Bucket tooth is a vulnerable part on the excavator bucket. When in use, the bucket tooth handle must have sufficient strength and toughness, and the tooth tip must have good wear resistance. The bucket teeth of the original excavator were basically the integral bucket teeth of single metal high manganese steel, and then gradually developed into combined bucket teeth and bimetallic composite bucket teeth.
The production methods of bimetallic composite bucket teeth mainly include surfacing bucket teeth, insert bucket teeth and electroslag casting bucket teeth. Bimetallic liquid composite casting bucket tooth is an integral bucket tooth obtained by pouring two different liquid metals in the same mold. The tooth tip part (lower part) is anti-wear high chromium white iron, and the tooth handle part (upper part) is high-strength and ductile low-alloy steel. The bonding quality of the transition zone of bucket teeth in bimetallic liquid composite casting directly affects the service life of bucket teeth. The production test of bucket teeth shows that the liquid iron level first poured into the tooth tip and the interval of double liquid pouring have a great influence on the bonding quality of the transition zone, but the influence law is difficult to be observed and understood with the naked eye. In view of the above situation, through the method of hydraulic simulation, this paper approximately describes the mixing state of bimetallic liquid in the transition zone under different conditions, and qualitatively explains its influence on the bonding quality of bucket teeth.
According to the literature and data on similarity theory, the bucket tooth model used in this experiment is exactly the same as the actual bucket tooth shape. Therefore, it can be considered that the two systems ensure dynamic similarity and motion similarity.
Because the temperature of the fluid used in the hydraulic simulation experiment is room temperature, it is difficult to simulate the different mixing states of the bimetallic transition zone in different intervals. In actual production, with the increase of pouring interval of bimetallic liquid, the temperature drop of molten iron increases, and the viscosity of molten iron increases accordingly, that is, the viscosity of molten iron is directly proportional to the interval. Therefore, the influence of the pouring interval of bimetallic liquid on the mixing state in the transition zone can be qualitatively described by using fluids with different viscosities.