(北京工業(yè)大學 材料科學與工程學院
新型功能材料教育部重點實驗室， 北京 100022)
摘 要: 研究了單質(zhì)導電材料在放電等離子燒結(jié)(SPS)過程中頸部形成的機理。 以純銅粉末為例， 研究不同燒結(jié)階段的顯微組織特征， 并建立描述頸部形成機理的兩顆粒模型， 計算從顆粒幾何中心到兩顆粒接觸點的溫度分布。 結(jié)果表明， 顆粒內(nèi)的溫度分布極不均勻， 頸部區(qū)域的溫度可以達到材料的熔點甚至沸點。 因此， SPS過程中頸部形成的根本原因是瞬時局部高溫造成顆粒接觸部位的熔化甚至汽化， 形成粘結(jié)。
關(guān)鍵字: 放電等離子燒結(jié)(SPS)； 頸部形成； 溫度分布
（Key Laboratory of New Functional Materials of Education Ministry of China, College of Materials Science and Engineering, Beijing University of Technology, Beijing 100022, China）
Abstract: The mechanism of neck formation of conductive pure materials during SPS was studied. By using the pure copper powders as the sintering material, the microstructure characteristics of different sintering stages were studied and discussed. A two-particle model was developed to describe the temperature distribution from the center to the contact area of two particles. It is concluded from the present model that, there is a greatly inhomogeneous distribution of the temperature in the particle, the temperature is higher than the melting point even boiling point of the material in neck zone. Consequently, the essence of the neck formation is the melting and even vaporizing of the contacting area between particles due to the local extra high temperature.
Key words: spark plasma sintering(SPS); neck formation; temperature distribution
