1. Test materials
The research object selected in this experiment is ZG35CrMo steel for mechanical bearing pedestal, and its size is recorded. The size of bearing pedestal is 2360mm × 1640mm × 1280mm, the wall thickness of bearing pedestal is 52 ~ 256mm. In addition, the chemical composition of mechanical bearing pedestal should be studied, mainly by means of spectroxepos X-ray spectrometer. The results are as follows: the content of C is 0.32 ~ 0.40, the content of Si is 0.17 ~ 0.37, the content of Mn is 0.40 ~ 0.70, the content of Cr is 0.8 ~ 1.10, the content of Mo is 0.15 ~ 0.25, and the content of S, P, Ni and Cu is less than 0.5, in which the content of S is ≤ 0.035, P content ≤ 0.035, Ni content ≤ 0.30, Cu content ≤ 0.30.
2. Casting process parameters
In order to improve the performance of mechanical bearing pedestal to a certain extent, its process parameters must be studied during casting. Generally, the casting process parameters are studied with the help of gravity gating system. The specific casting process parameters are as follows: when the pouring temperature is controlled at 1460 ℃, 1480 ℃, 1500 ℃, 1520 ℃, 1530 ℃, 1540 ℃ and 1560 ℃, The pouring time in this temperature range is 90s, while the situation of 1530 ℃ is more complex. It is necessary to study the performance of mechanical bearing pedestal at the same temperature and different pouring time, and control the time within 45s, 60s, 75s, 105s and 120s.
3. Experimental method
For the impact test of the sample, jb30a impact testing machine shall be used to implement the specific working steps. The notch standard of the impact sample is V-notch sample, and the fracture shall be scanned by electron microscope after the test. Generally, jsm6510 scanning electron microscope (SEM) shall be selected for observation). The basic size of the sample shall also be strictly consistent, and its size shall be 50mm × 10mm. During the experiment, the specific parameters shall be controlled as 400R / min speed, 100N working pressure and 30min wear time, and the specific test shall be carried out in an appropriate temperature environment.