The invention provides a sodium gold sulfide plating solution and an electroplating method thereof, relates to the field of gold plating solutions, and discovers gold plating solution not containing cyanide ions and high in quality to replace a cyanide gold plating process to reduce the harm to environment and operation workers, and meanwhile, the plating solution is stable in physical property, and can meet requirements on transpiration and storage. The invention provides a cyanide-free gold plating solution. The sodium gold sulfide plating solution comprises gold sulfite, a complexing agent,a conductive agent, a current stabilizer and a buffer solution. The sodium gold sulfide plating solution and the electroplating method have the beneficial effects that gold ions in the solution is more stable, and the plating solution storage time is longer; a brightener is added in a composition to enable the surface of the gold plating layer to be finer and more smooth, the gap is reduced, andthe glossiness of the surface of the gold plating layer is higher; a dispersant is added in the composition, so that the plating solution is high in stability and dispersibility, high in uniformity, and high in cathodic current efficiency; and the plating layer is high in welding performance, high in corrosion resistance, and good in binding force.

Sodium gold sulfide plating solution and electroplating method thereof

The invention discloses a cyanide-free 18k gold electrocasting solution and a preparation method and application thereof. The cyanide-free 18k gold electrocasting solution is prepared from the raw materials by volume: 10-12 g/L of gold, 2.2-2.5 g/L of copper, and 0.6-1 g/L of indium. The electrocasting solution is high in stability, high in dispersibility, and high in covering power. The electrocasting solution can be prepared in advance, and therefore labor intensity is lowered, production efficiency is improved, and the quality of ornaments is improved. Toxic substances containing cyanide are not adopted, and therefore security is high. The gold content is easy to control, and therefore gold loss is reduced, and yield is improved. Hardness of a 18k gold ornament is improved, and stability of the ornament during wearing is better guaranteed, and embedded gemstones are prevented from loosing. The corrosion resistance, decoloring resistance and abrasion resistance of the 18k gold ornament are obviously improved.

Cyanide-free 18k gold electrocasting solution and preparation method and application thereof

The invention relates to the technical field of metal corrosion protection and surface treatment, in particular to a cyanide-free alkaline cuprous plating additive. The additive comprises 50-200 partsof complexing agent, 0.1-20 parts of stabilizer, 0.01-0.5 part of brightener, 0.1-5 parts of leveling agent, 10-20 parts of NaOH, 5-20 parts of Na2CO3 and 15-50 parts of cuprous compound. The additive does not contain cyanide and organic phosphonate, is suitable for cyanide-free alkaline copper plating electroplating solution taking cuprous salt as main salt, and effectively solves the problem that traditional cyanide-free alkaline copper plating generates a loose plating layer with poor binding force due to displacement reaction; meanwhile, a certain activation effect can be generated on a steel substrate, a copper coating with good binding force can be obtained on the steel substrate, and the additive is safe, efficient and environmentally friendly.

Cyanide-free alkaline cuprous plating additive

The invention discloses a preparation method of a zirconium alloy material with a chromium coating and application thereof. The preparation method comprises the following steps of degreasing, picklingto remove a surface hardened layer, activating to remove an oxidation film and the like; or adding a nickel transition layer; and finally preparing the chromium coating on the inner and outer surfaces of a zirconium alloy sheet or pipe (particularly used for manufacturing a nuclear reactor fuel cladding pipe with a high length-diameter ratio) by controlling electroplating parameters. The requirement for long-size and large-scale industrial production can be met.

Preparation method of zirconium alloy material with chromium coating and application thereof

The invention provides a trivalent black chromium electroplating solution for a solar heat collector, and relates to the technical field of electroplating. The trivalent black chromium electroplatingsolution per liter comprises 20-60 g of main salt, 150-230 g of conductive salt, 60-100 g of buffer salt, 30-80 g of a complexing agent, 1.5-4 g of cysteine, 0.5-2 g of potassium thiocyanate and 0.2-2g of a wetting agent, wherein the complexing agent consists of citric acid and salicylic acid in a mass ratio of 0.5-1.5:1, and the wetting agent consists of sodium dioctyl sulfosuccinate and polyethylene glycol in a mass ratio of 1-2:1. The trivalent black chromium electroplating solution for the solar heat collector can be used for a heat absorption layer of the solar heat collector, and a plating layer has the characteristics of excellent bonding performance with a substrate, good corrosion resistance and the like.

Trivalent black chromium electroplating solution for solar heat collector

The invention discloses a low-concentration sulfate trivalent chromium quick chromium-plated electroplating solution and a preparation method thereof. The electroplating solution is prepared from a trivalent chromium main salt, a primary complexing agent, an auxiliary complexing agent, conductive salt, a buffer agent, a surfactant and a brightening agent. The preparation method for the electroplating solution comprises the following steps: adding main salt, the primary complexing agent and the auxiliary complexing agent into water, stirring and dissolving, and preserving heat for 2 hours at atemperature being 55-70 DEG C to obtain a solution A; adding the conductive salt and the buffer agent into the solution A, and stirring and dissolving to obtain a solution B; adding the surfactant andthe brightening agent into the solution B, and adding water to a needed volume, thereby obtaining a solution C; and regulating the pH to 2.5-4.0 with sulfuric acid or sodium hydroxide, thereby obtaining the electroplating solution. On the basis of low chromium salt concentration, the electroplating solution still can achieve the effect of high deposition speed being 0.25 mu m/min which is far higher than 0.06 mu m/min of a commercially available decorative sulfate trivalent chromium electroplating solution; and the obtained trivalent chromium coating is bright and uniform, and has good binding force with base materials such as copper and nickel.

Low-concentration sulfate trivalent chromium quick chromium-plated electroplating solution and preparation method thereof

The invention discloses a monovalent gold cyanide-free gold electroplating bath based on alkaloid compound coordination and application thereof. The electroplating bath comprises monovalent gold salt,a coordination agent I, a coordination agent II, a pH buffering agent (used as conducting salt at the same time), a wetting agent and an additive, wherein sodium sulfite containing monovalent gold isused as main salt; sodium sulfite is used as the coordination agent I; alkaloid is used as the coordination agent II; a mixture of dipotassium phosphate, sodium tetraborate, citric acid and potassiumcitrate is used as the pH buffering agent (used as conducting salt at the same time); polyoxy organic matter is used as the wetting agent; and a heterocyclic organic compound is used as the additive.The cyanide-free gold electroplating bath is stable and is still clear and colorless after being placed for a long time, the replacement resistance is high, and the phenomenon of a replaced gold layer is avoided after a fresh nickel plate is arranged in the electroplating bath for 5 min; and the even-plating capacity is good, and under the rated electroplating conditions, an obtained gold coatingis good in bonding force with a substrate and bright and yellow in appearance.

Monovalent gold cyanide-free gold electroplating bath based on alkaloid compound coordination and application thereof

The invention discloses electroplating liquid of a trivalent chromium system for ferrochrome electrodeposition and a preparation method thereof. A solvent of the electroplating liquid is water, and pHis 2.7-4.5. Solutes comprise trivalent chromium main salt, a trivalent chromium main complexing agent, a trivalent chromium auxiliary complexing agent, ferrous main salt, conducting salt, a buffer agent, a stabilizer, a surface active agent and a composite brightening agent. Trivalent chromium is coordinated in a composite coordinating mode, the coordinating capacity of water molecules on the trivalent chromium is lowered, and thus the deposition efficiency of chromium on the surface of a cathode is improved. The specific main complexing agent is micromolecular carboxylic acid and salt of themicromolecular carboxylic acid and can replace the water molecules to be complexed with the trivalent chromium, trivalent chromium electroreduction is promoted, the main complexing agent and the specific auxiliary complexing agent are complexed with trivalent chromium ions jointly to form a combined composite complex, and trivalent chromium electroreduction is further promoted.

Electroplating liquid of trivalent chromium system for ferrochrome electrodeposition and preparation method thereof

The invention discloses a trivalent gold cyanide-free gold plating electroplating solution based on heterocyclic alkaloid coordination and application thereof. The electroplating solution comprises atrivalent gold salt, a coordination agent, a pH buffering agent, a mildew preventive and an additive, wherein taking chloroauric acid which provides trivalent gold as a main salt, and taking heterocyclic alkaloid as a coordination agent, and the mixture of anhydrous potassium carbonate and potassium dihydrogen phosphate is used as a pH buffer agent, sodium tetraborate or sodium benzoate or formaldehyde is used as a mildew preventive, and sulfur-containing organic matters are used as additives. According to trivalent gold cyanide-free gold plating electroplating solution based on heterocyclic alkaloid coordination and application thereof, the cyanide-free gold plating solution is convenient to source and outstanding in comprehensive performance; the plating solution has good plating resistance; the anti-replacement capability is high, and the phenomenon that the gold layer is replaced due to the fact that the fresh nickel plating piece is placed in the plating solution for 3 minutes isavoided; the binding force of the gold plating layer and the nickel and the copper substrate is good under the wide current density of the 0.1-1.2A/dm , the brightness is high, and the color is uniform and golden; in addition, the method has the characteristic that the plating solution is simple to prepare, the gold plating process is convenient and controllable, and the like.

Trivalent gold cyanide-free gold plating electroplating solution based on heterocyclic alkaloid coordination and application thereof

The invention discloses a preparation method of a cysteine aurous acid solid. The cysteine aurous acid solid is prepared from the following raw materials: a trivalent gold material, a reducing agent and cysteine. The trivalent gold material in the raw materials can also be prepared from elemental gold and aqua regia, and gold sodium sulfite or gold potassium sulfite can also be directly used as the gold source in the raw materials. The reducing agent is an organic or inorganic compound with weak reducibility and can selectively reduce the trivalent gold material into a monovalent gold compoundso as to avoid generation of elemental gold. In the preparation method of the cysteine aurous acid solid provided by the invention, cysteine can be stably coordinated with monovalent gold ions. The preparation method is simple, controllable, good in repeatability and short in consumed time.

Yang Fangzu

Papers

Low-concentration sulfate trivalent chromium quick chromium-plated electroplating solution and preparation method thereof

Monovalent gold cyanide-free gold electroplating bath based on alkaloid compound coordination and application thereof

Electroplating liquid of trivalent chromium system for ferrochrome electrodeposition and preparation method thereof

Trivalent gold cyanide-free gold plating electroplating solution based on heterocyclic alkaloid coordination and application thereof

Preparation method of cysteine aurous acid solid