... internal-crack. 1Grade: W1, W2, WAL1, WAL2, WAL32. Purity: W≥99.95%3.Characteristic:Melting Point: 3410 DCBoiling Point:5927 DC ... 50-200mm ;4.Certificate: ISO9001:20085. Product Feature: high-purity, high-density, no internal-crack.6. Dimensions and tolerance(According ... working environment of tungsten crucible is above 2000°C. For sapphire crystal growth furnace, high-purity, high-density, no internal- ...