CN1425782A - Metal oxide blended silver-tin dioxide electric contactor material and its preparing method - Google Patents

Abstract

The present invention belongs to the preparation techonlogy of electric alloy material. The electric contactor material consists of Ag 85-90 wt%, SnO2 5-20 wt% and blended metal oxide 0.5-8 wt%. The blended metal oxide is ZrO2, ZnO, TiO2, MnO2, WO3 or Sb2O3. The electric contactor material is prepared through coating oxide through chemical plating with plating liquid with dispersant, mixing the coated pwoder and silver powder, pressing, sintering, hot extruding, cold drawing or cold rolling, and making rivet or punched product. The present invention has the features of homogeneous oxide dispersion, good fusion welding resistance, high arc corrosion resistance and less electric transfer. The production process is simple, practical, low in cost and suitable for large scale production.

Description

Blended metal oxide silver-tin dioxide electrical contact material and preparation method thereof

Technical field

The present invention relates to electric contact material and preparation technology thereof.

Background technology

Electrical contact is the contact member of electric switch, instrument, is the critical material of electrical equipment such as contactor, rly., plays a part connection, disjunction and transmission current, is widely used in the equipment such as electric power, telecommunication system and household electrical appliances control machinery.That uses in a large number in the domestic and international all kinds of low-voltage apparatuses at present is electrical contacts such as AgCdO, AgNi, over-all propertieies such as AgCdO processing characteristics, contact resistance, anti electric arc corrosion are better, therefore, the AgCdO contact material is widely used, but because the AgCdO material produces the cadmium poison inevitably in production, use, cause environmental pollution, and along with in low-voltage apparatus miniaturization, high reliability, the long-life process, shortcoming such as the AgCdO material also exposes its melt resistance can be poor, the anti-electric-arc scaling loss is serious.The silver-tin electrical contact material is a kind of non-toxic material that fast development is in recent years got up, it has Heat stability is good, anti-arc erosion and resistance fusion welding can be good, use range can reach 10-1000A, thereby guarantee the reliability of electric operation, improving work-ing life, is the ideal material that replaces deleterious Agcdo at present in contactor, rly. and low-tension switch.

The interior oxidation of many at present both at home and abroad employings adds the indium method and produces sliver oxidized tin contactor materials; But there are problems such as production cost height, complex process, productivity, yield rate, can not satisfy the requirement of domestic electrical equipment and automobile market far away electrical contact.Making the siller tin oxide contact with powder metallurgic method is in recent years developed fast, but overall view As-Is, still have the following disadvantages with powder metallurgic method manufacturing silver tindioxide electrical contact: (1) technology more numerous and diverse (2) tindioxide powder distributes even inadequately, affects the workability of material and the stability of electrical property.

Summary of the invention

The objective of the invention is to overcome the weak point that above-mentioned powder metallurgic method is produced the contact of siller tin oxide, a kind of adulterated metal oxide silver-tin dioxide electrical contact and preparation method thereof is provided.This electrical contact has the specific conductivity height, and homogeneous microstructure is careful, interface bond strength is high, the characteristics of anti-melting welding, anti-electrical arc erosion, and its preparation technology is simple, cost is low.

The present invention is realized by following technical proposals.Its electrical contact material is made up of silver, tindioxide and adulterated metal oxide.Wherein tindioxide content is that 5～20wt%, adulterated metal oxide content are 0.5～8wt%, and all the other are silver.

Blended metal oxide is one or both of zirconium white, zinc oxide, titanium oxide, weisspiessglanz or Tungsten oxide 99.999 powder in the above-mentioned electrical contact material.

The preparation method of above-mentioned electrical contact material is characterized in that comprising the steps:

(1) one or both ratio and the tindioxide powder with 0.5～8wt% with zirconium white, zinc oxide, titanium oxide, weisspiessglanz or the Tungsten oxide 99.999 powder of blended metal oxide mix with 99.5～92wt%, put into sintering oven 900～1300 ℃ of sintering 3～10 hours, preparation doped tin dioxide powder end;

(2) the doped tin dioxide powder end being put into concentration is 0.8～1.2N AgNO ₃In the solution, it is dispersion agent that this solution adds trolamine, and add-on is 10～80ml/kg, prepares silver-colored coating-doping tindioxide powder;

(3) will be set by step (2) silver-colored coating-doping tindioxide powder of obtaining mix with silver powder, mix at 90: 10 by the last weight ratio of silver and doped tin dioxide powder;

(4) with the pressure forming of the mixed powder of step (3) at 150-400MPa, at 750-900 ℃, sintering 2-8hr, preparation electrical contact material.

Major advantage of the present invention is, doped metallic oxide in the tindioxide powder, has been improved the electroconductibility of material, helps reducing the contact resistance of material.The coating-doping tindioxide powder that adds dispersion agent in chemical plating fluid can obtain epigranular, high dispersing, powder that interface binding power is strong, has improved the ability of the anti-melting welding of contact, anti-electrical arc erosion and anti-electrotransfer.Raw materials used being easy to get, technology is simple, and cost is lower, is suitable for industrial-scale production.

Embodiment

Embodiment one:, mix with the tindioxide powder through grinding, sieving with titanium oxide (1), and the ratio of tindioxide and metal oxide is 98: 6wt% through 1000 ℃ of high temperature, diffusion-sintering in 10 hours, obtains adulterated TiOx tindioxide composite powder after the grinding.(2) with the doped tin dioxide powder end, put into silver ammino ion solution, put into 60ml trolamine/kg (Ag) again, stirred 20 minutes, and added the continuous stirring of hydrazine hydrate solution, obtain silver-colored coated metal oxide composite powder, through washing pH=7,100 ℃ of oven dry, obtain silver-colored cladding powder.(3) with silver powder and coating-doping tindioxide powder with the mixed of 90: 10 (wt%) 6 hours, through the 300MPa embryo of colding pressing, 850 ℃ of sintering sintering 3hr; Hot extrusion (extrusion ratio is 200); Cold drawing is to final size; The riveter nail.

Silk material density is 9.7-10.1kg/cm ³, resistivity is 2.1-2.6 μ Ω .cm,

Hardness is HB700-1100Mpa, and tensile strength is 220-350Mpa, and unit elongation is 8-26%.

Embodiment two: mix with the tindioxide powder with zirconium white, titanium oxide (1), the ratio of tindioxide and zirconium white, titanium oxide is 90: 4: 1wt% (weight ratio), through 1200 ℃ of high temperature, diffusion-sintering in 6 hours, obtain the doping stannic oxide composite powder after the grinding.(2) the doped tin dioxide powder end is put in the silver ammino ion solution, adds 40ml trolamine/kg (Ag) and stir half an hour, add hydrazine hydrate solution and continue to stir, through wash pH=7, oven dry obtains silver-colored cladding powder.(3) with silver powder and coating-doping tindioxide powder with 90: the 10wt% mixed, mixed powder 6 hours, through pressed compact (pressure 300Mpa), 850 ℃ of sintering 3hr; Hot extrusion (extrusion ratio is 200); Cold drawing is to final size; The riveter nail.

Claims (3)

1, a kind of blended metal oxide silver-tin dioxide electric contact material is characterized in that it is made up of silver, tindioxide and blended metal oxide; Each components contents is a silver: 85～90%, and tindioxide 5～20%, blended metal oxide 0.5～8%.

2, by the described blended metal oxide silver-tin dioxide of claim 1 electrical contact material, it is characterized in that: adulterated burning is one or both of zirconium white, zinc oxide, titanium oxide, weisspiessglanz or Tungsten oxide 99.999 powder.

3, a kind of preparation method: it is characterized in that by the described blended metal oxide silver-tin dioxide of claim 1 electrical contact material:

(1) powder of preparation blended metal oxide and tindioxide, one or both ratio and tindioxide powder with 0.5～8wt% of zirconium white, zinc oxide, titanium oxide, weisspiessglanz or Tungsten oxide 99.999 powder are mixed with 99.5～92wt%, put into sintering oven 900～1300 ℃ of sintering 3～10 hours, preparation doped tin dioxide powder end;

(2) the doped tin dioxide powder end being put into concentration is 0.8～1.2N AgNO ₃In the solution, it is dispersion agent that this solution adds trolamine, and add-on is 10～80ml/kg, prepares silver-colored coating-doping tindioxide powder;

(3) will be set by step (2) silver-colored coating-doping tindioxide powder of obtaining mix with silver powder, mix at 90: 10 by the last weight ratio of silver and doped tin dioxide powder;

(4) with the pressure forming of the mixed powder of step (3) at 150-400MPa, at 750-900 ℃, sintering 2-8hr, preparation electrical contact material.