洛阳宝珠砂（电熔陶粒）粒型：球型，角形系数=1.1；耐火度=1830℃，粒度6目－320目，它耐高温，易溃散，热膨胀量小，不破碎，再生性能好，具有良好的铸造性能。广泛运用于各种铸造方式，砂型铸造，特种铸造（熔模、实型、消失模等）；也用于喷丸（铝、铜铸件）、低膨胀耐高温腹膜砂、消失模涂料的生产，适合使用各种铸造粘结剂。

　　宝珠砂价格只有锆英砂1/3，铬铁矿砂1/2；产品比对列表：

　　Baozhu sand is new casting sand developed by our engineers and technicians based on more than ten years rescarch and experiment. The achievement is appraised by foundry experts as a revolution in casting sand.

　　Baozhu sand has good heat-resistance, low heat expansion, desirable collapsibility and good reusability; it doesn,t break during process and has good foundry characters, Now, It is used in all types of casting method like sand casting, investment casting. It ia also applicable to sand blasting, resin sand manufacturing, and suitable for all binders.

　　Because of its pptimum combibination of cost and foundry characters, with it,s rapid growing in recent years, Baozhu sand is widely used in sll linds of ferrous snd no-ferrous metal casting as a best substitute of chromite sand.

　　As the inventor of Baozhu sand, we are vety proud that it has been exported to Japan,France, South Kouth and other countries, where it,s called as “Green Bead”.

　　Physical property:

　　1. Grain shape: Round

　　2. Colour:Black Brown

　　3. Grain Size: 20/30, 30/40, 40/70, 50/100, 70/140, 100/200;4. Density; 1.95-2.05(g/cm≥)

　　5. Refractory; ≥1790℃

　　6. Heat Conductivity: (1200℃)5.27W/M。K

　　7. Linear Expansion: (20-1000℃)6X10-6/℃Requirements for Binder: Less than 30-50 resin usage (comparing with other angular sand), Sodium Silicate≤4％ （Sodium Silicate+Carbon Dioxide）