Development of low carbon alloy bucket teeth for excavators at China and abroad

In recent years, researchers at home and abroad have made great achievements in the research of bucket tooth alloy materials. It is found that the Ni Cr Mo low-carbon low-alloy martensitic steel developed by Amsco company has good strength and toughness, especially suitable for thin, long and sharp bucket teeth. Wen Xinlin et al. Have developed a kind of low carbon and low alloy wear-resistant material. The carbon content of the material is 0.20% – 0.27%, which can ensure the material has strong strength. In order to improve the comprehensive mechanical properties and processing performance of bucket tooth wear-resistant material, carbide was added to form elements Cr, Mn, Mo, which can significantly improve the hardness and wear resistance of the material. Ni can not only improve the toughness of the steel, but also improve the hardenability of the steel. After heat treatment, the carbide structure is uniform and fine, and the partition effect on the matrix is reduced. The uniform distribution of carbides can greatly improve the strength of the quenched material.

It is found that the service life of low carbon alloy steel is longer than that of high manganese steel. Yu Peng Chao of a metallurgical machinery factory developed a kind of low carbon wear-resistant alloy steel to replace the traditional zgmnl3 high manganese steel bucket teeth. Because of the nonlinear negative correlation between the carbon content and the plasticity and toughness of the material, the carbon content of the material can be reduced under the premise of meeting the requirements of application.

By controlling the alloy elements in the material, Cr, Mn, Si are the main elements, adding a small amount of Mo, V, Ti and proper amount of rare earth elements, the stability of cold austenite is improved, and the hardness and toughness of the material are improved finally.

Liu Xiaojun from the Department of materials engineering of a college analyzed the chemical composition, heat treatment process and material properties of low-carbon low-alloy steel, and obtained an ideal low-carbon low-alloy steel that can resist high stress and high impact load. The researchers controlled the carbon content of the steel to 025% and obtained a single lath like martensite structure.

Through the above analysis, it is found that according to the actual working conditions of bucket teeth at home and abroad, the material structure is improved by adding alloy elements and changing the heat treatment process, so as to improve the mechanical properties of bucket teeth.