As we all know, there are various kinds of mediums in the world. For example, the stainless steel must be spark-resistant, non-magnetic steel in the 300-series. Alloys 304 and 316 are the most common stainless steels. However, high-density alumina ceramic medium is one of the most widely used medium in ball mill. Nowadays, people pay more attention to the safety of anything. What i want to emphasize is that there is an ongoing discussion and debate about what is the 'safest' medium used in ball mill. Every medium has both advantages and disadvantages. Once the milling mixed compositions like black powder is mixed in the mill that the dangers arise. It is obvious that we don't want sparks generated in the ball mill during the process. Ceramic is hard, and it does not easily wear out, but some kinds of ceramic do generate spark. And some people have proved that when pieces of ceramic medium collide each other in the dark, little sparks can be seen. Others say that there is just little luminous sparks and they don't think it a danger in milling.ore vibrating feeder:http://www.hxjqchina.com/product-list_14.html Lead or brass is reliably the only really spark-free medium and is regarded as the standard for milling comps like BP. But lead is soft and will wear down just a while. And it is also easy to lead a Lead poisoning. At the same time, there are many reports about lead poisoning recently, so we should take serious. Lead medium probably will continue to be used more than any other mediums in amateur pyrotechnic milling. Comprehensive intro to Ball Mill: Ball mills are extensively applied in mining, constructing material, smelting, road and chemical. It may be the crucial gear for grinding following the crush process. Energy-Saving Ball Mill Features: one It can be an effective device for grinding a great deal of difficult components into good powder; two There are two methods of grinding: the dried out way and also the wet way; three might be divided into tabular sort and flowing sort based on diverse expelling mine; four to utilize the ball mill, the materials being soil is loaded to the neoprene barrel that consists of grinding media; five since the barrel rotates, the materials is crushed among the personal pieces of grinding mass media that combination and ball mill crush the item into good powder more than a period of time of time. In one word, nothing is perfect. Any thing has both advantages and disadvantages. We should take good use of its advantages and avoid its disadvantages. ball mill:http://www.hx-crushers.com/