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本文研究了渗态和高温静态氧化状态下的K-3合金无机盐料浆法制Al-Si涂层中Si的存在形式及其分布。 实验结果表明,Si在渗态涂层中主要以Ni和难熔金属的硅化物((Ni,Cr)_3Si,(Mo,W,Ti)Si_2,Ti_5Si_3]形式存在,并以点状弥散分布在外层β-NiAl相中。其分布深度大约40μm范围内。 高温静态氧化,不但改变了涂层的组织结构,而且还改变了Si在涂层中的存在形式和分布。 在高温氧化后的涂层中,Si的存在形式主要有两种:在涂层的表层,它是以硅酸盐的形式存在;在涂层的内层,主要以固溶状态形式溶解在M_6C碳化物相中,并在涂层与合金基体之间形成连续的含Si的M_6C隔层。

Studies were made of the existing form and the distribution of Si in the Al-Si high temperature coating to K-3 alloy under the state of thermal permeation or static high temperature oxidation. It was found that the Si exists in the coating under the thermal permeation state mainly in the form of silieides, e.g., (Ni, Cr)_3 Si, (Mo,W, Ti)Si_2 and Ti_5Si_3, which dispersively distributes over the 40μm deep zone of the outer β-NiAl phase layer as small particles. While in the coating under static high temperature oxidation, not only its own phase structure but also the existing form and distribution of Si in it are changed. Two chief changed forms of Si are occurred as silicate at the surface and as solid solution in M_6C carbides phase in the interior of the coating. The Si-containing M_6C carbides form a barrier between the coating and the alloy substrate.