Figure 1 shows the mold filling and solidification of the investment casting process plan. It can be seen from Figure 1 that when the titanium liquid fills the mold, it first fills the investment casting at the left bottom, and then fills the right investment casting. The main reason is that the sectional area of the side ingate at the end of the rod is larger than the sectional area of the ingate at the anti-deformation rib. The titanium liquid first enters the mold cavity from the side ingate at the end, forming a gradient filling pattern of six investment castings. During solidification, the distribution of temperature field and the sequence of filling process are normal, and the temperature distribution is in a balanced solidification state. It can be seen from Figure 2 that after solidification, shrinkage defects are formed in the hot spot and the area where the shrinkage is not in place. The shrinkage defects are distributed at the large wall thickness ratio of the rod opening, and the other is φ At the hot spot at the junction of the 10 mm hole and the inner runner, the anti-deformation reinforcement and the inner runner form a hot spot, resulting in shrinkage defects. Due to the short process of titanium liquid, there is no shrinkage defect on the other side of the anti-deformation reinforcement.
Figure 3 shows the stress distribution of the investment casting process plan. From Figure 3, it can be seen that the stress concentration position is at the inner runner of the anti-deformation rib position. The stress value at the junction of the inner runner and the top bar is greater than 267 MPa, and the stress difference with the surrounding area is about 100 MPa, which is lower than that of the investment casting process plan, but φ The stress at the 10 mm end is relatively large, which is easy to produce deformation defects. The stress difference at the large wall thickness ratio of the rod opening is less than 100 MPa, and there is shrinkage defect here. During the use, there is a tendency for the interaction of stress and shrinkage defect to produce cracks.
