(中南大學 粉末冶金國家重點實驗室，長沙 410083)
摘 要: 基于加壓燒結(jié)粘彈性流動理論，引入燒結(jié)速率不匹配造成的界面應(yīng)力，并考慮界面應(yīng)力分布情況，建立兩種材料共燒結(jié)致密化模型，描述共燒結(jié)界面應(yīng)力對共燒結(jié)致密化的影響。通過兩種材料自由燒結(jié)數(shù)據(jù)，進行材料參數(shù)擬合；通過擬合得到的材料參數(shù)進行共燒結(jié)致密化模型模擬。結(jié)果表明：共燒結(jié)會使得試樣中存在密度梯度，并且可能加大或者縮小界面處密度差異，對共燒結(jié)后界面結(jié)合強度造成影響。采用不同孔隙率的銅粉共燒結(jié)進行驗證，實驗測得共燒結(jié)試樣密度梯度分布以及界面處密度差異變化和模型預(yù)測結(jié)果一致。
關(guān)鍵字: 共燒結(jié)；致密化；燒結(jié)理論；密度梯度
（State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:A model based on viscoelastic theory was established on co-sintering densification. The interface stress caused by mismatch densification rates was modeled and calculated. The interface stress distribution was considered in the model. The model was simulated with the parameters fitted by free sintering of different materials. The results show that the density gradient in co-sintering samples is caused by interface stress, the density difference at co-sintering interface may be enlarged or minimized, and thus has different effects on interface bonding strength. The experimental verification was conducted by using copper powder with different powder loadings. The density gradients and density discrepancy at interface measured in the experiment agree well with the model predictions.
Key words: co-sintering; densification; sintering theory; density gradient
