Summary of the invention
The objective of the invention is at the deficiencies in the prior art, a kind of SiC ceramic grain surface electroless copper plating method is provided, simple, cheap, the ceramic grain surface copper coating that makes coats evenly.
For realizing such purpose, technical scheme of the present invention is: at first the SiC ceramic grain surface is carried out the nitric acid roughening treatment, with tungsten powder, hydrogen peroxide, dehydrated alcohol and glacial acetic acid prepare colloidal sol, then the SiC ceramic particle after the roughening treatment is steeped among the colloidal sol and be aided with sonic oscillation, make at ceramic grain surface and form colloidal sol thin layer, drying and hydrogen reducing, after obtaining the SiC ceramic particle of plating tungsten, carry out electroless copper again and handle.Because copper is wrapped up in uniform pottery to the good wettability of tungsten and the catalytic activity of tungsten self thereby can obtain copper-clad.
Method of the present invention specifically comprises the steps:
1) the SiC ceramic particle is put into concentration greater than 70% nitric acid and sonic oscillation in addition, it is carried out roughening treatment, take out after 5 minutes and use deionized water rinsing, obtain having and clean and the SiC ceramic particle of uneven surface.
2) by following proportioning and method preparation colloidal sol: get every 0.5-1 gram tungsten powder and the reaction of 2.5-5 milliliter hydrogen peroxide, reaction adds 2 milliliters of dehydrated alcohols afterwards and 0.75 milliliter of acetate mixes, and filters out reaction residual, obtains faint yellow colloidal sol.The amount of the colloidal sol of preparing wants to satisfy the needs of the complete submergence SiC of next step ceramic particle.
3) being immersed in the above-mentioned colloidal sol, be aided with sonic oscillation 10-20 minute, make SiC ceramic particle homodisperse in colloidal sol through the SiC of roughening treatment ceramic particle;
4) the SiC ceramic particle after the above processing is put into 300-350 ℃ the dry 2-3 of loft drier hour, take out cooling;
5) the good SiC ceramic particle of above drying under hydrogen atmosphere in 760-800 ℃ of reductase 12-3 hour, take out behind the furnace cooling, obtain the SiC ceramic particle of plating tungsten.
6) the preparation plating bath contains the copper sulfate of 15g/l, the formaldehyde of 25ml/l, the EDTA disodium of 25g/l, the Seignette salt of 14g/l and the yellow prussiate of potash of 10mg/l in the plating bath, and the pH value is adjusted between the 12-13 with NaOH solution, 60 ℃ of temperature.The SiC ceramic particle of above-mentioned plating tungsten is poured in the plating bath, and loading capacity is 10-18g/l.Be aided with magnetic agitation.
7) react completely after-filtration and at 120-160 ℃ of dry 3-5 hour obtains copper-clad and wraps up in uniform SiC ceramic particle.
The present invention has easy handling, coats evenly advantage with low cost.As long as the amount of required colloidal sol can be soaked the SiC ceramic particle fully in the method, need not simultaneously with expensive PdCl
2Perhaps AgCl activates ceramic surface, has omitted the sensitization step.Because copper to the good wettability of tungsten and the catalytic activity of tungsten self, can obtain the copper facing SiC ceramic particle of even adhere firmly of thickness and bright in color.The thickness of plating tungsten layer can be controlled at below the 50-200nm, and the thickness of copper coating is below 2 μ m.In the preparation of metal-base composites and stupalith, have wide practical use.This technology of the present invention goes for other as Al
2O
3, the electroless copper of materials such as graphite.
Embodiment
Below by specific embodiment technical scheme of the present invention is further described.Following examples are that the SiC ceramic particle of 20 μ m is that example describes with median size, but should not be considered as limitation of the invention.
Embodiment 1:
1. 5g SiC ceramic particle is put into 20ml concentration and be 70% nitric acid and sonic oscillation in addition, it is carried out roughening treatment.Take out after 5 minutes and use deionized water rinsing, obtain having and clean and the SiC ceramic particle of uneven surface.
2. get the reaction of 1g tungsten powder and 5ml hydrogen peroxide, reaction adds the 2ml dehydrated alcohol afterwards and 0.75ml acetate mixes.Filter out reaction residual, obtain faint yellow colloidal sol.
3. steeping in the above-mentioned colloidal sol, be aided with sonic oscillation 10 minutes, make SiC ceramic particle homodisperse in colloidal sol through the 5gSiC of roughening treatment ceramic particle.
4. the SiC ceramic particle after the above processing is put into 300 ℃ dry 3 hours of loft drier, taken out cooling.
The good SiC ceramic particle of above drying under hydrogen atmosphere in 760 ℃ of reduction 3 hours, take out behind the furnace cooling, obtain the SiC ceramic particle of plating tungsten.
6. press 7.5g copper sulfate+12.5ml formaldehyde+12.5g EDTA disodium+7g Seignette salt+5mg yellow prussiate of potash configuration plating bath 500ml, the pH value is adjusted between the 12-13 with NaOH solution, 60 ℃ of temperature.The surface is wrapped up the powder of W layer and pour in the plating bath, loading capacity is 10g/l.Be aided with magnetic agitation.
7. react completely after-filtration and 120 ℃ of dryings 5 hours promptly obtains copper-clad and wraps up in uniform SiC ceramic particle.
Embodiment 2:
1. 7g SiC ceramic particle is put into 20ml concentration and be 80% nitric acid and sonic oscillation in addition, it is carried out roughening treatment.Take out after 5 minutes and use deionized water rinsing, obtain having and clean and the SiC ceramic particle of uneven surface.
2. get the reaction of 2g tungsten powder and 5ml hydrogen peroxide, reaction adds the 4ml dehydrated alcohol afterwards and 1.5ml acetate mixes.Filter out reaction residual, obtain faint yellow colloidal sol.
3. steeping in the above-mentioned colloidal sol, be aided with sonic oscillation 15 minutes, make SiC ceramic particle homodisperse in colloidal sol through the 7g of roughening treatment SiC ceramic particle.
4. the SiC ceramic particle after the above processing is put into 320 ℃ dry 2.5 hours of loft drier, taken out cooling.
The good SiC ceramic particle of above drying under hydrogen atmosphere in 780 ℃ of reductase 12 .5 hours, take out behind the furnace cooling, obtain the SiC ceramic particle of plating tungsten.
6. press 7.5g copper sulfate+12.5ml formaldehyde+12.5g EDTA disodium+7g Seignette salt+5mg yellow prussiate of potash configuration plating bath 500ml, the pH value is adjusted between the 12-13 with NaOH solution, 60 ℃ of temperature.The surface is wrapped up the powder of W layer and pour in the plating bath, loading capacity is 14g/l.Be aided with magnetic agitation.
7. react completely after-filtration and 140 ℃ of dryings 4 hours promptly obtains copper-clad and wraps up in uniform SiC ceramic particle.
Embodiment 3:
1. 9g SiC ceramic particle is put into 20ml concentration and be 90% nitric acid and sonic oscillation in addition, it is carried out roughening treatment.Take out after 5 minutes and use deionized water rinsing, obtain having and clean and the SiC ceramic particle of uneven surface.
2. get the reaction of 4g tungsten powder and 40ml hydrogen peroxide, reaction adds the 16ml dehydrated alcohol afterwards and 3ml acetate mixes.Filter out reaction residual, obtain faint yellow colloidal sol.
3. steeping in the above-mentioned colloidal sol, be aided with sonic oscillation 20 minutes, make SiC ceramic particle homodisperse in colloidal sol through the 9gSiC of roughening treatment ceramic particle.
4. the SiC ceramic particle after the above processing is put into 350 ℃ dry 2 hours of loft drier, taken out cooling.
The good SiC ceramic particle of above drying under hydrogen atmosphere in 800 ℃ of reductase 12s hour, take out behind the furnace cooling, obtain the SiC ceramic particle of plating tungsten.
6. press 7.5g copper sulfate+12.5ml formaldehyde+12.5g EDTA disodium+7g Seignette salt+5mg yellow prussiate of potash configuration plating bath 500ml, the pH value is adjusted between the 12-13 with NaOH solution, 60 ℃ of temperature.The surface is wrapped up the powder of W layer and pour in the plating bath, loading capacity is 18g/l.Be aided with magnetic agitation.
7. react completely after-filtration and 160 ℃ of dryings 3 hours promptly obtains copper-clad and wraps up in uniform SiC ceramic particle.