Impact of iron composition on the properties of an additively Manufactured solid solution strengthened nickel base alloy

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:718

Article

Khayat, Z. R.¹  Palmer, T. A.^2,3 

[1] Penn State Univ, Appl Res Lab, University Pk, PA 16802 USA

[2] Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16802 USA

[3] Penn State Univ, Dept Engn Sci & Mech, University Pk, PA 16802 USA

关键词: Additive manufacturing;    Inconel (R) 625;    Directed energy deposition;    Iron composition;    Nickel base alloy;    Hot isostatic pressing;   

DOI  :  10.1016/j.msea.2018.01.112

来源: Elsevier

【 摘 要 】

The impact of changes in Fe content from 1 wt% to 4 wt% on the propel:ties of additively manufacturdd (AM) Inconel (R) 625 fabricated using laser-based directed energy deposition (DED) is investigated in both the as deposited and post processed hot isostatically pressed (HIP) conditions. While similar solidification structures and microhardness values are observed the low Fe content build displayed higher yield (520 MPa +/- 12 MPa vs. 450 MPa +/- 27 MPa) and tensile strengths (860 MPa +/- 27 MPa vs. 753 MPa +/- 25 MPa) and lower. elongations (36% +/- 5% vs. 44% 9%) in the as-deposited condition. Differences in mechanical properties are connected to differences in the grain size produced with the different Fe contents. In. the as deposited condition,, fine grains less than 500 pm in size with low aspect ratios were oberved with the low Fe content, while large elongated grains in excess of 1 mm in length were observed with the high Fe content. After HIP, the yield strengths for both Fe contents decreased by 14%, while elongation increased siinilarly: On the other hand, tensile strengths after post processing chariged by only 3%, which were correlated to higher levels of strain hardening for the higher Fe content. These differences in behavior can be attributed, in part to changes in precipitate morphologies. After HIP post processing, the low Fe content build displayed Nb and Mo rich precipitates, while spherical Ti rich precipitates are present in the high Fe content build.

【 授权许可】

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