External surface macular problem of arc type quartz crucible
After cleaning the pot can not see the macula, and heated to about three, Baidu appeared macular, because the reason is simple: no cleaning.
In order to solve this problem, you can start from two aspects: the 1 is the melting of sandblasting, cutting and transportation and storage process, do not touch the pollutants; such as dirty gloves, equipment oil, touch, dust, etc.. 2 is pickling. Hydrofluoric acid blister for a few minutes, rinse with deionized water, water resistivity is higher than 12 trillion, 14 or 16 better.
We often re wash the modified products, never found this problem. There may be cold coating or packaging operations problems