洛氏硬度計(jì)硬度值調(diào)整注意事項(xiàng)

　　硬度計(jì)的種類有洛氏硬度計(jì) 、顯微硬度計(jì)、布氏硬度計(jì)、維氏硬度計(jì)、里氏硬度計(jì)、邵氏硬度計(jì)、肖氏硬度計(jì)、巴氏硬度計(jì)、水果硬度計(jì)、水泥硬度計(jì)等 。

　　現(xiàn)列舉如下：

　　1、硬度計(jì)本身會(huì)產(chǎn)生兩種誤差：一是硬度值誤差;二是硬度值重復(fù)性誤差。對(duì)第一種誤差，在測(cè)量前需用標(biāo)準(zhǔn)塊對(duì)硬度計(jì)進(jìn)行校準(zhǔn)。對(duì)洛氏硬度計(jì)校正結(jié)果，差值在±2之內(nèi)合格。在硬度值調(diào)整時(shí)，首先調(diào)整高值和底值，新機(jī)器一般可以調(diào)整到±0.5-1之內(nèi)。對(duì)第二種誤差，就要全面檢查儀器的各個(gè)環(huán)節(jié)，如儀器是否水平、砝碼位置是否正確等。

　　2、在更換或砧座時(shí)，注意接近部位要擦干凈。換好后，要用一定硬度的鋼樣測(cè)試幾次，直到連續(xù)兩次所得硬度值相同為止。目的是使壓頭或砧座與試驗(yàn)機(jī)接近部分壓緊，接近良好，以免影響試驗(yàn)結(jié)果的準(zhǔn)確性。

　　3、 硬度計(jì) 調(diào)整后，開始測(cè)量硬度時(shí)，第一個(gè)測(cè)試點(diǎn)不用。因怕試樣與砧座接近不好，測(cè)得的值不準(zhǔn)確。特第一點(diǎn)測(cè)試完，硬度計(jì)處于正常運(yùn)行機(jī)制狀態(tài)后再對(duì)試樣進(jìn)行正式測(cè)試，記錄測(cè)得的硬度值。

　　4、在試件允許的情況下，一般選不同部位至少測(cè)試三個(gè)硬度值，取平均值，取平均值作為試件的硬度值。

　　5、對(duì)形狀復(fù)雜的試件要采用相應(yīng)形狀的墊塊，固定后方可測(cè)試。對(duì)圓試件一般要放在V形槽中測(cè)試。

　　6、加載前要檢查加載手柄是否放在卸載位，加載時(shí)動(dòng)作要輕穩(wěn)，不要用力太猛。加載完畢加載手柄應(yīng)放在卸載位置，以免儀器長(zhǎng)期處于負(fù)荷狀態(tài)，發(fā)生塑性變形，影響測(cè)量精確度

Rockwell hardness tester hardness value adjustment matters needing attention

The types of hardness tester are Rockwell hardness tester, micro hardness tester, Brinell hardness tester, Vickers hardness tester, Leinell hardness tester, Shore hardness tester, Shore hardness tester, Barinell hardness tester, fruit hardness tester, cement hardness tester and so on.

The list is as follows:

1, hardness tester itself will produce two kinds of error: one is the hardness value error; Second, repeatability error of hardness value. For the first error, the durometer should be calibrated with a standard block prior to measurement. The calibration result of Rockwell hardness tester is qualified within ±2. When the hardness value is adjusted, first adjust the high value and the bottom value, the new machine can be adjusted to ±0.5-1. For the second error, it is necessary to check all aspects of the instrument, such as whether the instrument level, weight position is correct.

2, in the replacement or anvil, pay attention to the close part to wipe clean. After the replacement, the steel sample of a certain hardness should be tested several times until the hardness value is the same for two consecutive times. The purpose is to make the head or anvil seat and testing machine close to part of the compression, close to good, so as not to affect the accuracy of the test results.

3. After the hardness tester is adjusted, the first test point is not used when the hardness is measured. For fear of specimen and anvil close to bad, measured value is not accurate. After the test of the first point, the hardness tester is in the state of normal operation mechanism, and then the specimen is formally tested, and the hardness value measured is recorded.

4. Under the condition that the specimen is allowed, different parts are generally selected to test at least three hardness values, and the average value is taken as the hardness value of the specimen.

5, the shape of the complex specimen to use the corresponding shape of the pad block, fixed rear can be tested. The circular specimen is generally tested in a V-shaped groove.

6, before loading to check whether the loading handle is placed in the unloading position, the loading action should be light and steady, do not force too hard. After loading, the loading handle should be placed in the unloading position, so as to avoid the plastic deformation of the instrument under load for a long time, which will affect the measurement accuracy