1.S70-S930 2.Hardness : HRC 40~50 3.sandblast media 4.surface treatment Application:1. Removing the sand, cleaning the scales & brighten the surface on the cast steel, casting & forging & heat treatment parts etc.2. Shot blasting steel plate & H bean & building material. 3. Etching processes before the rubber gluing.4. Roughing & cleaning the stone material.5. Cleaning the crinkle, spots, dirt ...