| The metallic element tungsten is not found free in nature, but in several ores. Tungsten is steel-gray to tin-white in color and, when very pure, can be forged, spun, drawin, and extruded. Impure tungsten is very brittle and difficult to work
                . Tungsten is very resistant to corrosion and stable in dry air at room  temperature. Tungsten's melting point exceeds that of all other metals and it  has the lowest vapor pressure. At temperatures over 1650°C, tungsten has the  highest tensile strenghth 
                  
                    | Grade
 | W (%,Min.)
 | Impurities (%, Max.    ) |  
                    | Al | As | Bi | Ca | Mg | Cd | Co | Cr | Cu | Fe | K |  
                    | FW-1 | 99.9 | 0.001 | 0.0012 | 0.0001 | 0.002 | 0.001 | 0.0003 | 0.001 | 0.0015 | 0.0008 | 0.004 | 0.002 |  
                    | FW-2 | 99.8 | 0.0015 | 0.0015 | 0.0003 | 0.003 | 0.0015 | 0.0003 | 0.001 | 0.0015 | 0.001 | 0.008 | 0.003 |  
                    | Na | Mn | Mo | Ni | P | Pb | Sb | Si | Sn | Ti | V | C | - |  
                    | 0.002 | 0.0007 | 0.004 | 0.002 | 0.001 | 0.0001 | 0.0003 | 0.002 | 0.0001 | 0.0008 | 0.0008 | 0.005 | - |  
                    | 0.003 | 0.001 | 0.01 | 0.004 | 0.002 | 0.0003 | 0.0005 | 0.004 | 0.0003 | 0.001 | 0.001 | 0.01 | - |  Divided into 14 grades according to Fsss.size  
                  
                    | Grades | Fsss.(µm) | O2 ( %,Max. )  |  
                    | 04 | BET:<0.10 | 0.80 |  
                    | 06 | BET:0.10~0.20 | 0.50 |  
                    | 08 | Fsss: ≥0.8~1.0 | 0.40 |  
                    | 10 | Fsss:>1.0~1.5 | 0.30 |  
                    | 15 | Fsss: >1.5~2.0 | 0.30 |  
                    | 20 | Fsss: >2.0~3.0 | 0.25 |  
                    | 30 | Fsss: >3.0~4.0 | 0.25 |  
                    | 40 | Fsss: >4.0~5.0 | 0.25 |  
                    | 50 | Fsss: >5.0~7.0 | 0.25 |  
                    | 70 | Fsss: >7.0~10.0 | 0.20 |  
                    | 100 | Fsss: >10.0~15.0 | 0.20 |  
                    | 150 | Fsss: >15.0~20.0 | 0.10 |  
                    | 200 | Fsss: >20.0~30.0 | 0.10 |  
                    | 300 | Fsss: >30.0 | 0.10 |  Packing:In iron drums lined with double plastic bags of 50 or 
			  100 kgs net each.Note:Any particular requirements to the products can be 
				discussed.
 If you have any interest in our products, please feel free to contact us by   email: sales@chinatungsten.com or   by telephone:
				+86 592 5129696. |