The importance of coating equipment for coating thickness distribution
Vacuum coating electromechanical always want more evenly distributed coating equipment plating thickness on the workpiece, the better the deposition. When the total amount of metal deposited on the workpiece is the same, if the thickness is uneven, it will bring a lot of disadvantages:
(1) For the anodic coating, vacuum coating equipment can not stand at the expense of a thin ...coating of corrosion will first make the matrix rust. And a part of Corroded parts already failed, resulting in a waste of the coating is too thick at the metal. If it is to ensure the thinnest not rust, can only increase the average thickness, resulting in plating cost increases.
(2) to the cathode of the coating, vacuum coating equipment thin coatings at high porosity (see Part 10), it is easy to produce rust spots, and then increase the rust to form contiguous corrosion. Compared with the anodic coatings, cathodic corrosion coating thin place faster. For local seepage nitrogen, carburizing coating, easy to form thin at the hole, lose protection. If the thickness uniformity of the various parts of the porosity is not very different, the overall increase corrosion resistance. For example, the battery bright nickel plated steel rollers, housing (particularly by bottom place) coating is thin, even when washing and drying already starting small rust spots, yellowing, this should "the white" treatment, after rapid drying of water-soluble blocking agent.
(3) For the bright plating, vacuum coating equipment thin coating at the cathode current density due to small, so light leveling poor, affect the overall appearance.
(4) alloy electrodeposition, alloy composition is not the same at different thickness, or the appearance of uneven (such as imitation gold plating), and corrosion resistance are inconsistent or (such as zinc-nickel alloy).
(5) physical coating at different thicknesses, the mechanical properties (such as brittleness, internal stress, etc.) are not the same. If you would have to be plated after stamping molding machine processing, the coating is too thick at the often poor machining performance (peel, crack, powder off, etc.).
Terms of corrosion resistance, or appearance, machining performance perspective, both want to improve the uniformity of the coating thickness of vacuum coating equipment. For the size of the hard chrome plating, if the user requires no plating after grinding treatment, it is difficult to do; sometimes in order to ensure the thinnest reach the final size requirements, thickness uniformity is poor, have greatly increased the average thickness, which is in production are not uncommon. To make each part of the coating thickness on the workpiece as close as possible, we must understand the impact of thickness uniformity factor.
(3) For the bright plating, vacuum coating equipment thin coating at the cathode current density due to small, so light leveling poor, affect the overall appearance.
(4) alloy electrodeposition, alloy composition is not the same at different thickness, or the appearance of uneven (such as imitation gold plating), and corrosion resistance are inconsistent or (such as zinc-nickel alloy).
(5) physical coating at different thicknesses, the mechanical properties (such as brittleness, internal stress, etc.) are not the same. If you would have to be plated after stamping molding machine processing, the coating is too thick at the often poor machining performance (peel, crack, powder off, etc.).
Terms of corrosion resistance, or appearance, machining performance perspective, both want to improve the uniformity of the coating thickness of vacuum coating equipment. For the size of the hard chrome plating, if the user requires no plating after grinding treatment, it is difficult to do; sometimes in order to ensure the thinnest reach the final size requirements, thickness uniformity is poor, have greatly increased the average thickness, which is in production are not uncommon. To make each part of the coating thickness on the workpiece as close as possible, we must understand the impact of thickness uniformity factor.
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