|
|
Effects of thermal induced porosity on mechanical properties of PM superalloy |
ZHANG Guo-xing1,2, HAN Shou-bo1,2, SUN Zhi-kun1,2 |
1. High Temperature Materials Research Institute, CISRI, Beijing 100081, China 2. Beijing Key Laboratory of Advanced High Temperature Materials, Beijing 100081, China |
|
|
Abstract Thermal induced porosity (TIP) is one of the three major defects in PM superalloy, which has a significant adverse effect on the alloy performance. PM superalloy parts with TIP were analyzed. The microstructure was observed and the effects of porosity on mechanical properties of the alloy were also studied. The results show that the main cause of TIP is residual gas in hot isostatic pressing canning for the PM superalloy parts with large size and complex shape. The tensile properties under room temperature and impact toughness are greatly reduced with the increase of porosity. When the porosity increases from 0.072% to 1.744%, the tensile strength and yield strength decrease by 28.37% and 17.39%, respectively, while the elongation and reduction of area decrease by 62.0% and 62.5%, respectively. At the same time, impact energy decreases by 58.18%. TIP becomes the source of crack during heat treatment, causing the alloy cracks or cracking.
|
Received: 03 April 2014
Published: 28 February 2015
|
|
|
|
[1] |
张义文,上官永恒.粉末高温合金的研究与发展[J].粉末冶金工业, 2004, 14(6):30-43
|
[2] |
张义文.高温合金粉末内部孔洞的研究概况[J].钢铁研究学报, 2002, 14(3):73-76
|
[3] |
郭建亭.高温合金材料学(中册)-制备工艺[M]. 北京: 科学出版社,2008.
|
[4] |
Shahid B,Plippe T,Stephen D A.Low Cycle Fatigue of As-HIP and HIP + Forged René95[J].Metallurgical Transactions A, 1979, 10(10):1481-1490
|
[5] |
Miner R V,Dreshfield R L.Effects of fine porosity on the fatigue behavier of a powder metallurgy superalloy [J][J].Metallurgical Transactions A, 1981, 12(2):261-267
|
[6] |
Dreshfield R L,Miner R V.Effects of Thermal Induced porosity on an as-HIP powder metallurgy superalloy[J].PMI, 1980, 12(2):83-87
|
|
|
|