Inspection Requirements Of Metallographic Microscope And Solutions To Problems Found

- Apr 10, 2020-

1. Overview we often contact with general metallographic microscope, which is mainly used to measure the metallographic structure of metal watch machine. It is widely used and plays an indispensable role in the experiment and research of enterprises, metallurgy and other departments.

There are many manufacturers of metallographic microscope with different models and specifications, so there is no national, local and departmental verification regulation for metallographic microscope detection. Therefore, we test it according to national standards.

2. Inspection items, methods and technical requirements of metallographic microscope:

2.1 positioning error detector of objective lens converter:

(1) 10x cross eyepiece.

(2) The limit deviation between any two scribed lines is ± 0.005mm for a scriber with a scribed value of 0.01mm. Test method: install 40 times objective lens on the converter of the metallographic microscope to be tested, place 10 times cross eyepiece in the eyepiece cylinder, focus the 0.01mm reticle ruler placed on the stage clearly, make a reticle on the reticle ruler coincide with the center of the reticle in the eyepiece, and then rotate the objective lens converter to the left and right for multiple positioning (no less than 3 times Second), observe the offset of 0.01mm dividing ruler image, and take the Zui large offset value as the detection value. Technical requirements: no more than 0.02 mm.

2.2 when the objective lens is converted, the center deviation of the secondary image plane is: inspection tool:

(1) 10 times cross dividing eyepiece.

(2) Two character dash board. Test method: 10 times cross dividing eyepiece and each magnification objective were used to test on the inspected microscope, and the larger value of Zui was taken as the test value. Technical requirements: it does not cross the field of view when it is converted from 10x objective to other magnification objective.

2.3 deviation of rotation center of loading platform: inspection tool:

(1) 10 times cross dividing eyepiece.

(2) Two character dash board. Test method: use 10 times cross reticle eyepiece and 10 times objective lens to focus the cross reticle plate on the stage, move the cross reticle plate while rotating the stage, so that the image in the center of the cross line tends to Zui small circle, and take the straight diameter of Zui small circle as the test value. Technical requirements: the center of the secondary image of the microscope, Zui large offset is not more than 0.2mm.

2.4 deviation of cross line center of cross dividing eyepiece: inspection tool: cross dividing plate. Test method: on the Jiashun Weiye microscope, use the 10 times objective lens and the inspected cross dividing eyepiece to focus the cross dividing plate on the loading platform clearly, make the image in the center of the cross dividing plate coincide with the cross dividing plate eyepiece, then rotate the cross dividing eyepiece, and take the Zui big deviation in the center of the two cross lines as the test value.

Technical requirements: the cross line center of the cross dividing eyepiece shall coincide with the rising circle axis of the eyepiece, with a deviation of 0.01mm.

3. The problems found in the detection are serious in the imaging part.

3.1 optical system:

(1) The field of view is blurry or not as clear as the field of view.

(2) The contrast is not good.

(3) The objective lens is not in the same focus.

(4) Even if high voltage is used, the field of view is difficult to be distinct.

3.2 coarse and fine adjustment parts

(1) Heavy weight occurs when the coarse adjustment control knob rotates.

(2) The focal point in the observation is removed due to the natural lowering of the stage or the sliding of coarse-tuning.

3.3 binocular tube: the field of view of the binocular tube is inconsistent. The above problems are easy to correct, basically accurate and reliable.