aluminum products:Performance index and Test method

Performance index and Test method of aluminum products. 

1. The test for mechanical properties:

a: Tensile strength

Unit: MPA (Mpa) , unit of pressure, when stretching the specimen, Strength “N”in case of irrecoverable tensile deformation of the specimen, divided by the cross-sectional area of the specimen “Mm”, i.e. , n/mm (Newton Square mm) , 1n/mm = 1MPA

b: Yield strength

Unit: MPA (Mpa) , unit of pressure, when bending the specimen,

Strength “N”in case of irrecoverable bending deformation of the specimen, then divided by the cross-sectional area of the sample “Mm”, that is, n/mm (Newton Square mm) , 1n/mm = 1MPA

c: Earing rate

Unit: Percentage. After the cup test, uneven convex-concave and wavy protrusions appear on the rim of the Cup (see pic 1,pic2)

Measure the height of the highest part and the lowest part and convert it to scale. The greater the value, the greater the difference. The lower the earing rate is, the flatter the edge of the pressed cup mouth is, the lower the reject rate is, and the very low earing rate does not need to be cut. The higher the earing rate, the greater the anisotropy (anisotropy means that all or part of the chemical and physical properties of the material change with the change of the direction, showing different properties in different directions, resulting in the process of stamping, the deformation of each direction is very different)

2. The bending test for Color coated aluminum

Test method for flexural properties of coated materials. When the coating material is stressed beyond the bending or adhesion strength of the coating, it will cause cracking, paint stripping and leakage of the substrate. The test requires that the surface of the coating does not crack or paint off after the product is bent. Testing is mostly used for building materials products.

3. The testing of Dyne

The method of determining the Dyne value ：Draw a line on the surface of the material with a dyne pen. After 2-3 seconds, observe whether it shrinks and condenses into droplets.

If there is any shrinkage, change the number of a lower level of the pen to draw a straight line, until no shrinkage, no drops, to determine the surface tension value of the object, the surface dyne value of product is the level of the dyne pen.

The higher the dyne value, the cleaner the surface, the better the tension, and the better the adhesion of the coating on the surface. Surface contaminants such as grease, dust, and fingerprints can reduce the material’s dyne value