Solution concentration algorithm in PCB circuit board manufacturing

In the printed circuit board manufacturing technology, various solutions account for a large proportion, and these solutions play a very critical role in the quality of the final product of the printed circuit board. Whether it is self-matching or purchase, scientific calculations are essential. Here we provide six calculation methods for peers to choose.　　1, weight percent concentration calculation 　　(1) definition: expressed as the weight of the solute as a percentage of the weight of the solution.　　(2) Example: Try to find the weight percentage concentration of the solute obtained by dissolving 3 grams of sodium carbonate in 100 grams of water? 　　2, molar concentration calculation 　　? Definition: The number of moles of solute containing 1 gram of solute in one liter. Symbols: M and n represent the moles of solute, and V represents the volume of the solution.　　 Such as: a solution containing 1 mol of solute in 1 liter has a molar concentration of 1M; a concentration of 1/10 mol is 0.1M, and so on. Example: Dissolve 100 grams of sodium hydroxide in water and prepare a 500 ml solution. What is the molar concentration of this solution? Solution: First find the molar number of sodium hydroxide: 　　3, volume ratio concentration calculation: 　　 definition: Refers to the ratio of the volume of the solute (or concentrated solution) to the volume of the solvent.　　 Example: 1:5 sulfuric acid solution is made up of one volume of concentrated sulfuric acid and five volumes of water.　　4, gram concentration calculation: 　　 definition: the number of grams of solute contained in one liter of solution.　　 Example: 100 grams of copper sulfate dissolved in 10 liters of aqueous solution, ask what is the concentration of one liter? 　　100/10u003d10g/liter　　5, specific gravity calculation 　　 definition: the weight per unit volume of an object (unit: g/cm3).　　Measurement method: hydrometer.　　In the electroplating process, it involves the calculation of parameters such as the thickness of the electroplating, the electroplating time, the current density, and the calculation of the current efficiency. Of course, the calculation of the plating area is also very important, to ensure the uniformity and consistency of the plating on the surface of the printed circuit board and the hole, and to calculate the plated area more accurately. The area integrator currently used (calculates the area of u200bu200bthe negative film) and the development of computer calculation software make the surface of the printed circuit board and the area of u200bu200bthe hole more accurate. However, sometimes manual calculation methods are used, and the following formulas can be used. 1. Calculation formula of plating thickness: (thickness code: d, unit: micron) du003d(C×Dk×t×ηk)/60r　　 2. Plating time calculation formula: (time code: t, unit: minutes) tu003d (60×r×d)/(C×Dk×ηk)　　 u200bu200b3. Calculation formula of cathode current density: (code:, unit: ampere/decimeter 2) ηku003d(60×r×d)/(C×t× Dk)　　4. The cathode current is calculated by the efficiency formula: Dku003d(60×r×d)/(C×t×Dk)　　 6. The definition of equivalent concentration calculation: the number of gram equivalents of solute contained in one liter of solution. Symbol: N (gram equivalent/liter). The meaning of 　　 equivalent: valence: reflecting the internal connection of element equivalents, the number of lost electrons or the common number of electrons obtained by mutual combination. This is a natural law. Such as valence, atomic weight and element equivalent constitute a phase relationship. Elementu003datomic weight/valence example: “sodium equivalentu003d23/1u003d23; iron equivalentu003d55.9/3u003d18.6” acid, alkali, salt equivalent calculation method: “A” acid equivalentu003dacid molecular weight/metal in acid molecule The number of replaced hydrogen atoms B 　 the equivalent of alkali u003d the molecular weight of the alkali / the number of hydroxide radicals contained in the alkali molecule C 　 the equivalent of salt u003d the molecular weight of the salt / the number of metal atoms in the salt molecule and the metal valence