Tungsten pipes can be directly extruded using sintered billets, and extruded or powder extruded sintered billets are also processed by spinning. Spinning can also produce tungsten shaped products. Large diameter bars are often produced using extrusion or rolling processes.

Cutting processing

Tungsten is hard and sensitive to notches, making it difficult to cut, requiring the use of hard alloy cutting tools. To prevent the occurrence of cutting cracks, the workpiece is often heated above the plastic brittle transition temperature for cutting, and the cutting operation program must be strictly controlled. The grinding of tungsten requires light grinding with a specific type of grinding wheel and cooling, otherwise it will cause cracking. Tungsten sheets with a thickness of over 0.2 millimeters need to be pre heated before stamping and shearing. Sheets with a certain thickness cannot be cut and often require grinding wheels to cut.

Tungsten plate rolling can be divided into hot rolling, warm rolling, and cold rolling. Due to the high deformation resistance of tungsten, ordinary rollers cannot fully meet the requirements of tungsten plate rolling, and special material rollers should be used. During rolling, the rollers need to be preheated, with a preheating temperature of 100-350 ℃ depending on different rolling conditions. The relative density of the blank (the ratio of actual density to theoretical density) is greater than 90% before processing, and the processing performance is good when the blank density is between 92% and 94%. The opening temperature of hot rolling is between 1350~1500 ℃, and improper selection of deformation process parameters can result in delamination of the billet. The starting temperature for warm rolling is 1200 ℃, and hot-rolled plates with a thickness of 8 millimeters can reach 0.5 millimeters after warm rolling. Due to the high deformation resistance of tungsten plates, the bending deformation of the roll body during rolling results in uneven thickness of the plate along the width direction. When changing the roll or rolling mill, the plate may crack due to uneven deformation in various parts. The plastic brittle transition temperature of the 0.5mm thick plate is still at or above room temperature, and the sheet is brittle. The sheet should be rolled into 0.2mm at 200-500 ℃. In the later stage of rolling, the tungsten sheet is thin and long. To ensure uniform heating of the sheet, graphite or molybdenum disulfide is often coated, which is not only conducive to the heating of the sheet, but also has a lubricating effect during processing.