(中南大學 粉末冶金國家重點實驗室，長沙 410083)
摘 要: 分別以316L(40%，體積分數(shù))、316L(60%)為芯、殼層喂料，研究工藝參數(shù)如殼層熔體溫度、殼層注射速度和延遲時間對粉末共注射芯層熔體形貌的影響；分析工藝參數(shù)對金屬共注射芯層形貌影響的流變學機理。結果表明：芯層熔體前沿呈蘑菇狀；固定芯層熔體溫度，隨著殼層熔體溫度的升高，芯層穿透深度從148 mm減小到136 mm，最大穿透寬度從133 mm增加到139 mm；隨殼層注射速度的增加，芯層穿透深度從148 mm減小到143 mm，而芯層穿透寬度的變化規(guī)律不明顯；隨著芯層熔體延遲時間的增大，芯層穿透深度從146 mm增加到154 mm，穿透寬度從118 mm增加到136 mm。
關鍵字: 金屬粉末共注射成形；工藝參數(shù)；芯層熔體形貌；流變學；芯、殼層黏度比
metal powder co-injection molding
（State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:Using two feedstocks, 316L(60%) and 316L(40%), as core and skin feedstocks, the effects of processing parameters, such as skin melt temperature, skin velocity and delay time, on the core melt morphology of metal co-injection molding were studied. The mechanism of the effect of processing parameters on the core melt morphology was studied on the basis of rheological theory. The results show that core melt front shows the shape of mushroom. With the increase of skin melt temperature, the penetration depth decreases from 148 mm to 136 mm, and the largest penetration width increases from 133 mm to 139 mm. While there is no significant variation on the core penetration with the increase of skin velocity, the penetration depth decreases from 148 mm to 143 mm. With the increase of delay time, the core penetration depth and width change significantly from 146 mm to 154 mm and from 118 mm to 136 mm, respectively.
Key words: metal powder co-injection molding; processing parameters; core melt morphology; rheology; core-skin viscosity ratio
