Ti-22Al-25Nb合金板材的钎焊工艺

采用试验手段研究了Ti-22Al-25Nb合金板材的钎焊工艺. 结果表明,当钎焊温度为960 ℃时,Ti₂AlNb合金板材组织中短棒状O相组织发生少量溶解、块状O相组织的晶粒尺寸普遍增大,基体晶粒略粗化,但未出现相转变;随保温时间由15,30和60 min逐渐延长, Ti₂AlNb合金板材室温强度由1 257 MPa减少到1 000~1 100 MPa,但塑性不断提高,室温断后伸长率平均值由2.9%依次提高至3.4%,5.8%及5.0%. 确定出Ti₂AlNb合金板材的钎焊工艺参数为960 ℃/30 min/炉冷,此时相应接头抗剪强度较高,可达152 MPa.

Study on brazing process of Ti-22Al-25Nb alloy sheet

The brazing process of Ti-22Al-25Nb alloy sheet was studied. The influences on the microstructure and the tensile strength of the matrix from the brazing process were studied in this paper. The strength of the brazing joints was tested. A few of short rod O phases were dissolved and lots of O phases were grown up in the matrix during the brazing process as the brazing temperature being 960 ℃. The grain size of the matrix was increased without phase transition. With heat preservation time by 15, 30 and 60 min extended gradually, the room temperature strength of the matrix was decreased from 1 257 to 1 100 MPa and the average room temperature elongation was increased from 2.9% up to 3.4%, 5.8% and 5.0%. The optimized brazing technology parameters of Ti2AlNb alloy plate is 960 ℃/30 min/furnace cooling with the higher shear strength of the brazed joints as 152 MPa.