Aluminum tube cracks

During aluminum tube rolling, cracks are small ruptures that occur on the surface of the rolled aluminum tube. Mostly in a 45 degree angle or triangular shape along the rolling direction.

Rolling cracks are mainly caused by uneven deformation of metal.

During rolling, the interface between the front sliding zone and the rear sliding zone in the deformation zone is subjected to pressure in opposite directions. When the hole opening value is too large, the uneven deformation of the metal is large, the tension is also large, and the metal in the front sliding zone and the rear sliding zone is subjected to friction in opposite directions. This friction also acts on the interface of the front and rear sliding zones at the same time. When the tension on the interface is greater than the tensile strength of the metal, cracks will appear on the interface.

Rolling cracks mostly occur in hard alloys.

When the hole spacing is too small and the hole opening is too large, the uneven deformation of the metal will be large and the tendency to produce rolling cracks will also increase.

In addition, the extrusion temperature of the aluminum tube billet is too low, the annealing of the raw material is not good, the feed amount is too large, the rolling coefficient is too large, and there are relatively deep scratches on the surface of the tube billet, which will also cause cracks.

Improving the quality of aluminum billets will reduce cracks in aluminum tubes.

Optimizing the hole design quality, or increasing the hole gap and reducing the feed amount can effectively eliminate cracks in the aluminum tube.