Moisture resistant microbial penetration tester

Applications include: rigid organic materials, paint adhesives, powder coatings, anodized materials, soft metals, plastics and glass, etc. It can also be used to test the quality of adhesives for the same material, protective coatings and the limiting properties of similar materials.

The instrument is composed of balance bar, fixed weight, adjusting weight and sample bearing disk.

Before the test, the height of the balance rod should be adjusted according to the thickness of the sample, so that the scraping head is installed in the middle of the balance rod and the sample is installed in the sample disk, so that the balance rod can be kept horizontal.

During the test, the fixed weight does not move and the moving regulating weight controls the weight pressed on the sample.

With the counterclockwise rotation of the loading disk, the scraping head left a curved notch on the sample surface.

1.1 Test Criteria

The scratch resistance tester meets the following standards:

LAS/NZS AS2924.2

lASTM C217

438.2 lBS EN

lBS EN 13310

lBS EN 14323

lDIN 68861-4

lDIN 53799

1.2 Test Principle

Place the sample in the groove of the thickness control device and adjust the position of the nut.

The sample is mounted on a rotatable circular platform and fixed with a presser and nut.

Install the scraping head into the groove corresponding to the center of the beam.

Rotate the balance bar so that the head of the scraping head is in contact with the sample.

Starting the instrument, the disk moves, and the scraping head leaves scratches on the surface of the sample.

1.3 Instrument structure and function

Balance rod adjusting parts: this part includes the thickness control device, height adjusting nut, front and back position adjusting nut, balance rod composition.

The height of the balance bar is determined by the thickness of the sample.

Before the test, the sample is inserted into the groove of the thickness control device, and the nut is adjusted by adjusting the height, so that the sample is stuck in the groove exactly.

When the sample is installed on the circular sample loading platform, the friction head is loaded into the balance bar, and its head supports the sample. At this point, the balance bar is basically kept parallel and only needs to be slightly adjusted (horizontal bubble is placed to see if it is horizontal).

Part of the standards require the test results to be concentric circles with different radii. The control nut before and after adjusting the position controls the scraping head and the loading sample

Distance from the center of the disk, resulting in nicks of different radii.

Pressure regulating parts: this part includes fixed weights, moving weights and balance bars.

The balance bar is marked with a scale from 0 to 500, with each bar representing 10g of pressure.

When in use, the middle cut line of the moving weight is aligned with the scale line on the balance, and the pressure applied on the sample surface is the pressure indicated by the cut line.

Sample loading unit: This part is composed of sample loading disk, fixing plate and fixing nut.

Place the sample on the loading disc and hold it down with a fixing plate, then fix it with a nut.

Control parts: including counter, start button, pause button and power switch composition.

Test steps

Sample preparation: The standard sample size is 100mm*100mm square, with edges and corners around it and a hole with a diameter of 6.5 in the middle, as shown in the figure below

Place the sample in the thickness control device and adjust the upper bolt to make the upper surface of the sample contact with the lower surface of the thickness control device.

Remove the sample and place it on the test plate, tighten the nut on the sample, lower the balance bar, and put the horizontal bubble on the balance bar to see if the balance bar is horizontal. If it is not, adjust the rear end bolt to make the bubble reach the level

Move the weight at the right end to the required pressure position and tighten the bolts at the back end of the weight so that it does not move during operation.

Power on, select the number of running turns of the experiment, and press the start button to carry out the test.

Taber 551 scratch tester before loading the sample, it is necessary to adjust the beam to the appropriate height according to the sample thickness.

Install the precision cutting tool on the beam and place it on the sample.

Start the instrument and rotate the turntable at constant speed to ensure accurate measurement results.

By changing the load of the cutting tool, you can evaluate the shear or scratch resistance of the material.

The Taber 551 scratch tester instrument's beam design allows it to be level with samples and turntables, and can be raised or lowered as needed.

In addition, the beam can be lifted in the air to facilitate the operator to remove the sample.

By changing the position of the sliding weight, the total load on the sample can be adjusted in the range of 0-1000g.

The cutting tool may be a tungsten carbide cutter or a conical diamond.

Taber 551 scratch tester test results can be randomly equipped with 10 x magnifier visual determination, users can also use high precision optical microscope observation.