1 Test Materials and Methods 20 mm X 1.5 mm plate specimens. For electroless plating iP, the main components of the plating solution are nickel sulfate and sodium hypophosphite, and then a suitable amount of a stabilizer buffer and a wetting agent. For electroless plating, in addition to the above components, sodium tungstate must also be added to the bath. The matrix sample is first processed, and its main process flow is sandpaper polishing, chemical degreasing and rust cleaning and pickling acid activation. Chemical deposition can be performed after pretreatment, electroless plating during deposition, temperature control of the forging solution at 85+3, barrel value of only 4.85, electroless plating, temperature control of the plating solution at 90, values ​​of 8.8, and 9.0. The sample to be plated was put into a clamped resistance furnace and heat-treated at 200, 400, 600, respectively. The holding time was 1.52. The test results were tested on a four-mode father beam diffractometer for the samples that had been heat-treated at different temperatures. . Wavelength 1.54178, scanning mode continuous spectrum, drive axis 3 23, start angle 25, such as 8, end angle 105, such as 8, scan speed 3 = 0.2 claw 1. Results 18. Electroless plating and alloy plating have attracted attention from the industrial sector due to their excellent corrosion resistance, wear-resistant coating thickness, and other characteristics. However, with the development of science and technology, various industrial sectors put forward higher requirements for materials, especially corrosion resistance and wear resistance at high temperatures. The alloy layer often fails to meet the requirements of alloying methods to achieve Jia elements and electroless plating. Co-deposition, the resulting alloy has good thermal stability, and has good high temperature corrosion resistance and wear resistance. For these two kinds of alloy coatings, research at home and abroad tends to emphasize the variation of the properties of the process and plating properties and hardness, and there are few reports at home and abroad. Chemical plating, and the structure and properties of the guilty alloys Luoyang Institute of Materials Engineering Luoyang 4739, Tang Rui Jiang Bingyuan Abstract: The structure and heat treatment of the state and the alloy after the heat treatment of the structure of the erosion and hardness; analysis and discussion of the heat treatment temperature and The effect of the elements on the structure and properties of the alloy. 3.1 plating structure and heat treatment after the coating structure has a skull-shaped scattering peaks. This is a typical characteristic of amorphous gold, ruler, and 0. This shows that both alloys are non-attributed alloys when plated. In addition, it can also be seen that the scattering peak of the stellite is not completely amorphous than the gold grading. This is due to the fact that the amount of phosphorus in the alloy is greater than the amount of phosphorus contained in the alloy. 8. The increase in phosphorus content can increase the long-range disorder of the alloy's atomic arrangement. Therefore, the cadaveric gold-containing amorphous state is more complete, showing its features. The father only has a skull-shaped scattering peak. Compared to the plated state, its height slightly increases slightly. Explain that the alloy is still amorphous. Only slight structural relaxation occurred. The amorphous state does not change the structural relaxation. The head-like scattering peaks disappeared, and diffraction peaks appeared. These peaks were found to correspond to the amount of supersaturated solid solution desolventized. You can also see. There are many diffraction peaks in 3, and the peak is high. It shows that the gold-containing alloy has completely crystallized and becomes a crystalline alloy layer, while the diffraction peak in 7 is very small. And the peak value is low, indicating that the jagged sub-alloy has just started to crystallize. Only the mixed crystal alloy 2.1 corrosion test will immerse all the samples that have been heat-treated in the plating state and at different temperatures in the holder 30. The etching time is the removal of the sample. After drying, the lost weight was measured with a photoelectric analysis balance. The unit is mgCm,h, result 9. 2.2 Hardness Test The microhardness values ​​of the as-plated and heat-treated samples at different temperatures were determined using a 71-type microhardness tester. The load was 2006 and the holding time was 153. Results 1 3 Analysis and discussion. Therefore, the addition of the elements will increase the thermal stability of the alloy layer and increase the crystallization transition temperature of the amorphous alloy coating. Change. A new phase appeared in his alloy. After that, it is actually rated 0. 3.2 The corrosion resistance is due to their amorphous structure at this time. Amorphous alloys are homogeneous single-phase systems. There are no crystal defects such as grain boundary subgrain boundary dislocations. Therefore, its corrosion resistance is very good. It can also be seen that the corrosion rate of the NiWP alloy is higher than that of the + alloy. This is due to the lower phosphorus content of the alloy. Its degree of amorphous state is not as good as that of the alloy. In addition. The higher the phosphorus content of the plating. The more the positive potential of the entire plating potential and the improvement of the corrosion resistance, the more the corrosion resistance of the mussels alloy is inferior to that of the alloy. After 200, the corrosion resistance of the alloys was slightly improved because of the structural relaxation of the amorphous alloy and the removal of hydrogen remaining in the alloy coating. The internal stress 6 of the plating is reduced, so that the corrosion rate is slightly reduced. After 400, after heat treatment, the two kinds of alloys have undergone different degrees of crystallization transition, and crystal defects such as grain boundary phase boundaries have begun to appear in the coating. At the same time, due to the suppression of ten precipitates, the phosphorus content in the coating matrix phase decreases. The plating potential is negatively shifted and the corrosion resistance is reduced. In addition, he smashed out. Changes in the crystal lattice size of the gold-containing plating cause stress concentration. This reduces the corrosion resistance of the alloy. At this time, the corrosion resistance of the state alloys decreased greatly, and the corrosion resistance of the alloys of the stomach 4 decreased less. From the foregoing discussion, it can be seen that this is due to the fact that the alloy has been fully crystallized at this time, and the critics alloy has improved its thermal stability due to the presence of the boundary elements, and the crystallization is not complete, but only a mixed crystal state, and its crystal defects Component segregation and stress concentration are less than that of red gold. Therefore, at this time, the corrosion resistance of the alloy is already higher than that of the alloy +, and after the 6000 heat treatment, the corrosion resistance of the coating is increased. This is due to the coarsening of grain aggregation in the coating, the grain boundary area decreases 1 while the alloy forms a dense passivation film 171 when annealed in air. 3.3 Microhardness is higher than NiP alloy. This is due to the strengthening effect of W, which is the element with the highest melting point. It shows that the interatomic binding force is very strong. It is co-deposited with the coordinator, which enhances the bond strength between atoms and improves the resistance to local plastic deformation. After 200 heat treatment, the microhardness of the two alloys slightly increased, and it can be considered that some form of structural relaxation or atomic rearrangement resulted from the increase in heat treatment temperature. The phosphorus atoms in the alloy coating diffuse. Phosphorus atoms are randomly deposited on a specific crystal surface of nickel, and the local stress field causes severe lattice distortion. When the phosphorus atoms diffuse to a certain extent, they will precipitate a high hardness dispersion and coherent phase 3. This makes the alloy coating strengthened. However, the gold coating is considered to be finer because of the heated tissue under temperature. Therefore, after the deduction, hot stove after treatment. Its microhardness is still higher than his alloy. After 6000 heat treatment. Inappropriate aggregation occurs. The coherent relationship is destroyed, the coating softens, and the dispersion of the coating alloy decreases by 1. This reduces the microhardness of the alloy coating. at this time. Although the axe gold has completely softened, but due to the dispersion of fine 00 phase precipitation. Strengthen it. It can offset the decrease of some microhardness. Therefore, its microhardness is still higher than that of + alloys. 4 Conclusions Electroless plating and other gold alloys in the world are amorphous in the plated state. Structural relaxation occurred after 200 heat treatments. After 400 heat treatment, the NiP alloy has completely crystallized, while the NoWP gold-containing crystallization is incomplete. After 600, the two kinds of alloys were completely oxidized. The heat treatment temperature has a great influence on the corrosion resistance of the coating. After the heat treatment in 2001, the corrosion resistance of the coating slightly improved. After 400 heat treatment. Plating corrosion resistance decreased. And his alloy coating has a reduced turbidity resistance. The degree is greater. At this time, its corrosion resistance is lower than that of Can alloy. After 600 heat treatment, the corrosion resistance of the coating is improved. His gold hardness is higher than his gold. Both are at 400. However, for the workpieces with required corrosion resistance and wear resistance, from room temperature to 200, the coconuts can be coated with barium alloys in consideration of economy. At temperatures of around 400 or higher, the continent can be selected for gold plating 3 Wong Sheng Tao. Structure and structure analysis of amorphous materials. Beijing: Science Press. 1987. 4 He Shengsheng, from pears. Amorphous materials and their applications, 1987, 10, 6, 26 5 Zou Longfei, Lin Dongliang. Chinese Journal of Corrosion and Protection, 1988, 842816 Wang Xueying, Wang Xi. Material Protection, 1992, 255, 22
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