Spheroidizing annealing and torsion testing of 0.027 wt% carbon steel rod were conducted to evaluate spheroidization kinetic behavior at 943 K (670 ℃) under deformed and non-deformed states. Kinetic curves were als...Spheroidizing annealing and torsion testing of 0.027 wt% carbon steel rod were conducted to evaluate spheroidization kinetic behavior at 943 K (670 ℃) under deformed and non-deformed states. Kinetic curves were also predicted using the Johnson-Mehl-Avrami-Kolmogorov equation, and the results agree well with the experimental ones. After spheroidization was performed twice, the spherical cementite and precipitated carbides became smaller and the distribution was more uniform. Comparison of materials subjected to single and double spheroidizing annealing indicated a difference in grain size. Torsion performance was considerably improved under double spheroidization, especially the maximum torque with slight variations.展开更多
The spheroidizing mechanism of W-phase in the Mg–Zn–Y–Mn–(B) alloys during solid-solution treatment was investigated by using kinetic methodologies. The microstructure and mechanical properties of heat-treated ...The spheroidizing mechanism of W-phase in the Mg–Zn–Y–Mn–(B) alloys during solid-solution treatment was investigated by using kinetic methodologies. The microstructure and mechanical properties of heat-treated Mg_(94)Zn_(2.5)-Y_(2.5)Mn_1 alloy containing 0.003 wt% B were compared with heat-treated Mg_(94)Zn_(2.5)-Y_(2.5)Mn_1 alloy. The heat-treated Mg_(94)Zn_(2.5)-Y_(2.5)Mn_1 alloy with 0.003 wt% B contained fine and uniform W-phase particles, which exhibited optimal mechanical performance. The ultimate tensile strength, yield strength and elongation were 287.7, 125.5 MPa and 21.1%,respectively.展开更多
基金This work was supported by the National Natural Science Foundation of China (Grant No. 51271035).
文摘Spheroidizing annealing and torsion testing of 0.027 wt% carbon steel rod were conducted to evaluate spheroidization kinetic behavior at 943 K (670 ℃) under deformed and non-deformed states. Kinetic curves were also predicted using the Johnson-Mehl-Avrami-Kolmogorov equation, and the results agree well with the experimental ones. After spheroidization was performed twice, the spherical cementite and precipitated carbides became smaller and the distribution was more uniform. Comparison of materials subjected to single and double spheroidizing annealing indicated a difference in grain size. Torsion performance was considerably improved under double spheroidization, especially the maximum torque with slight variations.
基金support from the National Natural Science Foundation of China(Nos.51474153 and 51574175)Ph.D.Programs Foundation of Ministry of Education of the People’s Republic of China(No.20111402110004)Natural Science Foundation of Shanxi Province(Nos.2009011028-3 and 2012011022-1)
文摘The spheroidizing mechanism of W-phase in the Mg–Zn–Y–Mn–(B) alloys during solid-solution treatment was investigated by using kinetic methodologies. The microstructure and mechanical properties of heat-treated Mg_(94)Zn_(2.5)-Y_(2.5)Mn_1 alloy containing 0.003 wt% B were compared with heat-treated Mg_(94)Zn_(2.5)-Y_(2.5)Mn_1 alloy. The heat-treated Mg_(94)Zn_(2.5)-Y_(2.5)Mn_1 alloy with 0.003 wt% B contained fine and uniform W-phase particles, which exhibited optimal mechanical performance. The ultimate tensile strength, yield strength and elongation were 287.7, 125.5 MPa and 21.1%,respectively.