Special electrode for overlaying and repairing high-chromium cast iron type high-speed rail substructure tamping pick

Abstract

Disclosed is a special electrode for overlaying and repairing a high-chromium cast iron type high-speed rail substructure tamping pick. In weight percent (wt%), chemical components of a coating of the special electrode include 3-5% of quartz, 7-9% of marble, 3-5% of fluorite, 4-6% of titanium white powder, 2-4% of chalk, 2-4% of silicon iron, 2-4% of high carbon ferromanganese, 1-3% of ferrotitanium, 38-45% of high-carbon ferrochromium, 20-25% of graphite and 2-6% of ferrotungsten, and a core wire is an H08A steel wire. By the aid of the electrode, the high-speed rail substructure tamping pick can be overlaid, repaired or remanufactured without preheating before welding and heat treatment after welding, deposited metal is high-chromium cast iron, an overlaid surface has high wear resistance, and the tamping pick is low in cost and extremely convenient to use on site. The surface hardness of the overlaid high-speed rail substructure tamping pick ranges from HRC (Rockwell hardness) 63 to HRC 67, and the service life of the repaired high-speed rail substructure tamping pick is three times of that of an integrally manufactured tamping pick.

Description

technical field [0001] The invention relates to a surfacing technology, in particular to a surfacing electrode. Background technique [0002] High-speed rail (high-speed railway) is the development trend of railway passenger transportation in the future. High-speed rail refers to railways with a maximum operating speed of more than 200km per hour, generally using EMUs. The emergence of high-speed rail has brought new challenges to the design, construction, maintenance and repair of traditional Chinese railway subgrades. The subgrade is the foundation for bearing the weight of the track structure and the train load, and is an important part of the railway line engineering. High-speed rail puts forward higher requirements for the smoothness and stability of the track. In addition to the basic performance of the general railway subgrade, the subgrade should also meet the performance requirements of the high-speed rail track for the subgrade. Therefore, as the foundation of th...

AI Technical Summary

Problems solved by technology

[0005] At present, some people have used chromium-molybdenum-tungsten-vanadium alloy as the wear-resistant layer material for tamping pick welding. Although the material can achieve high hardness, its wear resistance is obviously not enough when it interacts with high-hardness abrasive grains; In addition, there is also brazing of cemented carbide on the surface of the hammer to improve wear resistance, but due to the large difference in linear expansion coefficient between it and steel, it is easy to crack during the brazing process, and the strength and toughness cannot be reasonably matched. Carbide brittle fracture or falling off occurs during the working process, the effect has not been ideal, and the surfacing electrodes currently used are mainly imported