A kind of preparation method of sleeper spring bar

Abstract

The invention discloses a method for preparing a sleeper spring bar, and relates to the technical field of metal functional material preparation. The mass percentage of sleeper elastic components is: carbon C: 0.56-0.60%; silicon Si: 1.8-2.0%; manganese Mn: 0.80-1.2%; vanadium V: 0.15-0.2%; copper Cu: <0.10%; Aluminum Al: <0.1%; Sulfur S: <0.015%; Phosphorus P: <0.015%; the balance is iron Fe, the oxygen content of impurity elements is O<12ppm; the nitrogen content is N<15ppm; The slag is smelted, then hot forged and hot rolled to make spring steel billets. The spring steel billet is used as the raw material, and the sleeper spring bar is formed after intermediate frequency induction heating, put into the gas co-infiltration furnace, and the gas nitrogen N, carbon C, oxygen O co-infiltration treatment is carried out under the condition of 480-520 °C. A 3-5 micron thick compound layer and a 0.1-0.2 mm thick co-infiltration layer are obtained on the surface; zinc-aluminum coating treatment is performed on the sleeper springs after gas co-infiltration, and baked at 300-350°C after coating Dry for 0.5-1 hour, and control the coating thickness at 3-5 microns.

Description

technical field [0001] The invention relates to the technical field of preparation of metal functional materials. Background technique [0002] The railway sleeper spring is an important part of the railway fastener system, which is used to buckle on the rail and play the role of fixing the rail and reducing vibration and noise during the operation of the train. Sleeper clips are generally made of spring steel. After hot forming, quenching, medium temperature tempering and surface anti-corrosion are sequentially performed. Not only high fatigue resistance is required, but also excellent environmental corrosion resistance is required. However, in the actual production process, oil cooling is used for quenching. When tempering, the oil on the surface of the clip will burn and produce a lot of oily smoke, which will pollute the environment. Before surface anticorrosion treatment, surface cleaning and activation treatment are also required, which will generate waste liquid, etc...

AI Technical Summary

Problems solved by technology

However, in the actual production process, oil cooling is used for quenching. When tempering, the oil on the surface of the spring will burn and produce a lot of oily smoke, which will pollute the environment.

Before surface anti-corrosion treatment, surface cleaning and activation treatment are required, which will generate waste liquid, etc., and will also pollute the environment

At present, the main anti-corrosion method of sleeper elastic is powder zinc-nickel alloy + coating composite treatment. Powder metal infiltration not only has high cost, but also produces dust pollution.

In addition, according to the fatigue test standard TB / T2329-2002 for railway sleeper spring bars, the fatigue life of the spring bars should not be less than 5 million times, and the service life generally needs to be replaced within 5-8 years. The short service life greatly increases maintenance cost

Images