Performance requirements for bucket teeth and hooks of excavators

In active service, the bucket teeth of excavator not only suffer drag damage, but also bear certain impact. Therefore, the surface layer of the idealized bucket tooth raw material of the excavator should have high strength and wear resistance, and the conventional material should have high compressive strength and ductility, which can not be exceeded by a single raw material. Nowadays, the key of bucket teeth in China is made of high manganese steel, which is also effectively made of carbon steel. It is generally believed that the surface layer of high manganese steel can reasonably cause cold work hardening layer only under the damage standard of high impact or strong chiseling. The main high-quality bucket hook factories of excavator bucket tooth manufacturers show high wear resistance, otherwise the wear-resistant bucket hook factories can not even keep up with the wear resistance of general steel. Figure 1 shows the cold work hardening curve of the bucket tooth tip position of 2m3 excavator and the bucket tooth tip position of bucket wheel excavator. It can be seen from the curve in the figure that the cold hardening strength of bucket teeth of bucket wheel excavator is not large, and the strength can only be hv315 No impact, medium level in-situ stress drags the wear-resistant material to damage, and its wear resistance is similar to that of general carbon structural steel. A layer of wear-resistant aluminum alloy is sprayed on the surface of cheap carbon steel or high alloy steel parts, which not only improves the wear resistance of the parts, but also maintains high strong ductility. This feature just takes into account the performance index requirements of the bucket teeth of the excavator, and the damage resistant spray welding reduces the provisions on conventional raw materials and the cost of raw materials. The standard of aluminum alloy series products with high manganese steel plate surface spray welding is to select spray welding aluminum alloy with high hardness and good wear resistance as far as possible if it can withstand the collision of raw materials in the application. In places where the impact is often obvious, it is possible to spray weld aluminum alloy with ferritic alloy steel. However, from the surface observation of high manganese steel bucket teeth and spray welded high chromium cast iron aluminum alloy bucket teeth, it is found that the pipe groove of high manganese steel damaged by wear-resistant materials is deeper than that of high chromium cast iron, which indicates that the wear resistance of high cobalt alloy pig iron is higher than that of high manganese steel. Therefore, it is generally strongly recommended to spray weld high chromium cast iron aluminum alloy or austenitic aluminum alloy pig iron on the surface of bucket teeth and bucket.