化学镀镍是一项得当将来工业生长要求的一项新技能，它易实现主动化、低污染、低本钱的实用技能，其重要功效是提供耐磨及防腐兼备的防护层。化学镀镍层常应用在以下基体质料上：钢和铁占71%；铝及铝合金上占20%；东西钢及高合金钢上占6%；别的质料上占3%。化学镀镍之以是得到云云遍及的应用，是其优秀的性能所决定的。

化学镀镍的性能长处：

1、镀层的光明度

Compared with the pale yellow nickel plating, most electroless nickel plating layers are silver white, with excellent color change resistance, and the brightness can be connected more permanently. For Ni-P electroless coating, the brightness of the coating increases with the increase of phosphorus content. After adding a certain amount of brightener in the electroless plating solution, the reflectance of the coating can reach more than 80%. Recent studies have shown that electroless nickel copper phosphorus alloy has good brightness and stronger ability to resist discoloration.

2、镀层的硬度

The hardness of the hard chromium plating layer is 960hv. When heated, the hardness drops sharply. The hardness of the electroless nickel plating layer after heat treatment at 400 ℃ for 1H can reach 1100hv, and the hardness of the plating layer is not changed much when the temperature is from room temperature to 400 ℃. Therefore, the electroless nickel plating layer is a heat-resistant coating, which can be used under the condition of friction heat generation, while the hard chromium plating layer can only be used under normal temperature.

3、耐磨性能

For the medium and high phosphorus coatings, after proper heat treatment, the nickel phosphorus alloy coatings have better self-lubricating performance, while the low phosphorus coatings have higher hardness. However, the wear performance tests conducted in the show that the wear resistance of the high phosphorus coatings is higher than that of the low phosphorus alloy coatings. In order to improve the wear resistance of Ni-P coating, w with extremely high hardness was added into Ni-P coating to form ternary alloy coating, and its wear resistance was greatly improved.

4、耐腐蚀性能

Electroless nickel plating is a kind of uniform amorphous layout. It does not have defects such as grain boundaries, dislocations and stacking faults, and the matrix is compact. The corrosion medium is difficult to corrode the matrix metal through the joint interface, and the corrosion resistance is better than that of chromium plating. In addition, electroless nickel plating is almost free from the corrosion of seawater, brine and fresh water. Its corrosion resistance in HCl and sulfuric acid is better than that of stainless steel. It can resist the corrosion of various media, such as high concentration caustic soda, hydrogen sulfide and lactic acid.

5、可焊性

The application of electroless nickel plating in the electronic industry is mainly on discrete devices, which not only requires the coating to have excellent wear resistance, corrosion resistance and electric warfare performance, but also requires the coating to have good solderability. For example, the solderability of the aluminum heat sink in the generator is poor. If a layer of 7-8um electroless nickel plating is coated on the surface of the aluminum base, its solderability can be improved, and the problem of connecting the aluminum heat sink and the transistor can be solved. In addition, electroless nickel plating can also be used for high-energy microwave devices, connectors and submarine communication components. In the same general case, the solderability of electroless nickel plating is measured by the method of acceptance expansion area, i.e. acceptance & phi; Put a 1.5mm solder wire on the surface of the coating, heat it in 400 ℃ and hydrogen nitrogen mixed gas for 30min, and measure the expansion area. The relationship between the solderability and the phosphorus content of the coating can be obtained. The larger the diffusion area, the better the solderability of the coating.

6、二元合金

The most widely used electroless nickel plating is in the valve manufacturing industry. The ball valve made of steel can be improved in corrosion resistance by 12-25um high phosphorus electroless nickel plating, and its service life can be extended by more than one time. Carbon steel solid parts are plated with 25 ~ 50um thick high phosphorus electroless nickel plating, which can replace stainless steel solid parts. The service life of the oil well pump covered by electroless nickel plating is more than 4 years, and the service life of the oil well pump without cover is only 6 months. Zhongyuan Oilfield has electroless phosphorus alloy plating on pipelines, valves, mud pumps and other parts, so that these parts have the ability to resist HS and HCl corrosion and greatly improve their service life.

7、多元合金

The multi-element nickel alloy layer is a nickel based alloy composed of more than three elements, which can improve the performance of the alloy and has good growth potential. The hardness, wear resistance, corrosion resistance, magnetic and thermal properties of the coating can be innovated by elements such as Cu, W, Mo, Sn, Cr, and Co. Multi alloy will be the growth bias of electroless nickel plating.

8、要得到高质量的化学镀镍合金层，工艺技能和利用机理等各方面都很要害，我国的化学镀镍还处于生长阶段。随着常常设置装备部署的高速生长，以后，化学镀镍工业将会有新的进步，并在各行各业中的应用将越发遍及。由二元化学镀镍生长到多元化学镀镍是将来的一定趋向。

本文章出自：www.newstar-china.com