About this Abstract |
Meeting |
MS&T24: Materials Science & Technology
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Symposium
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Additive Manufacturing: Microstructure, Defects, and Properties
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Presentation Title |
A Novel Approach to Develop a Shorter Heat Treatment Under Hot Isostatic Pressure for Electron Beam Melted Alloy 718 |
Author(s) |
Ajinkya Sampatrao Ghorpade, Ujjwal Prakash, Shrikant Joshi |
On-Site Speaker (Planned) |
Ajinkya Sampatrao Ghorpade |
Abstract Scope |
In the present study IN718 was fabricated using Electron beam melting (EBM). These samples were subjected to two different heat treatments after HIPing at 1120℃ and 100 MPa for four hours. The standard heat treatment (ASTM F3055) involves a solution treatment (954℃/1h) followed by a two-step aging (740℃/8h + 635℃/8h) cycle (HIP+STA). In the second heat treatment, aging time (740℃/4h + 635℃/1h) was reduced by maintaining HIPing pressure throughout the cycle (combined HIP cycle). The yield strength of combined HIP cycle sample was higher than the HIP+STA sample. This may be attributed to the higher precipitation strengthening in combined HIP cycle (701 MPa) than HIP+STA sample (551 MPa). The difference in precipitation strengthening may be attributed to the volume fraction, aspect ratio and size of the precipitates present. The combined HIP cycle is recommended as it leads to best mechanical properties. |