Processing method of tungsten filament and additive thereof

Abstract

The invention involves a tungsten filament production method and it special additives, the method includes the following steps: weighing certain tungsten oxide and putting into reactor, adding additives which weight percentage is 0.8 ~ 1.2% relative to tungsten oxide, adding aluminum nitrate; adding water and mixing uniform, drying; hydrogen gas deacidizing and preparing doping tungsten powder in multi-pipe furnace, the dew-point of hydrogen gas <=-40DEG C, the hydrogen gas flow is 1.5-1.7 m3/h, load-canoe amount is 400-500 g, push-canoe velocity is 1.5-2.5 canoe/h, the first deacidizing temperature is 600-650DEG C and the second deacidizing temperature is 800-900DEG C, the prepared doping tungsten powder is produced to tungsten strip through profiling and one time incipient fusion sintering, then is produced to thermos table tungsten wire through pressure processing; the invention has advantages of high production efficiency, high content of potassium in tungsten filament, good resistant temperature property and free-fluohydric acid pollution.

Description

technical field [0001] The invention relates to a metal production method and its additives, in particular to a tungsten wire production method and its additives. Background technique [0002] At present, the method of producing high-temperature resistant tungsten wire at home and abroad generally adopts the following method, adding 0.03-0.1% of alumina, 0.3-0.55% of potassium oxide, and 0.3-0.4% of tungsten oxide to tungsten oxide. Silicon oxide, silicon dioxide and potassium oxide are added in the form of potassium silicate solution. Potassium silicate is formed by the reaction of potassium hydroxide and silicic acid. Aluminum oxide is added in the form of aluminum nitrate solution. Reduction of hydrogen in a tube furnace to produce doped tungsten powder requires: hydrogen dew point ≤ -40°C, hydrogen flow rate of 1.5-2.5 cubic meters per hour, boat loading capacity of 250-320 grams per boat, and boat pushing speed of 2 boats per hour , the primary reduction temperature is...

AI Technical Summary

Problems solved by technology

[0004] 1. Doped tungsten oxide is difficult to reduce, less loading, long reduction time, low production efficiency, and poor particle size distribution of tungsten powder. The specific performance is that the average particle size of tungsten powder changes greatly before and after pickling, the crystallization of sintered tungsten bars is uneven, and the cross section appears Frame crystal, large crystal, poor product performance, poor consistency, low potassium content in tungsten bars, potassium content <80ppm, poor high temperature resistance, unstable quality, potassium content in tungsten bars fluctuates around 50-70ppm, it is difficult to control

[0005] 2. A large amount of alumina, potassium oxide, and silicon dioxide are added to tungsten oxide, which causes the enrichment of aluminum in the tungsten wire to form a brittle point, which affects the processing performance and low-temperature winding performance of the tungsten wire. Doped tungsten powder passes through hydrogen Fluoric acid pickling, resulting in the loss of doped tungsten powder and environmental pollution