Superplastic 5083 aluminum alloy sheet for high speed train

Lightweight is the inevitable trend of rail transit development, and aluminum alloy has light weight, high strength, strong corrosion resistance and good processing formability

Superplastic 5083 aluminum alloy sheet for high speed train

It is the preferred material for lightweight rail transit. AA5083 aluminum alloy belongs to Al Mg antirust aluminum alloy with good mechanical properties. Superplastic 5083 aluminum alloy sheet for high speed train produced by Chalco aluminum can produce various parts on high-speed rail, which can meet the strength requirements and reduce the manufacturing cost at the same time. Superplastic 5083 aluminum alloy sheet for high speed train can not only realize the forming of complex shape parts, but also meet the requirements of service strength and cost. However, the forming ability of aluminum alloy at room temperature is low, and it is difficult to form products with complex shapes, and there are some problems such as large springback, wrinkling, cracking and so on. Superplastic forming, as an advantageous process, can solve the problems of poor formability, easy cracking and springback defects of aluminum alloy at room temperature. Traditional superplastic forming requires materials to have small grain size and low strain rate when forming pipe shape. It has the defects of long production cycle and low production efficiency, which is difficult to meet the trend of fast-paced production at this stage.

The emergence of rapid superplastic forming technology, which combines the advantages of hot stamping technology and traditional superplastic forming technology, can solve the problem of traditional superplasticity

Forming problems. The rapid superplastic forming technology of side wall outer plate of prismatic skin of 250 km · h locomotive head of "Fuxing" standard EMU is studied. Superplastic 5083 aluminum alloy sheet for high speed train can not only meet the complex shape requirements of aluminum alloy parts, but also shorten the forming time and provide material basic parameters and process guidance for later process production design.

The rapid superplastic forming test was carried out on the outer plate of the side wall of the prismatic skin of the 250 km · h front of the standard EMU of "Fuxing" high speed railway. The size of the part is 6987 mm × 380 mm × 85 mm, the shape is a complex spatial curved surface, and there are sharp edges with fillet radius R ≤ 4 mm. Uniaxial tensile test is carried out on instron3342r high temperature tensile machine. The industrial AA5083 (o state) with thickness of 4 mm is selected. The optimal superplastic forming range of the material is determined through high temperature tensile test. In fact, superplastic 5083 aluminum alloy sheet for high speed train has better application prospects in the forming field of complex parts because its formability is better than that of industrial AA5083 sheet. However, considering the actual industrial production situation in China, it is very important to study the Superplasticity of industrial AA5083.

1) The commercial AA5083 aluminum alloy shows superplasticity under certain conditions. Temperature and strain rate have a significant effect on the Superplasticity of AA5083 aluminum alloy. At 500 ℃, 0.001 s-1, the elongation of AA5083 aluminum alloy reaches the maximum, and the elongation is 236.3%.

(2) according to the research results of the basic test, the high-speed rail head cover with complex spatial curved surface and sharp edges can be successfully developed by using the rapid superplastic forming process, and it can meet the performance requirements of rail transit.

(3) the rapid superplastic forming technology, which combines the advantages of hot drawing technology and traditional superplastic forming technology, can not only realize the forming of complex shape parts, but also shorten the production cycle and reduce the manufacturing cost.