A kind of preparation method of small particle size doped potassium-molybdenum alloy powder

Abstract

The invention discloses a preparation method of small-granularity potassium-doped molybdenum alloy powder. The method comprises the following steps of: sieving potassium-doped molybdenum dioxide serving as a raw material; placing the sieved raw material into a reduction furnace in a single temperature region; performing reduction treatment for 3.5 to 5.5 hours under the conditions of hydrogen flow of 10 m<3> / h to 14 m<3> / h and constant temperature of between 940 and 970 DEG C; and cooling along with the furnace to obtain the potassium-doped molybdenum alloy powder with the average granularityof 1.5 to 3.5 mu m. The method is simple; the reduction temperature is low; the reduction time is short; the granularity of the reduced molybdenum alloy powder is controlled not to enlarge and the volatile loss of the potassium element is controlled; the wastage rate of the potassium element is not more than 25 percent; the advantages of high efficiency and energy conservation are achieved; and the prepared potassium-doped molybdenum alloy powder can be sintered by the conventional sintering process and the subsequent treatment process is simple.

Description

technical field [0001] The invention belongs to the technical field of alloy materials, and in particular relates to a method for preparing small-sized potassium-molybdenum alloy powder. Background technique [0002] Potassium doping in molybdenum alloy can increase the recrystallization temperature of molybdenum alloy, thereby improving the high temperature toughness of molybdenum alloy. Potassium-doped molybdenum alloy powder is pressed and formed, sintered into molybdenum alloy billet, and prepared into molybdenum alloy wire by forging and drawing. , the obtained molybdenum alloy wire is mainly used to prepare molybdenum alloy filament support, its production added value is high, and the market demand is large. [0003] At present, potassium-doped molybdenum powder and molybdenum alloy powder are reduced in a multi-temperature zone reduction furnace. There is a certain temperature gradient between the temperature zones. 3 / h, the reduction time of molybdenum oxide is 8h-...

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Problems solved by technology

Generally, the sintered density of the K-doped molybdenum alloy powder pressed billet with a particle size of 4.0 μm is not higher than 9.5 g / cm 3 , when the particle size reaches 4.5μm~6.0μm, under the existing sintering process, the sintering density only reaches 8.8g / cm 3 ~9.1g / cm 3 , if you want to increase the sintering density, you need to increase the sintering temperature and prolong the sintering time, which not only increases the production cost, but also has a density of 8.8g / cm 3 ~9.1g / cm 3 The blanks are unqualified products and cannot be processed in subsequent forging, wire drawing, etc.

Therefore, the particle size of potassium-doped molybdenum alloy powder prepared by the existing reduction process is relatively large, which makes the existing sintering process and sintering equipment unable to adapt to the raw material of large particle size molybdenum alloy powder

At the same time, due to the high reduction temperature and long reduction time of the conventional reduction process, a large amount of potassium element is lost, and the actual potassium content in the prepared molybdenum alloy powder is much lower than the design content, which cannot meet the high temperature mechanical performance requirements of the wire.

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