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本文讨论了用湿法冶金方法生产由一种金属或合金涂复在另一种金属或非金属的核心上所组成的复合粉末。评述了这种复合粉末用在热喷涂中的许多优点,主要包括:(1)这种粉末具有非均相性质,由此可能得到各式各样的不一般的材料组合。(2)金属涂层在喷涂时保护核心免受氧化。(3)和混合的粉末相比,由于有优良的金属结合,具有较好的沉积效率。对于与复合粉末应用有关的火焰喷涂和等离子喷涂的特殊性能简单地加以综述。讨论了热喷涂中因发挥了复合粉末的特殊性能而得到益处的各个领域。这些包括:(1)使用 Ni/Al 的结合涂层。(2)使用 Ni/石墨和 NiCr/硅藻土作涡轮中的可磨损的密封件。(3)使用 Co/WC,Ni/WTiC_2和 NiCr/Cr_3C_2作抗磨损涂层。(4)使用 Ni/CaF_2和 NiO/CaF_2作低磨擦密封件。报导的数据包括:沉积效率、氧化损失、结合强度、涂层硬度、可磨损性以及磨擦和磨损结果。
This paper discusses the use of hydrometallurgical methods to produce composite powders consisting of one metal or alloy coated onto another metal or non-metal core. The advantages of using this composite powder in thermal spraying are reviewed, including: (1) The powder has a heterogeneous nature, whereby a wide variety of unusual material combinations are possible. (2) The metal coating protects the core from oxidation during spraying. (3) Compared with the mixed powder, it has better deposition efficiency due to excellent metal bonding. The special properties of flame spraying and plasma spraying related to composite powder applications are briefly reviewed. The fields of thermal spraying that benefit from the special properties of composite powders are discussed. These include: (1) Ni / Al bonded coatings. (2) Use of Ni / graphite and NiCr / diatomaceous earth as abradable seals in turbines. (3) Use Co / WC, Ni / WTiC_2 and NiCr / Cr_3C_2 as anti-wear coatings. (4) Use Ni / CaF_2 and NiO / CaF_2 as low friction seals. The reported data includes: deposition efficiency, oxidation loss, bond strength, coating hardness, abrasion and friction and wear results.