Ultrasonic Testing Method for Deformable Aluminum Alloy Products
Ultrasonic testing is an important means of ensuring the quality of deformable aluminum alloy products. Ultrasonic testing of metal materials can detect surface and internal defects, measure the thickness of metal materials, and determine the welding quality of various parts. Ultrasonic testing has the characteristics of being unaffected by the color of the test surface, being able to detect small and deep defects, wide test range, and being relatively portable.
GB 6519-86 ultrasonic testing method for deformable aluminum alloy products is a technical standard formulated for the inspection and acceptance of aluminum alloy products. This standard is divided into 5 chapters, namely product structure, degree of defects, test methods, acceptance criteria, test records and so on.
1、Product structure
The structure of an aluminum alloy product consists of an outer layer, an inner layer, a base layer, and an interlayer. In order to distinguish the aluminum alloy from the test surface, the surface is divided into outer side and surface according to the nature of the protrusion.
2、Defect Levels
Depending on the design surface requirements for aluminum alloy products, the defect levels are divided into four grades: A, B, C and D. Grade A is suitable for parts that require good appearance and strength; Grade B is suitable for parts that require moderate_strength; Grade C is suitable for parts that require higher strength; Grade D is suitable for the most stress insensitive parts.
3、Test methods
The test frequency, wave type, calibration of the equipment and other technical parameters of the ultrasonic test should meet the requirements of the technical standard of GB 6519-86. Insulated transducers should be used in the low-frequency corrosion test, and the scanning frequency should be below 4MHz. When the frequency is greater than 4MHz, the wavetype should be the longitudinal wave. The scanning mode of the test device should be a scanning of a surface.
4、Acceptance criteria
For defects with a size of 1mm or more detected by ultrasonic testing, a full-test acceptance criterion should be used with the following criteria: Grade A does not exceed 7, Grade B does not exceed 10, Grade C does not exceed 15, and Grade D does not exceed 18. For defects with a size of less than 1 mm, a partial test acceptance criterion should be used, which is that the total sum of defects detected by the total area of two thirds of the inspection area should not exceed the upper limit of the fault tolerance.
5、Test records
Aluminum alloy products should be tested, recorded and kept according to the technical requirements and operational procedures specified in GB 6519-86. The test records must include basic product information, test equipment parameters and defect information. The test records should also include the quality inspection personnels signature, date of signature and other related materials
In summary, ultrasonic testing can effectively ensure the quality of deformable aluminum alloy products by using the GB 6519-86 ultrasonic test method. This standard provides an effective test method for aluminum alloy products and provides effective means for ensuring product quality.
