Defects in aluminum alloy material
aluhm > 02-25-2018, 06:47 AM
1 size error due to the unreasonable mold design or manufacturing error, improper extrusion technology and die and extrusion of the cylinder, lubrication, such as unreasonable bring various points in the metal flow velocity difference is too large, resulting in a deformation of the profile, internal stress due to the large QianDongLi or lead to large amount of stretch of the profile size deviation.
A circular section of a circular section, such as the transverse section of a bar or tube, of varying diameters in each azimuth.
The bending length is not straight in the direction of length or width, showing the degree of the curve.
4 pull mark straight hook shape, visible to the naked eye to the local or full-length distribution of aluminum.
The cracks are usually straight in line, sometimes in the Y shape, often in the same direction as the drawing direction, but there are other directions, and the general opening is acute.
The surface of the corrosion material is partially overlapped, and there are obvious folds.
In the section of the layered material, there is an obvious separation of the metal structure. In severe cases, there are two or three layers, with visible inclusions between the layers.
8 distribution of bubble surface without rules is round, big and small convex hull, its outer edge is smooth, mostly take, also some not pluck up and shine after pickling flat surface, the layered shear section
9. The point on the surface of the profile is either partial or continuous, with the appearance of different densities, with a trailing or very small tumor, and the sensation of sharp prickles. Severe hemp spots similar to orange peel, larger and deeper than hemp.
10 After anodizing of black spot profile, there are approximately circular black and gray spots, which are different in size.
11 An expression of loose material that is not dense. After the slice is eroded by acid, it is expanded into many caves, according to its distribution can be divided into general loose and center loose.
12 The distribution of chemical compositions and non-metallic inclusions in the materials is not uniform. It can be divided into dendritic segregation, box segregation, point segregation and reverse segregation according to its manifestation.
13 shrinkage cavity residual in the central part of the transverse acid test film, showing irregular cavity or crack. Foreign impurities often remain in holes or cracks.