APPLICATION OF ALLOYS IN RAILWAY INDUSTRY

The applications of stainless steel in railway industry are as diverse as their applications in the transport domain. Different stainless steel grades provide the full choice for manufacturers. Whatever the rail transport in question, whether passenger, freight, metro or light rail transit system, VOJAY can offer a comprehensive range of stainless steels.

We offer the following steels and alloys for railway engineering:

Stainless steel

There is a growing trend by railway operators to favor austenitic stainless steel over carbon steels in the design and construction of rolling stock through the following benefits: high strength and reduced weight, high energy absorption at impact and greater corrosion and fire-resistance.

These qualities enable weight reduction through the creation of thinner sections, profiles and panels. For example temper rolled 301LN (1.4318) with its high strength and duplex stainless steels combine low nickel content with high mechanical strength making them an efficient alternative to standard strength grades. This offers cost saving benefits: thinner also means lighter, which for railcars, especially on commuter and metro routes, means significant energy savings over their entire life cycle.

VOJAY is able to provide outstanding high strength stainless steel grades in addition to many high-strength offerings for passenger rail car bodies in high-strength temper rolled AISI 301 (W.N.: 1.4310), AISI 301LN (W.N.: 1.4318), AISI 201 (W.N.: 1.4372), and etc.

The performance demands on freight vehicles are greater than ever: reduced maintenance, higher wear resistance and reduced tare weight are all key factors in their evolution. For example 1.4003, can be used for coal and ore freight wagons, metro and tram cars. It offers improved corrosion resistance when compared to carbon steels, often not requiring coatings to be applied. This can give substantial overall cost savings to the finished product.

Aluminium based alloys

The connection between the aluminum industry and railroads goes back a long way, in fact almost to the inception of the aluminum industry itself in 1888.

Aluminum alloys chosen for railcars are selected based on ease of fabrication, mechanical strength, weldability, and corrosion resistance. As a result, the workhorse materials normally used are the aluminum magnesium (5xxx) and and aluminum-magnesium-silicon (6xxx) alloy series. The 6xxx alloys are heat treatable and can offer higher strength, good corrosion performance, and good weldability.

The Aluminum Association (AA) manual on the repair of aluminum railcars indicates that the commonly used sheet or plate materials are alloys 5052, 5083, 5086, 5454 and 6061. The commonly used extrusion materials are 5083, 6061, and to a lesser degree, 7005. Newer alloys such as 5059, 5383, and 6082, have also been used for railcar applications. Welding is not an issue for most of the alloys just mentioned.

It is interesting to note that the advanced trains are still using these similar materials. For example, the Japanese Shinkansen uses 5083 alloy, and also some 7075 material, which is more frequently used as an aerospace material, while the German Transrapid uses 5005 sheet for panels and 6061, 6063, and 6005 for extrusions.

Some recent research for improved rail materials has been evaluating newer aluminum alloys containing scandium additions. Scandium provides the highest amount of strengthening per atom percent of any alloying element when added to aluminum. Small additions (0.1-0.2 wt%) have been shown to improve mechanical properties, refine the microstructures of wrought aluminum alloys, and improve weldability by reducing hot cracking in the weld region. Since all of these factors are relevant to rail applications of aluminum, a study was conducted to establish whether scandium-containing 5xxx, 6xxx, and 7xxx alloys could be used in conjunction with advanced welding technology such as friction stir welding, to improve the performance of aluminum alloys for rail applications.

Welding materials

In the course of construction, modernization or repair of rolling stock of the railway, as a rule, there is a need for welding materials. Depending on the construction material, VOJAY offers welding materials for carbon and stainless steels, nickel, aluminum and copper alloys.

Material selection in railway industry is not unique. The most of solutions lay in the sphere of science and technology, therefore require some kind of special knowledge in the relevant area.

Please contact our technical engineer for any help you may need in your specific application field.