Control of Nickel Layer on Metallized Ceramics

The effect of the thickness and chemical composition of the nickel surface on the vacuum density of articles made of VK94 ceramic after soldering with PSr72 solder was studied. It was found that for nickel layer thickness < 3 μm elemental oxides (aluminum, silicon, manganese, molybdenum), which are part of the metallization, are present in its surface. The existing methods of controlling the nickel layer by means of attendant samples do not guarantee surface quality in large batches of articles. A non-destructive method of controlling the thickness of the nickel directly on the articles is proposed. The efficiency of the method makes it possible to check 100% of the articles directly in production. The method is based on measuring the thermo-EMF, which GOST 9.302–88 provides for checking the thickness of galvanic coatings. The method is used at a number of enterprises producing metallized ceramic.