Grain refinement in medium chromium ferritic stainless steel welds via aluminum powder addition
Grain refinement in medium chromium ferritic stainless steel weld was attempted via elemental (aluminum) powder pre-placement technique prior to melting under a TIG torch. A Box- Behnken experimental design was adopted with current, travel speed and the amount of aluminum powder added as the proc...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
| Published: |
Trans Tech Publications
2012
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| Subjects: | |
| Online Access: | http://irep.iium.edu.my/23363/ http://irep.iium.edu.my/23363/1/AMR.445.717_2012.pdf |
| Summary: | Grain refinement in medium chromium ferritic stainless steel weld was attempted via
elemental (aluminum) powder pre-placement technique prior to melting under a TIG torch. A Box-
Behnken experimental design was adopted with current, travel speed and the amount of aluminum
powder added as the process factors for producing weld pool. The resolidified weld tracks were
characterized using microscopy, microhardness and mechanical testing. The degree of grain
refinement achieved was evaluated using a scaling index known as Grain Refinement Index (GRI).
The findings showed that the GRI is influenced by the concentration of the aluminum powder introduced into the melt pool. Furthermore, high GRI does not necessarily translate to better mechanical properties relative to the conventional weld. This suggests that the grain size effect
might not be the only factor influencing the property of weld metal. However, weld track treated with 0.08mg/mm2 of aluminum powder exhibited about 20% improvement in properties relative to the conventional weld made under the same energy conditions. |
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