A kind of preparation method of ultra-fine single dispersing silver palladium composite powder
Technical field
The present invention relates to noble metal composite powder material, particularly relate to the preparation method of a kind of ultra-fine single dispersing silver palladium composite powder.
Background technology
Silver palladium slurry is with advantages such as its excellent resistance to sintering, weldability, anti-migration ability and moderate costs, it is widely used in hydrid integrated circuit the interconnection conductive strips as circuit and welding zone, and widely applies in the external application components and parts such as chip resistor, MLCC capacitor, chip inductor as electrode etc..In recent years, along with developing rapidly of Aero-Space, mechanics of communication and artificial intelligence technology, requirement to the aspect multi-functional, highly reliable, highly integrated of electronic devices and components is the fiercest, require that the thickness of conducting film is less than below 10um, live width and distance between centers of tracks to circuit require narrower simultaneously, and can normally can work under standing the harsh conditions such as electricity, thermal pulse, this measure more requires that the performance of electronic component is more stable, and resistance to severe rugged environment performance is more preferable.
There is greatest differences in the metal powder of difformity or size application performance in electric slurry, silver palladium composite powder mainly occurs in a form of slurry in the application of electronic devices and components apoplexy due to endogenous wind, and this just requires that the size of powder body is between 0.1 ~ 2.0 μm.And along with scientific and technological progress, it is desirable to silver palladium reaches atom level dispersion, to give full play to the effect of silver palladium powder.Present stage, the domestic research report about palladium-silver alloy powder is less, and the report of industrial-scale production is less.
Summary of the invention
Present invention aims to prior art, it is provided that the preparation method of a kind of ultra-fine single dispersing silver palladium composite powder.
For realizing the object of the invention, the technical solution used in the present invention is as follows:
The preparation method of a kind of ultra-fine single dispersing silver palladium composite powder, it is characterised in that comprise the following steps: silver simple substance, palladium simple substance being put in nitric acid and mixed, after adjustment ph value to 3 ~ 5, adds polyacrylamide, deionized water, adjusting pH value is 10 ~ 12, as material liquid;Hydroxylamine is mixed with deionized water, material liquid is instilled wherein, react 30 ~ 50min, to obtain final product.
Further, described silver simple substance is (10 ~ 12) with palladium simple substance mass ratio: 1.
Further, described polyacrylamide is (0.01 ~ 0.05) with silver simple substance mole ratio: 1.
Further, described reaction 30 ~ 50min is carried out at 15 ~ 24 DEG C.
Polyacrylamide makes the viscosity of silver palladium system increase as non-ionic (polymeric surfactant), utilize hydroxylamine as strong reductant, reduction rate is fast, silver palladium ion reduces under high local concentrations, the pattern of silver palladium powder there occurs significantly conversion, the particle diameter of powder is rendered obvious by ultra-fine trend, substantially 120 ~ 150nm.Simultaneously as polyacrylamide strong reductant effect, silver palladium composite powder monodispersity improves a lot.
The present invention prepares the ultra-fine single dispersing silver palladium composite powder of high-quality by liquid phase, has purity high, and impurity content is low, and particle diameter is in about 120 ~ 150nm, low cost, and easy to operate, technological specification is simple, is suitable to promote the use of.
Detailed description of the invention
Below in conjunction with embodiment, the present invention will be further described.
The preparation method of a kind of ultra-fine single dispersing silver palladium composite powder, it is characterised in that comprise the following steps: silver simple substance, palladium simple substance being put in nitric acid and mixed, after adjustment ph value to 3 ~ 5, adds polyacrylamide, deionized water, adjusting pH value is 10 ~ 12, as material liquid;Hydroxylamine is mixed with deionized water, material liquid is instilled wherein, react 30 ~ 50min, to obtain final product.
Described silver simple substance is (10 ~ 12) with palladium simple substance mass ratio: 1.
Described polyacrylamide is (0.01 ~ 0.05) with silver simple substance mole ratio: 1.
Described reaction 30 ~ 50min is carried out at 15 ~ 24 DEG C.