Why do you prefer rusty iron to stainless steel for train tracks? What will happen after using it?

Why do you prefer rusty iron to stainless steel for train tracks? What will happen after using it?

according to the statistics of relevant departments, nearly 3% of the steel products in the world are scrapped due to rust every year, and the quality and service life of those rusted steel will be greatly reduced. The harm of iron rust is so great, but why should the train track use rusty iron instead of stainless steel?

In fact, today's rails are made of alloy steel with more than 1% manganese and carbon added, which is also called high manganese steel. The strength and toughness of this kind of steel are far superior to other alloys dominated by iron, but due to the existence of iron, rust is inevitable. Just different from ordinary steel, the dense rust layer of high manganese steel only exists on the surface and will not be affected inside, just like a protective film, so even if it rusts, it will not affect the characteristics of the rail itself. However, since it will rust, it will cause loss to a greater or lesser extent. Why not use stainless steel directly to make rails at first?

This starts with the properties of stainless steel. Although there are various corrosion-resistant elements inside, stainless steel has low hardness, insufficient toughness and soft texture. If it is used as a rail, it can be easily deformed by a train with hundreds of tons. Moreover, chromium and nickel added in stainless steel are relatively scarce minerals, so the price of stainless steel made in this way is far higher than that of high manganese steel, and it is also very uneconomical to use it as railway tracks. So, for the rusty rails, is it necessary to do anti-rust treatment? In fact, large-scale rust prevention is unnecessary, because frequent friction between the wheel and the rail surface will make the contact surface difficult to rust, and once the rail bottom is rusted, the rust layer will protect it from further rust.

furthermore, the gravel of the track has good water permeability, which makes the track less susceptible to rain or moisture, and will soon become dry after the wind and rain. As for some key areas that need to be paid attention to for rust prevention, such as rail joints, splint bolt tips, rail tips and rail bending sections that are prone to friction, the common methods are cleaning and oiling. In addition, due to the humid environment and many harmful factors, the waste gas and waste water discharged by the train are not easy to spread in time, and the rails are more prone to rust, which also needs rust prevention treatment. The cathodic protection method of sacrificing anode in electrochemistry is used to protect the railway track. Specifically, every other sleeper is tied with a 3 cm by 3 cm chip, and the current is continuously applied to the rail surface through the chip, so that the rail becomes a cathode, so that the electron migration caused by metal corrosion is suppressed, and the corrosion is avoided or weakened. Simply put, the anode metal chip protects the rail from erosion with its own consumption.