Generally speaking, different types of samples need to use ball milling jars equipped with corresponding materials to ensure the grinding effect of the samples, so how can we choose the appropriate materials for the planetary ball mill?
Material selection principle of ball milling jar of planetary ball mill
Generally speaking, the selection of ball milling jar is mainly considered from hardness, corrosion resistance, pollution and vacuum grinding.
First of all, the hardness of the sample needs to be smaller than that of the ball mill and the grinding ball. Otherwise, the sample will wear the ball mill jar and the grinding ball during the ball mill process, which will cause pollution to the sample, and at the same time, it cannot achieve good grinding effect. Therefore, when choosing the ball mill jar and the grinding ball, we should choose the ball mill jar and the grinding ball with the same or greater hardness than the sample. In the present commonly used ball milling jars of several materials, silicon carbide, zirconia, agate, corundum and stainless steel are arranged in order of hardness from high to low.
The second is corrosion resistance. In the laboratory of food, medical treatment and beauty industry, there will be some strong acid-base samples, which have strong corrosivity. If the ball mill jar with unsuitable material is selected, it will be corroded and damaged, and the sample will be polluted. For corrosive samples, we generally choose polytetrafluoroethylene (PTFE), polypropylene (PP) and other polymer materials made of ball milling jar, which can prevent the sample from corrosion to the jar.
Then we should consider whether the ball mill jar will pollute the sample. When we use the ball mill jar, we should not only see the particle size effect of the material, but also pay attention to whether the sample will be polluted by the ball mill jar during the ball mill process, so as to prevent other impurities from being mixed into the sample and affecting the experimental results.
In addition, in some special cases, some samples need to avoid contact with oxygen and other gases in the air during grinding, and need to be ball milled in vacuum or filled with inert gas. At this time, a special vacuum ball milling jar is needed. The vacuum ball milling jar is generally made of stainless steel. If the sample cannot be contaminated by metal or will cause corrosion to stainless steel, we need to embed other materials in the inner wall of the vacuum stainless steel ball milling jar to avoid direct contact between the sample and stainless steel, and achieve vacuum grinding.
The selection principle of the ball milling jar of the planetary ball mill used in the laboratory is shared with you here. There are many kinds of ball milling jar materials. We consider the above four aspects when selecting and using, in order to achieve good grinding effect.