It is a gray-black metal with metallic luster (body-centered cubic crystal). Melting point 3400 ℃. Boiling point 5555℃. The hardness of tungsten is the hardest among metals. The hardness of the sintered Tungsten Rod is 200~250, and the tungsten rod passed through the rotary hammer is 350~400. Soluble in mixed acid of nitric acid and hydrofluoric acid. Melt with a mixture of sodium hydroxide and sodium carbonate. Slightly soluble in nitric acid, sulfuric acid, aqua regia; insoluble in water, hydrofluoric acid, potassium hydroxide. Tungsten is available in two variants, a and B. At standard temperature and atmospheric pressure, type a is a stable body-centered cubic structure. Type B tungsten can only appear in the presence of oxygen. It is stable below 630 °C, and is converted into a-tungsten above 630 °C, and this process is irreversible. Tungsten is mostly used in the production of cemented carbide and ferrotungsten. Tungsten and chromium, molybdenum and cobalt form heat-resistant and wear-resistant alloys for making tools, metal surface hardening materials, gas turbine blades and combustion tubes, etc. Tungsten and tantalum, niobium, molybdenum, etc. form refractory alloys. Tungsten copper and tungsten silver alloys are used as electrical contact materials. High-density tungsten-nickel-copper alloy is used as a radiation shield. Metal tungsten wires, rods, sheets, etc. are used to make parts of light bulbs, electronic tubes and electrodes for arc welding. Tungsten powder can be sintered into filters of various porosity. FW-1 is used as raw material for large slab and tungsten-rhenium galvanic couple. FW-2 is used for contact alloy, high specific gravity shielding material. FWP-1 is used for plasma sprayed materials. Tungsten Powder,Low Carbon Tungsten Powder,Iron Alloy Tungsten Powder,Cast Tungsten Powder Jiangsu Lucky Metal Materials Co., Ltd. , https://www.luckymetalmoly.com
Li Yongwu, president of the China Petroleum and Chemical Industry Association, pointedly pointed out at the meeting that last year China's methanol production reached 4.4 million tons, an increase of 34.9% over the previous year, and imports were 1.359 million tons, with an apparent consumption of 573. 20,000 tons, an increase of 24.1%. Industry insiders estimate that most of the increase is mainly used in automotive fuel. In the first quarter of this year, a total of 1.207 million tons of methanol was produced across the country, an increase of 16.9% year-on-year, an import of 295,000 tons, and a domestic apparent consumption of 1.493 million tons, an increase of 8.2% year-on-year. Greatly slowed down. However, according to incomplete statistics, the capacity of methanol under construction reached a minimum of 13.77 million tons, plans to build 20.69 million tons, in addition to the pre-preparation phase of the project production capacity of 14.4 million tons. In the near future, the domestic methanol production capacity will reach more than 50 million tons, which requires 100 million tons of coal. According to the “Eleventh Five-Year Plan†of the national coal industry, by 2010, only 100 million tons of coal will be used for all chemical industries. He accordingly reminded to avoid blindly launching and to consider the issue of methanol development in a macroscopic and systematic way.
According to analysts at the conference, the continued rise in international oil prices will lead to the further development of China's coal chemical industry. The large pilot project for coal-to-liquids has started construction, and the large-scale coal-to-olefins pilot project will also be approved by the state. People in the industry also reminded that the development of coal chemical industry should not be allowed to come to the fore, especially coal to oil, coal to olefins, a large investment, in the large-scale devices in China before the success of the pilot project, should not be carried out blindly.
The meeting was held in Shihezi City, Xinjiang. The leaders of the National Development and Reform Commission, Xinjiang Production and Construction Corps, and Shihezi attended the opening ceremony. 400 experts and scholars from home and abroad attended the seminar, including senior executives from international famous companies such as Shell, Lurgi, and Topsoe. Gu Zongqin, Dean of the Petroleum and Chemical Planning Institute, and Shen Fei, Deputy Editor-in-Chief of China Chemical Industry, co-chaired the meeting.
Tungsten powder is the main raw material for processing powder metallurgy tungsten products and tungsten alloys. Pure tungsten powder can be made into wire, rod, tube, plate and other processed materials and certain shaped products. Tungsten powder mixed with other metal powders can be made into various tungsten alloys, such as tungsten-molybdenum alloy, tungsten-rhenium alloy, tungsten-copper alloy and high-density tungsten alloy. Another important application of tungsten powder is to make tungsten carbide powder, and then prepare cemented carbide tools, such as turning tools, milling cutters, drills and molds.
Yesterday morning, at the 2005 International Symposium on Carbon Technology and Clean Coal Technology Application co-sponsored by the newspaper and the Petroleum and Chemical Planning Institute, the participating experts issued a warning: The development of coal chemical industry should not be allowed to rise.