Vickers hardness tester is a combination of precision machinery and optoelectronic computer software, the new hardness tester can be used for Vickers or Knoop hardness test, by measuring the diagonal value into the comprehensive calculator, calculate the hardness value Th
Vickers hardness is the optical system, the total magnification of the optical system is 100 ×, 200 × or 400 ×, so the top position of the indenter if there is a slight deviation, it will lead to significant deviation from the center of the dent. Equipment transport, vibration and loading and unloading indentation and other reasons will cause this deviation. Hardness working conditions
A at room temperature (23 ± 5) ° C;
B solid foundation;
C in a vibrant environment
D around no corrosive media;
E indoor relative humidity of not more than 65%.
Not packaged and installed
Vickers Hardness Tester The name of each item on the host
1. Adjustment screw 2. Rotary wheel 3. Screw 4. Test stand 5. Indenter 6. Eyepiece 7. Goggle 8. Top cover
9. Camera cover 10. Rear cover 11. Handwheel 12. Power switch 14. Lamp source 15 Left drum
16. Right Drum 17. Turntable 18.10х Goal 19.20x Target 20. Emergency stop button
2.6 Open the top cover (8), remove all the belts secured to the lever, and then cover the top cover.
2.7 Remove the test bed (4) from the accessory box and place it in the hole of the screw (3). Insert one end of the eyepiece (6) into the eyepiece
The tube hole is inserted last.
2.8 Illegal operation or current problem can press the emergency stop button
Install 3 weight groups
3.1 Open the rear cover (10) and remove the gauze between the boom (19) and the fork (20), remove and wipe the weight in the accessory box. Move the handwheel (11) to the 1kgf position so that the fork (20) is horizontal.
3.2 The weight (1), weight 2 (22), weight 3 (23) and weight 4 (24) are placed on the fork (20), and then the handwheel (11) is rotated to 50 kgf, (11) to 1 kgf in the wall to see if the double-sided pin on the weight is placed in the groove of the fork (20) and placed on the rear cover (10).
Vickers hardness Vickers hardness is expressed as HV, Vickers hardness symbol HV in front of the hardness value, followed by the test force value. Standard test retention time is 10 ~ 15S. If the selected time is outside this range, keep the hold time after the force value. E.g:
600HV30- indicates a test force of 294.2N (30kg) and a holding time of 10 to 15S. 600HV30 / 20- indicates a test force of 294.2N (30kg) at a holding time of 20S and a hardness of 600. Using the regular quadrilateral pyramid diamond indenter, under the action of the sample force into the sample surface, to maintain the specified time to remove the test force, measuring the surface of the sample indentation diagonal length. The test force divided by the indentation surface area is the Vickers hardness value. Vickers hardness is calculated as (3-1):
HV = constant × test force / indentation area ≈0.1891F / d2 (3-1) where: HV ---- Vickers hardness symbol; F ---- test force, N;
D - indent the two diagonal d1, d2 arithmetic mean, mm is actually based on the diagonal length d through the lookup table to obtain Vickers hardness value.
National standard to provide Vickers hardness indentation diagonal length range 0.020 ~ 1.400mm 3. Vickers hardness test classification and test force selection
Vickers hardness test according to the size of the test size, divided into three tests, namely Vickers hardness test, Vickers hardness test and Vickers hardness test. Table 3 Three Methods for Vickers Hardness Testing Vickers Hardness Tests can be used to test many values. Vickers hardness test force Vickers hardness test force depends on the type of sample selected, the thickness of the sample and the expected range of hardness. The standard specifies that the thickness of the sample or test layer is at least 1.5 times the length of the indentation diagonal. There is no visible trace on the back of the sample. Advantages of Vickers Hardness Test:
Vickers hardness tester Vickers hardness test is a square, clear line of light, diagonal measurement of high precision, so the Vickers hardness test is commonly used hardness test method of the highest accuracy, its repeatability is also very good, which than Brinell hardness Excellent hardness.