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To obtain satisfactory joining between titanium alloys and stainless steel, it is of great significance to study the process of Ti-Fe eutectic reaction. The preliminary studies about the liquid forming, spreading and the structure of the contact reaction between pure Ti and pure Fe are carried out at 1 120℃for different holding times in high-frequency induction heated vacuum furnace. The results show that for Fe(particle-like)/Ti(plate-like) contact reaction couples, owing to Fe's higher density than titanium's, the Fe/Ti eutectic reaction develops in the thickness direction of plate-like Ti, named “deposition effect”. Then the eutectic reaction can be realized without the inter-diffusion between Ti and Fe atoms, so the formation rate of the liquid phase is very quick. For Ti (particle-like)/ Fe (plate-like) contact reaction couples, the eutectic reaction has a strong direction, i.e. the eutectic liquid is formed mostly at the Ti side, which leads to much dissolution of Ti particle and very little dissolution of the Fe base metal. It can be seen that the diffusion rate of Fe in Ti determines the whole process of the eutectic reaction, behaved as that the dissolution rate of Ti (particle-like)/ Fe (plate-like) is much lower than that of Fe(particle-like)/Ti(plate-like), and the dissolution rate of Ti obeys the square root law. Whatever means the Ti, Fe are assembled by, only dissolution process can be founded, the spread phenomena is unobvious, which is concerned with the formation of the intermetallic compounds and the “deposition effect” of Fe.
To obtain satisfactory joining between titanium alloys and stainless steel, it is of great significance to study the process of Ti-Fe eutectic reaction. The preliminary studies about the liquid forming, spreading and the structure of the contact reaction between pure Ti and pure Fe are The results show that for Fe (particle-like) / Ti (plate-like) contact reaction couples, owing to Fe's higher density than titanium's, the Fe / Ti eutectic reaction develops in the thickness direction of plate-like Ti, named “deposition effect ”. Then the eutectic reaction can be realized without the inter-diffusion between Ti and Fe atoms, so the formation rate of the liquid phase For Ti (particle-like) / Fe (plate-like) contact reaction couples, the eutectic reaction has a strong direction, ie the eutectic liquid is formed mostly at the Ti side, which leads to much dissolution of Ti particle and very little dissolution of the Fe base metal. It can be seen that the diffusion rate of Fe in Ti determines the whole process of the eutectic reaction, behaved as that the dissolution rate of Ti (particle-like) / Fe (plate-like ) is much lower than that of Fe (particle-like) / Ti (plate-like), and the dissolution rate of Ti obeys the square root law. Whatever means the Ti, Fe are assembled by, only dissolution process can be founded, the spread phenomena is unobvious, which is concerned with the formation of the intermetallic compounds and the “deposition effect” of Fe.