Microstructural evolution in Al-Zn eutectoid alloy by hot-rolling  

热轧Al-Zn共析合金的显微组织演变(英文)

作　　者：Toshiaki MANAKA Goroh ITOH Yoshinobu MOTOHASHI Takaaki SAKUMA 

机构地区：[1]School of Science and Engineering, Ibaraki University [2]College of Engineering, Ibaraki University

出　　处：《Transactions of Nonferrous Metals Society of China》2014年第7期2107-2111,共5页中国有色金属学报（英文版）

摘　　要：The Al-Zn eutectoid alloy has been widely known as a typical superplastic metallic material, where fine-grained microstructure is usually obtained by heat treatment. Recently, thermo-mechanical controlled process has also been reported to provide a fine-grained microstructure. In the present study, Al-Zn alloy ingots of 20 mm in thickness were homogenized and hot-rolled to a thickness of 2 mm under three processes： 1） the specimen was air-cooled after homogenization and hot-rolled; 2） the specimen was water-quenched after homogenization and hot-rolled; 3） the specimen was immediately hot-rolled after homogenization. Microstructural observation showed that, in processes l and 3, lamellar microstructure was formed after homogenization, and became fragmented to fine-grained microstructure as the hot roiling process proceeded. In process 2, fine-grained microstructure without lamellar microstructure was attained throughout the hot-rolling process. A minimum grain size of 1.6 μm was obtained in process 3. Tensile tests at room temperature showed that the elongation to failure was the largest in process 3.Al-Zn共析合金是一种典型的超塑性金属材料,其细小晶粒组织一般通过热处理获得。近来,热力学控制过程已经运用于微观组织细化。据此,将20 mm厚的铸锭分别按以下3种方案进行均匀化,并热轧至2 mm厚以获得细化微观组织。这3种方案分别为:1)均匀化后空冷和热轧;2)均匀化后水淬和热轧;3)均匀化后立即热轧。微观组织观察表明:采用方案1和3均匀化后形成片层组织,并且在热轧进行的时候破碎成细小的晶粒组织。采用方案2处理时,细小的晶粒组织直接通过热轧过程获得,中间没有形成层片组织。结果表明,采用方案3处理后获得的材料晶粒最小,其尺寸为1.6μm;室温下拉伸测试结果表明,采用方案3处理的材料的伸长率最大。

关 键 词：aluminum-zinc alloy eutectoid microstructure control HOT-ROLLING superplastic material 

分 类 号：TG146.21[一般工业技术—材料科学与工程]