Ultrafine copper powders with mean diameters of about 0.05 and 1 mu m were prepared by the chemical reduction method, The powders were treated with phosphating solution to improve their oxidation resistance. Nanometer-sized copper powders are unstable in air at room temperature and the treated nanometer-sized powders have an oxidation temperature of about 220 degrees C, which is very stable in air. The treated micrometer-sized copper powders have an oxidation temperature of about 350 degrees C, 100 degrees C higher than that of untreated micrometer-sized copper powder. The phosphating mechanism of copper powders also suggested that insoluble phosphates are deposited on the surface of copper particles and that the surface corrosion of copper powders is carried out by NO3- under acidic conditions. H+ ions were provided by phosphoric acid and dihydrogen orthophosphate in the phosphating solution. (C) 1997 Academic Press. [References: 4]
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机译：采用化学还原法制备了平均粒径约为0.05μm和1μm的超细铜粉，并对它们进行了磷化处理，以提高其抗氧化性能。纳米尺寸的铜粉在室温下在空气中不稳定，并且处理后的纳米尺寸的粉具有约220℃的氧化温度，其在空气中非常稳定。处理后的微米级铜粉的氧化温度为约350℃，比未处理的微米级铜粉的氧化温度高100℃。铜粉的磷化机理还表明，不溶性磷酸盐沉积在铜颗粒的表面上，并且铜粉的表面腐蚀是在酸性条件下通过NO3-进行的。 H +离子是由磷化溶液中的磷酸和正磷酸二氢盐提供的。 （C）1997学术出版社。 [参考：4]
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