Effect of Selective Heating on Formability and Densification of Powder Metallurgy Preforms During Upsetting
Autor: | S. Kanmani Subbu, R. Tharmaraj, M. Joseph Davidson |
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Rok vydání: | 2019 |
Předmět: |
010302 applied physics
Materials science Hydraulic press 0211 other engineering and technologies chemistry.chemical_element 02 engineering and technology Flow stress Strain rate 01 natural sciences law.invention chemistry law Aluminium Powder metallurgy 0103 physical sciences Formability Relative density Composite material Deformation (engineering) 021102 mining & metallurgy |
Zdroj: | Transactions of the Indian Institute of Metals. 72:1289-1298 |
ISSN: | 0975-1645 0972-2815 |
DOI: | 10.1007/s12666-019-01625-z |
Popis: | In this work, a new method of selective heating is proposed to increase the deformation behaviour of cylindrical sintered aluminium preforms during the process. Initially, cold upsetting is carried out using 0.5 MN hydraulic press machine at 0.1 s−1 strain rate and the failure locations of the preforms are predicted for various initial relative densities with the aspect ratio of 1 during the deformation process. After the prediction of this failure location, various conditions of selective heating are attempted uniformly on the deformed preforms after a certain stage of deformation before the onset of the failure initiation, using portable gas cartridge at a different temperature and time to assess their consequence on formability behaviour. The detailed experimental results are evaluated for the formability of the selectively heated preforms under different variables such as flow stress, relative density, axial strain, formability stress index and stress ratio parameter. As a result, the initiation of failure and its progression can be delayed by selectively heating the samples before the onset of the failure initiation. Selective heating of the failure location may relieve the accumulated stresses and delay the onset of failure to a later strain level thereby increasing the formability of the metal. |
Databáze: | OpenAIRE |
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