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31.
Konstantin M. Klimov Ivan I. Novikov 《材料研究与应用》2005,(3):530-532
Electrostimulated deformation of metals and alloys, using groove or smooth rolling, requires that several important conditions are satisfied. (1) The deformation site must geometrically overlap with the flow of electric current passing through a strip between the rolls; (2) The density of direct or alternating electric current supplied to deformation site must be sufficiently high (of an order of 104-106A/cm2 ); (3) An efficient heat removal from the deformation site must be achieved. In general, the temperature of a strip must be within the range of 100-300℃. (4) The electric resistance at the roll-strip interface must be minimized. Our recent studies also indicate that the electrostimulated rolling in the shortcut regime is a further condition for obtaining high quality rolling of metals. In this regime, the rolls are placed in physical contact even in the absence of a strip that ensures an uninterrupted passage of electric current between the rolls.Provided that the aforementioned conditions are met, the plastic rolling deformation of various metals and lloys, including the most refractory and deformation resistant ones such as tungsten, molybdenum,their allows with rhenium, becomes possible. A single pass through the rolls is usually sufficient to deform a strip by about 50%- 70% as is the case for tungsten. Significantly, the temperature in the deformation site does not exceed 150-200℃.In our opinion, excellent results for electrostimulated rolling obtained by us are related to new previously unknown behavior of metals and alloys, being subject to pressure treatment and rolling. 相似文献
32.
Mining Institute, Siberian Branch, Academy of Sciences of the USSR, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 6, pp. 57-64, November-December, 1991. 相似文献
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36.
俄罗斯诺里尔斯克选矿厂选矿新工艺的创立 总被引:1,自引:0,他引:1
由于近年来塔尔纳赫斯克选矿厂的生产能力已达到能够处理塔尔纳赫斯克矿山开采的全部富的致密块状硫化矿石。所以,诺尔斯克选矿厂多余的生产能力可以用来分别处理过去同时开采的浸染状矿石和铜矿石,以及处理过去堆存的磁黄铁矿精矿,处理浸染状矿石除采用常规的浮选工艺外还采用闪速浮选和从浮选尾矿中重选回收贵金属;在铜矿石处理中采用正优先浮选流程;在处理堆存的磁黄铁矿精矿时采用贵金属重选预选和给矿磨矿擦洗。 相似文献
37.
Kirbitova N. V. Eliseev N. I. Kologtygina G. V. Pevlina L. A. 《Journal of Mining Science》1980,16(4):378-380
Journal of Mining Science - 相似文献
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39.
M. V. Kurlenya 《Journal of Mining Science》1993,28(4):393-396
40.
Interaction of Bacillus polymyxa with calcite, hematite, corundum and quartz resulted in significant surface chemical changes not only of the cells but also in the minerals. Both the cell surfaces as well as quartz particles were rendered more hydrophobic after mutual interaction, whilst the rest of the minerals exhibited enhanced hydrophilicity after interaction with the bacteria. The bacteria were also observed to be capable of dissolving calcite, hematite and corundum and biosorbing the dissolved metal ions to varying extents. An excess of polysaccharides could be observed on biotreated calcite, hematite and corundum while the predominance of a protein-based metabolic product was evident on quartz surfaces. The utility of bioprocessing in the beneficiation of the above minerals through bioflotation and bioflocculation is demonstrated. 相似文献