(1. 河南科技大學 材料科學與工程學院，洛陽 471003;
2. 河南科技大學 河南省有色金屬材料科學與加工技術重點實驗室，洛陽 471003)
摘 要: 在Gleeble−1500D熱模擬機上對Al2O3/Cu-WC復合材料進行熱壓縮實驗，研究變形溫度為350~750 ℃、應變速率為0.01~5 s−1條件下的熱變形行為。結果表明：Al2O3/Cu-WC復合材料高溫流變應力-應變曲線主要以動態(tài)再結晶軟化機制為特征，峰值應力隨變形溫度的降低或應變速率的升高而增加；熱變形過程中的穩(wěn)態(tài)流變應力可用雙曲正弦本構關系式來描述，其激活能為229.17 kJ/mol。根據(jù)材料動態(tài)模型，計算并建立Al2O3/Cu-WC復合材料的熱加工圖，據(jù)此確定熱變形流變失穩(wěn)區(qū)及熱變形過程的最佳工藝參數(shù)，其熱加工溫度為650~750 ℃，應變速率為0.1~1 s−1。
關鍵字: Al2O3/Cu-WC復合材料；熱變形；流變應力方程；熱加工圖
（1. School of Materials Science and Engineering, Henan University of Science and Technology, Luoyang 471003, China;
2. Henan Key Laboratory of Advanced Non-ferrous Metals, Henan University of Science and Technology,
Luoyang 471003, China）
Abstract:The hot deformation behavior of A2O3/Cu-WC composites was investigated by compression tests on Gleeble−1500D thermal simulator. The tests were performed in the temperature range of 350−750 ℃ and strain rates of 0.01−5 s−1. The results show that A2O3/Cu-WC composite has the typical feature of the softening mechanism of dynamic recovery and dynamic recrystallization. The peak stress increases with decreasing the deformation temperature or increasing the strain rate. The flow behavior is described by the hyperbolic sine constitutive equation, and the activation energy of the composite is about 229.17 kJ/mol. The processing map was calculated and analyzed according to the dynamic materials model. The process of hot deformation in the temperature range and different strain rate can be attained by the map, of which the optimum hot deformation temperature ranges in 650−750 ℃ and strain rate ranges in 0.1−1 s−1, and the instability zones of flow behavior can also be recognized by the processing map.
Key words: A2O3/Cu-WC composite; hot deformation; flow stress equation; processing map
