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早在一九二九年,瓦西克(Vacek)已经阐明加入少量的Ni能降低W粉坯块的烧结温度。现在已提出了解释这一作用的一些机构。然而,由于对引入的假设有争议,因此还没有一种解释能被普遍接受为正确的模型。他们都未能对压坯在烧结初始阶段产生显著致密化时,Ni可能起的作用做出具体的解释。人们一直认为,烧结性能可能取决于加Ni的方式,即意味着Ni在初始阶段的作用在烧结机构中是重要的。而Ni的初始状态,即Ni的初始分布和粒度也是重要的,因为添加物的物理状态明显的与将其加入W粉所采用的方法有关。例如,W粉的颗粒与Ni的颗粒相比很小的
As early as 1929, Vacek has shown that adding a small amount of Ni reduces the sintering temperature of the W powder compact. A number of institutions have been proposed to explain this role. However, as there is controversy over the assumptions introduced, there is no single model that can be generally accepted as correct. None of them has any specific explanation for the possible role of Ni in the compact during its initial densification. It has been believed that the sintering behavior may depend on the addition of Ni, meaning that the role of Ni in the initial stage is important in sintering mechanisms. The initial state of Ni, ie, the initial distribution and particle size of Ni, is also important because the physical state of the additive is clearly related to the method used to add it to W powder. For example, the particles of the W powder are small compared to the particles of Ni