采用放电等离子体扩散焊接技术，以Ti/Ni/Ti箔为中间层，实现了Ti48Al2Cr2Nb合金之间的扩散连接. 研究了焊接时间和温度对接头显微组织的影响. 结果表明，950 ℃时，保温15 min，中间层和基体中元素互扩散有限；保温时间延长到30 min，中间层在接头处扩散均匀. 在相同保温时间30 min的条件下，900 ℃和950 ℃得到的接头界面存在分层，各个层的主要物相都是α2相，仅最内层存在α-Ti. 升高温度到1 000 ℃和1 050 ℃，接头界面分层消失，显微组织相似，都是由粗大的α2相和固溶了少量Ni原子，Nb原子，Cr原子的α2相组成. 放电等离子体烧结(SPS)对接头处的元素扩散有促进作用，尤其是Ni元素，使得接头内部没有TiNi和TiAlNi金属间化合物生成.
曹磊
,
张俊
,
谢跃煌
,
梁加淼
,
张德良
. 时间和温度对放电等离子体扩散焊接Ti48Al2Cr2Nb合金接头显微组织的影响[J]. 焊接学报, 2018
, 39(12)
: 119
-124
.
DOI: 10.12073/j.hjxb.2018390310
Ti-48Al-2Cr-2Nb (at.%) alloys were diffusively bonded using spark plasma sintering (SPS) with Ti/Ni/Ti foils as an interlayer. The results indicated that the mutual diffusion of the elements between the matrix alloy and the interlayer was limited at 950℃ with a holding time of 15 min. At the same temperature of 950℃, the diffusion of the elements was improved with increasing the holding time to 30 min. At the same holding time of 30 min, the joints showed the similar microstructures consisting of α2 phases as the main phases in each layer at the temperatures of 900℃ and 950℃, while the α-Ti only formed in the inner layer. With increasing the temperature to 1 000℃ and 1 050℃, the layers disappeared and the joints were characterized by coarsen α2 phases and the α2 phases with few solid solution Ni, Nb and Cr elements. SPS accelerated the diffusion of the elements in the joints, especially the Ni element, which inhibited the formation of TiNi and TiAlNi intermetallic compounds.
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