Inconel 718 superalloys deposited by laser solid forming (LSF) were heat treated with solution treatment,intermediate heat treatment (IHT) and two-stage aging treatment in sequence (SITA heat treatment).The effect of IHT temperature on microstructure,tensile property and notch sensitivity of LSFed Inconel 718 superalloy at 500 ℃ were investigated.As-deposited columnar grains have transformed to equiaxed grains and the grains were refined due to the recrystallization during the SITA heat treatment.It is found that the size and amount ofδ phase dispersed at grain boundaries decreased with the increasing of IHT temperature,and δ phase disappeared when the IHT temperature reached 1 020 ℃.The ultimate tensile strength (UTS) and yield strength (YS) of smooth samples increased to a maximum when the IHT temperature reached 980 ℃ and then decreased slightly to a minimum when the IHT temperature was 1 000 ℃,and followed by slight increasing again till the IHT temperature reached 1 020 ℃,resulted from the competition of precipitation strengthening effect of γ” and γ'phase and the grain boundary weakening effect caused by the gradual disappearance of δ phase with increasing the IHT temperature.The notch sensitivity factor (qe) decreased but still greater than 1 as the IHT temperature increased,which is attributed to the decrease of the size and amount of δ precipitation.
参考文献
| [1] | H.Yuan;W.C.Liu .Effect of the δ phase on the hot deformation behavior of Inconel 718[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2005(1/2):281-289. |
| [2] | Weiju Ren;Theodore Nicholas .Notch size effects on high cycle fatigue limit stress of Udimet 720[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2003(1/2):141-152. |
| [3] | Chu, ZK;Yu, JJ;Sun, XF;Guan, HR;Hu, ZQ .High cycle fatigue behavior of a directionally solidified Ni-base superalloy DZ951[J].Materials Science and Engineering. A, Structural Materials: Properties, Microstructure and Processing,2008(1/2):355-361. |
| [4] | 黄卫东,李延民,冯莉萍,陈静,杨海欧,林鑫.金属材料激光立体成形技术[J].材料工程,2002(03):40-43,27. |
| [5] | 林鑫,杨海欧,陈静,黄卫东.激光快速成形过程中316L不锈钢显微组织的演变[J].金属学报,2006(04):361-368. |
| [6] | Zhao XM;Chen J;Lin X;Huang WD .Study on microstructure and mechanical properties of laser rapid forming Inconel 718[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2008(1/2):119-124. |
| [7] | Yue Ma;Jiahua Sun;Xishan Xie .An investigation on fine-grain formation and structural character in cast IN718 superalloy[J].Journal of Materials Processing Technology,2003(1/3):35-39. |
| [8] | P.L. Blackwell .The mechanical and microstructural characteristics of laser-deposited IN718[J].Journal of Materials Processing Technology,2005(1/2):240-246. |
| [9] | S. C. Medeiros;Y. V. R. K. Prasad;W. G. Frazier;R. Srinivasan .Microstructural modeling of metadynamic recrystallization in hot working of IN 718 superalloy[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2000(1/2):198-207. |
| [10] | G. Appa Rao;M. Srinivas;D. S. Sarma .Effect of solution treatment temperature on microstructure and mechanical properties of hot isostatically pressed superalloy Inconel 718[J].Materials Science and Technology: MST: A publication of the Institute of Metals,2004(9):1161-1170. |
| [11] | Slama C.;Abdellaoui M. .Structural characterization of the aged Inconel 718[J].Journal of Alloys and Compounds: An Interdisciplinary Journal of Materials Science and Solid-state Chemistry and Physics,2000(1/2):277-284. |
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