Nanocomposite W-2% ThO2 Electrode Materials

With excellent performance , the traditional W-2% ThO2 electrode is a widely used hot cathode material , swaging method is a widely used method of industrialization . Swaging method , also known as radial or rotary hammer forging method , it is actually a special form of forging . Swaging machine works by two or more blocks of one hand forging die forging billet axis surrounded by high-speed rotation , on the other hand on the billet for forging, forging a frequency of approximately 6800 to 12,000 times / min, thereby the billet deformation. Melting down the sintered article W , first through swaging , and then stretched to the required finished wire . Swaging and drawing , has the following advantages: ( 1 ) The stress state is good. In the rotary forging , the billet at a reasonable process conditions by three to compression stresses, swaging force changing periodically , but not outside the friction . More moderate deformation of the metal , so suitable for processing low plasticity billet ; ( 2 ) Can effectively improve the microstructure and properties of metals . With coarse and fine grain cross porous vertical melt distribution billet by swaging broken into fine grain , and with the mouth of the total increase in the degree of deformation , the messy arrangement of porous vertical melt coarse grain structure gradually transformed into dense aligned fine grain structure . Therefore, the metal density , plasticity and strength and so has been significantly improved, so as to produce qualified Rod and smoothly brushed created favorable conditions ; ( 3 ) Swaging blooming with other methods ( eg , rolling method and extrusion method ) , also has equipment compact and easy to operate , as well as the advantages of low consumption deformation . In the rotary forging process, due to the deformation of the blank is not reactive, and friction , and thus the required motor power is only about 1.5-2.0kW .

However , the material processed by swaging , W cathode of the rod-shaped or needle ThO2 , as coarse grains , serious deterioration of the cathode performance. Authors' by high energy ball milling , and then sintered , a new nano-composite W-2% ThO2 cathode material was developed to put success. The materials ThO2 particle size less than 100nm, showing better than the same grade commercial arcing electrodes and anti- arc ablation performance. However, as the process is less than the maximum compressive stress 50MPa, so the relative density of the material is only 94.5% , much lower than the conventional cathode ( fully dense ) , fracture toughness is also poor. The disadvantage of the method is the high cost , not suitable for industrial production. Thus , limiting the application of this new cathode material .

In order to make the performance of this material has been further improved , the authors were prepared using swaged nanocomposite W-2% ThO2 cathode material , and to explore the possibility of industrial production , it truly out of the lab .


Tungsten Alloy Manufacturer & Supplier: Chinatungsten Online - http://www.tungsten-alloy.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn

• < Prev
• Next >