Abstract. This paper reports an experimental study on the microstructure and corrosion resistance of electro-less Ni-P coatings with increasing content of the rare element cerium (Ce). Surface morphology and the composition of the electro-less Ni-P coatings were studied by scanning electron microscope (SEM), X-ray energy dispersed analysis (EDS) and X-ray diffraction analysis (XRD). Hardness and Adhesive force are researched by a HX-200 Vickers diamond indenter micro-hardness tester. Furthermore, we study the adhesive force by using the Revetest scratch tester. We get the possession of Ce amorphous Ni-P coatings which has excellent properties in anti-corrosion. The effect of the rare element cerium concentration on corrosion resistance of the coatings was evaluated in the groundwater immersion test and porosity test, respectively. The results indicated that added little the rare element cerium into the plating bath increased the phosphorus content of the coatings, decreased the corrosion rates, it also decreases the porosity of the amorphous Ni-P coatings. The lowest corrosion rates of the amorphous Ni-P coatings in groundwater immersion test is 4.1 um·h -1 , at the rare element cerium concentration of 0.12g·L -1.

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In this article, we will discuss the influence of NaCl and anhydrous K 2 CO 3 Pore-forming agent on the porosity properties of Al-Fe absorption materials synthesized by SHS;The research results show that: (1)Under the conditions of the same frequency, with the NaCl and anhydrous K 2 CO 3 volume content increased, the specimen porosity gradually increases, and the absorption coefficient increased linearly ; (2) under the same experiment conditions, using NaCl as Pore-forming agent for Al-Fe absorption materials synthesized by SHS, its sound absorption properties is significantly higher than that using anhydrous K 2 CO 3 as the Pore-forming agent.