Vacuum brazing of Ti3Al-based alloy to TiAI was firstly carried out by Ti-15Cu-15Ni （wt%） filler metal. A continuous Ti3Al band, Ti2Ni and Ti2Cu/Cu3Ti phases formed and the joint showed a shear strength of 53.8-112....Vacuum brazing of Ti3Al-based alloy to TiAI was firstly carried out by Ti-15Cu-15Ni （wt%） filler metal. A continuous Ti3Al band, Ti2Ni and Ti2Cu/Cu3Ti phases formed and the joint showed a shear strength of 53.8-112.4 MPa at room temperature. For the improvement of the joint strength, a new Ti--Zr--Cu--Ni--Fe filler alloy was designed, and its wettability on Ti3AI and TiA1 substrate was studied with the sessile drop method. After holding for 20 rain at 1010 ℃ the Ti--Zr--Cu--Ni--Fe filler showed a low contact angle of 20° and 21° on Ti3Al and TiAI substrate, respectively. The joint brazed with this novel filler mainly con- sisted of Ti-rich area, Ti3Al reaction layer and residual filler metal. With the increase of the brazing temperature, the amount of residual filler metal decreased and the TisAl reaction layer thickened. The Ti3Al/TiA1 joint brazed with Ti--Zr--Cu--Ni--Fe filler exhibited a lower hardness than that brazed with Ti--Cu--Ni filler. The corresponding joints brazed at 950 ℃ for 5 min presented the shear strength of 257.6± 33.6 MPa at room temperature and 304.8 ± 9.9 MPa at 600 ℃.展开更多
基金sponsored by the National Natural Science Foundation of China under Grant No. 51405456the Aeronautical Science Foundation of China under Grant Nos. 03H21009 and 99H21013
文摘Vacuum brazing of Ti3Al-based alloy to TiAI was firstly carried out by Ti-15Cu-15Ni （wt%） filler metal. A continuous Ti3Al band, Ti2Ni and Ti2Cu/Cu3Ti phases formed and the joint showed a shear strength of 53.8-112.4 MPa at room temperature. For the improvement of the joint strength, a new Ti--Zr--Cu--Ni--Fe filler alloy was designed, and its wettability on Ti3AI and TiA1 substrate was studied with the sessile drop method. After holding for 20 rain at 1010 ℃ the Ti--Zr--Cu--Ni--Fe filler showed a low contact angle of 20° and 21° on Ti3Al and TiAI substrate, respectively. The joint brazed with this novel filler mainly con- sisted of Ti-rich area, Ti3Al reaction layer and residual filler metal. With the increase of the brazing temperature, the amount of residual filler metal decreased and the TisAl reaction layer thickened. The Ti3Al/TiA1 joint brazed with Ti--Zr--Cu--Ni--Fe filler exhibited a lower hardness than that brazed with Ti--Cu--Ni filler. The corresponding joints brazed at 950 ℃ for 5 min presented the shear strength of 257.6± 33.6 MPa at room temperature and 304.8 ± 9.9 MPa at 600 ℃.
