вт8 И Вт14 После Поперечно-Винтовой Прокатки И Контролируемого Охлаждения

“…1 Власов И.В., 1 Гоморова Ю.Ф., 2 Яковлев А.В., 1 Найденкин Е.В. 1 Институт физики прочности и материаловедения СО РАН, Томск 2 Национальный исследовательский Томский политехнический университет, Томск Титановые деформируемые сплавы характеризуются высокими механическими свойствами, коррозионной стойкостью и низкой плотность, что позволяет изготавливать из них лёгкие и прочные изделия. Эти сплав хорошо свариваются и широко применяются для изготовления деталей ответственного назначения.…”

“…Дополнительным видом упрочнения может быть модификация поверхности [2], изменение химического состава сплава [3] или деформационное воздействие [4]. В этой связи применение поперечно-винтовой прокатки (ПВП) позволяет проводить контролируемое, при необходимости многоступенчатое, деформационное упрочнение [5].…”

Predicting the Strength of EBAM 3D Printed Ti-6Al-4V from Processing Conditions

“…Wire-fed EBAM processes have the advantage of high production speeds in addition to the ease of feedstock storage, availability and handling compared to powder-based AM. Importantly, wire-fed AM also originates from a feedstock less susceptible to contamination [2][3][4][5][6][7][8]. Finally, the shape and length scale of the feedstock-mm sized diameter wire as opposed to µm sized spherical metal particles [1,3,9,10]-help to improve the density of EBAM prints and diminishes the risk for porosity and inclusions.…”

“…Importantly, wire-fed AM also originates from a feedstock less susceptible to contamination [2][3][4][5][6][7][8]. Finally, the shape and length scale of the feedstock-mm sized diameter wire as opposed to µm sized spherical metal particles [1,3,9,10]-help to improve the density of EBAM prints and diminishes the risk for porosity and inclusions. However, as with all AM processes, there are issues of residual stresses, occasional internal voids as well as significant material property anisotropy.…”