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采用电场辅助微塑性模锻成形技术成型了高强度、大硬度、低塑性的Ti6Al4V钛合金微齿轮.结果 表明,在电场作用下,圆柱形Ti6Al4V坯料在石墨模具中可以成型微齿轮.Ti6Al4V材料在加热速率为5℃/s时具有最佳的可成型性,较高的加热速率30和40℃/s可以有效地缩短材料预变形的时间.经电场辅助成型的样品均具有魏氏结构,但齿顶比齿心的组织更细小.加热速率为5和10℃/s的试样β相含量略高于原始坯料,但加热速率为20、30和40℃/s的试样没有显示出β相.此外,在电场作用下,所有成形样品的维氏硬度均有所增加.“,”A novel micro plastic forming technique was introduced to form micro-gears using the high strength,toughness,and hard-to-deform Ti6Al4V alloy materials.The results show that the Ti6Al4V alloy micro-gear can be achieved from a cylindrical Ti6Al4V billet with a set of graphite die under an electric field.The Ti6Al4V material exhibits the best formability when the heating rate is 5 ℃/s,while higher heating rate 30 and 40 ℃/s can effectively shorten the pre-heating time of materials for deformation.The microstructures of all the formed samples have the Widmanst～tten structure,but gear center is in contradiction to tooth top which exhibits a finer microstructure.The β phase content of specimens with the heating rates of 5 and 10 ℃/s is slightly higher than that of the original billet,but specimens with heating rates of 20,30,and 40 ℃/s show no β phase from XRD analysis.Moreover,Vickers hardness of all formed samples is higher than that of the original billet under an electric field,and it is independent on the heating rates.