在对半成品TC17钛合金整体叶盘进行表面腐蚀检查时,发现有的表面存在“亮条”的现象.通过显微组织观察、成分分析、硬度和力学性能测试等手段对“亮条”产生的原因及其对产品力学性能的影响进行了研究.由于TC17钛合金铸锭头部容易产生Cr偏析,从而形成Cr元素富集区,这些区域的相变点温度比基体低25～30℃,在热加工过程中形成了β斑点.这些β斑点即是“亮条”产生的原因.由于整体叶盘表面的β斑点较小,对室温拉伸性能和低周疲劳性能影响不大,仍满足使用要求.%The bright strips were found on the surface of TC17 titanium blisk during the corrosion detecting. The formation of the bright strips and its effect on the properties of the alloy were investigated by microstructure analysis, components analysis, microhardness and tensile tests. The results show that the element of Cr is easy to aggregate in the head of the ingot which results in the Cr - rich segregation. The beta transformation temperature of the Cr - rich segregation is lower than that of the matrix with 25 - 30 °C , thus the beta flecks are easy formed during the hot working. The beta flecks appear as the bright strips in the macrostructure. Due to the small size of the beta flecks, they have few effects on the tensile properties and low -cycle fatigue life of TC17 alloy. And all of the properties can meet the technical requirements in the present work.
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