Preparation Method of Molybdenum Tungsten Lanthanum Wire

In order to further improve the strength, toughness and high temperature resistance of pure molybdenum wire, the researchers said that rare earth lanthanum and tungsten elements can be added to molybdenum wire. Normally, the higher the tungsten content, the higher the heat resistance of the molybdenum-tungsten lanthanum wire; but with the increase of the tungsten content, the product is also prone to cracks. Therefore, the following describes the new preparation method of molybdenum-tungsten-lanthanum alloy wire, and the specific steps are as follows:

1) Prepare raw materials according to lanthanum oxide 0.1-0.7%, tungsten 0.5-3.0%, and the rest are the mass fraction of high-purity molybdenum trioxide; 

2) Put high-purity molybdenum trioxide into a low-temperature reduction furnace, and perform a reduction in a hydrogen atmosphere, Obtain molybdenum dioxide powder; 

3) Mix molybdenum dioxide powder with lanthanum oxide and tungsten according to the proportion, and mix them evenly in a powder mixer; 

4) Put the doped mixture into a high-temperature reduction furnace and carry out the process in a hydrogen atmosphere Secondary reduction to obtain molybdenum-tungsten-lanthanum alloy powder; 

5) Put the molybdenum-tungsten-lanthanum alloy powder into a rubber sleeve, press it into a round bar shape in an isostatic press, and then sinter it at a high temperature of 2000±200℃ in an intermediate frequency induction sintering furnace. The molybdenum-tungsten-lanthanum alloy rod is obtained; 

6) the molybdenum-tungsten-lanthanum alloy rod is subjected to multi-pass rotary forging, drawing and straightening, and intermediate annealing to make molybdenum wire of the required specification. Note: The straightening process in step uses an improved straightening machine.

Compared with the existing production technology, the advantages of this preparation method are: 1) By doping lanthanum oxide and tungsten, the strength and high temperature resistance of the molybdenum alloy wire are significantly improved; 2) The straightening effect is improved by improving the straightening machine , to prevent the beating wear or scratches caused by the excessive clearance between the molybdenum wire and the spindle during the straightening process, and avoid affecting the quality of the product; 3) The improved straightening machine can be applied to the straightening of molybdenum wires of different specifications. More flexible and convenient.