The Bending Behavior Investigation Of 6N01 Aluminum Profile For High-speed Train

Aluminum alloy has low density, moderate strength and higher corrosion resistance, etc. So it is very suit material to create the high-speed train and metro train. Bending is one of the most commonly used processes for large thin-walled aluminum extrusions. However, due to the production and application of aluminum alloy train body rather late in our country, the relate data is lack and mechanical properties is not universal. So it has great significance to study the mechanical properties and bending behavior of 6N01 aluminum profiles. First have the tensile, metallographic observation, SEM scanning test. Then execute the aluminum plates and profiles three-point bending test and finite element simulation. The results show that:6N01 aluminum profiles have inhomogeneity mechanical properties in different locations and different extrusion. That because it has different microstructure, which is mainly come from the extrusion, cooling and heat treatment; T4 heat treatment 6N01 aluminum alloy yield strength and tensile strength is more than 150MP and 186MPa, and minimum elongation is 23%. The inhomogeneity of T4 heat treatment 6N01 aluminum mainly in plastic deformation resistance and plastic deformation, and the impact on the ultimate bearing capacity is relatively small; T4 heat treatment 6N01 aluminum fracture has many dimples that are a typical microporous gathered fracture; T5 heat treatment 6N01 precipitation is a lot of granular Mg2Si and Al5FeSi. So its minimum yield strength and the tensile strength increased to 220 MPa and 282 MPa, the plastic decrease to 8.5%; T5 heat treatment 6N01 inhomogeneity still exists. Its fracture is a kind of intergranular fracture with a sugar-like microscopic morphology, the local has dimples; It is found that 6N01-T4 sheet has a good bending ability. When the thickness is less than 10mm, the minimum relative bend radius can reach 1; 6N01-T5 sheet’ bending ability is less than 6N01-T4. Its minimum relative bend radius is 2.8-2.9; it’s useful to simulate the bending process accurately by ANSYS/LSDYNA, and the minimum bend radius and bend angle are consistent with the actual experiments. Double chamber 6N01-T4 aluminum profiles have a good bending ability. Its major failure form is cross-section distortion as the main and the minimum bend radius decrease with thickness increasing; the bending ability of 6N01-T5 is decrease. Its major failure form is fracture, and the minimum bend radius increase with thickness decreasing; the finite element simulation can study three-point bending aluminum profiles with various factors, and find the optimal solution of these factors to provide guidance for the actual production.