姜雁斌
,
官磊
,
莫永达
材料热处理学报
研究了电脉冲连续退火对冷轧时效态AZ91镁合金带材显微组织和力学性能的影响.结果表明:电脉冲退火在较低的温度下快速完成了α-Mg基体的再结晶,可显著细化晶粒.当退火温度为210℃时,α-Mg基体发生完全再结晶,其平均晶粒尺寸由冷轧态的约30μm减小为约7μm,带材的抗拉强度由冷轧态的410 MPa减小至334 MPa,断后伸长率由冷轧态的3.7％增大至23％.电脉冲退火后带材的拉伸断裂方式由冷轧态的脆性沿晶断裂转变为韧性穿晶断裂.电脉冲在其热效应和非热效应的共同作用下快速完成再结晶过程以及β-Mg17Al12相阻碍α-Mg基体晶粒长大,是电脉冲退火细化晶粒的主要原因.
关键词:
镁合金
,
电脉冲退火
,
再结晶
,
力学性能
Rong Hu Tomo Ogura Hiroyasu Tezuka Tatsuo Sato Qing Liu
材料科学技术（英文）
The nucleation and precipitation of Mn-containing dispersoids in an Al-Mg-Si-Mn alloy (6082) have been studied by optical microscopy, EPMA (electron probe microanalysis) and TEM (transmission electron microscopy). The influence of Mn-containing dispersoids on the recrystallization behavior was also investigated. The size and distribution of dispersoids were strongly affected by both the homogenization process and the alloying element distribution formed in the direct chill cast procedure. The Mn-containing dispersoids were observed to nucleate preferentially on the β'-Mg2Si phase and to be aligned along the <100> direction of the matrix. After cold deformation, the morphology of dispersoids greatly influences the recrystallization and grain growth behavior in the annealing process.
关键词:
Mn-containing dispersoids
,
null
,
null
,
null
Yanan Li Yafang Han
材料科学技术（英文）
The recrystallization behavior of Ni3Al base single crystal alloy IC6SX with different mechanical processes has been studied.The specimens of the alloy were treated by surface cleaning and cold working during the blades manufacture, and then heat treated in the temperature range of 800{1260°C for 1 h to 4 h. The microstrcture of the specimens were examined by optical and scaning electron microscopy, and the room temperature tensile property, stress rupture property under the test condition of 1100°C/130 MPa, and the thermal cycle fatigue resistance under 1100−20°C of the specimens with and without recrystallization were carried out. The experimental results showed that the initial recrystallization nucleation temperatures of the alloy by dry grit blasting, wet grit blasting, indentation, shot blasting and burnishing were 900−950°C/1 h, 1000−1100°C/1 h,
1200−1220°C/4 h, 1220−1240°C/1 h and 1220−1240°C/1 h, respectively and the primal recrystallization completing temperatures of the alloy by those mechanical processes mentioned above were 1200−1210°C/1 h, 1100−1200°C/1 h, 1220−1240°C/4 h, 1240−1260°C/1 h and 1240−1260°C/1 h, respectively. The results also indicated that the deformation amount of the specimens by burnishing and dry grit blasting was bigger than that by wet grit blasting and shot blasting according to their recrystallization emperature and the micro-hardness profile below the surface of specimens. It has been found that the recrystallization had no evident effect on mechanical properties of the alloy.
关键词:
Ni3Al
,
single crystal alloy
,
recrystallization
,
surface layer
