How to use the micro hardness tester correctly?

Hardness is the property of some materials, micro hardness tester can be used to determine the hardness of the metal material, thus also can infer the strength of the metal and the degree of wear and tear, etc. The correct use of the micro hardness tester is particularly important for the accuracy of the measurement of metallic materials.

Here is the content list:

1. How does a micro hardness tester perform force determination?

2. Micro hardness tester how to use correctly?

How does a micro hardness tester perform force determination?

The correct force value of the micro hardness tester will directly affect the accuracy of the indicated value of the instrument. Because the micro hardness tester is using a small load (1kgf below) test, but also by the instrument space capacity limitations, so in a long time, the micro hardness tester force value determination failed to get a better solution, thus affecting the reliability and correctness of the micro hardness tester, but also affect the micro hardness tester manufacturing quality.

Micro hardness tester calibration regulations stipulate hardness tester load error, equal to and less than 100gf load, allowed within ± 1.5%, more than 100gf load error should be less than ± 1.0%, the degree of change of not more than 1.5% and 1.0% respectively. The micro hardness tester used in the past has the following three main force measuring devices:

(1) optical force tester

(2) modified mechanical balance

(3) resistance strain sensor force measuring device

The above three force measuring devices have been used for micro hardness tester load determination, but there are still more problems. An optical force tester and modified mechanical balance can be used to determine the load spindle using friction support micro hardness tester (such as BHX-1 type base stack micro hardness tester).

However, due to the large size, the use is extremely inconvenient. Especially for the micro hardness tester with elastic support of the loading spindle, it is impossible to use due to the "zero position" requirement.

Although the resistance-strain sensor force measurement device is better than the first two, to be widely used in the production and verification of micro hardness tester still has more disadvantages, such as complex device, large size, expensive, not easy to maintain, low efficiency, by the micro hardness tester space capacity limitations, for different loads need to adjust the table, etc.

Micro hardness tester how to use correctly?

1. The choice of load:

To hardness authenticity, micro hardness tester needs to choose the appropriate load, load selection principles have five points, the first point is the need to decide according to the external test items if the test object is a thin sheet, the choice of load need to consider the depth of the indenter and thickness; the second point is in the hardness test of the profile, the choice of load needs to be based on the length of the diagonal of the indentation and the width of the profile itself; if the fourth point is the choice of load for the average hardness test, we should try to choose some load is larger, because this can improve the correct rate of hardness test results; the fifth point is to consider the accuracy of the measurement rate, the choice of the load is determined, to choose a larger load.

2. Like the plane of the search:

a. Point of light to find the image method: the micro hardness tester lighting bulb on, the needle tip placed in the center of the circular aperture under the objective table, installed vertically, and then the lift table up, and then adjust the table and lift, so that the eyepiece among the appearance of a bright spot so far, which is the needle tip generated by the radiation point of light.

b. Edge finding method: To prevent damage to the micro hardness tester in the test, you need to use the edge finding method, the light point of the illumination lamp is aimed at the edge when the eyepiece appears half-bright half dark outline can be found through the lift like.

The hardness of the metal material corresponds to some other related properties of the metal material, hardness means that there is a certain resistance, the greater the resistance, the greater the hardness of the material. EBPu Electromechanical Equipment (Zhejiang) Co., Ltd. produces micro hardness tester with high quality and low price, which is the leader in the micro hardness tester industry.