LSNT-300 Non-contact nondestructive testing system

Main specifications:

1. There are two modes: positioning scanning and automatic scanning;

2. Scanning area size up to 300 mm × 300 mm, positioning accuracy up to 5 μ m；

3. The detection line width or spacing can reach 0.5 mm, and the detection depth can reach 30 mm;

4. There are no restrictions on the size, number and times of applicable samples；

5. Use sample materials to contain metal samples.

Product features:

1. Automatic control interface;

2. High detection accuracy, simple operation method, and no damage to the sample to be tested; The sample surface can be scanned for defects;

3. The thickness, conductivity, magnetic permeability and other physical properties of conductor samples to be tested, such as conductor films and metal plates, shall be tested.

The surface defects of aluminum plate sample grooves with different depths (i.e. defects) are measured as shown in the figure below. Defects from left to right are: (a) surface grooves with a depth of 1mm; (b) Is a surface groove with a depth of 3mm; (c) Is an internal groove 4mm thick from the surface; (d) Is an internal groove 1 mm thick from the surface; (e) Is through hole groove; The width of each hole slot is 10mm. The conductivity of aluminum is 3.78X107(S.m-1), and the magnetic permeability is 1.2566X10-6(H.m-1).

Use the LabVIEW program to control the automatic scanning system to scan the sample surface according to the red snake path set in the figure, and set the step distance of Z-axis to 1.25 mm each time (specific value can be set according to the situation), and the scanning area to 70 × 118mm, the total number of measuring points is 56 × 94 There are 5264 points in total. Considering the influence of skin effect and better obtaining the surface morphology of the sample, test the detection conditions at different frequencies of 200, 500, 1500 and 5000 Hz respectively. First judge the defect position by high frequency, then adjust it to low frequency to further obtain the specific size and depth of the defect, and obtain the surface and near surface morphology of the sample by comparing the measurement results at different frequencies.