Evaluation of High-Purity 26Cr-1Mo Ferritic Stainless Steel Welds by Burst Tests

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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Microstructure and mechanical properties of AISI 439 ferritic stainless steel welds without filler metal

Acta Universitaria ◽

10.15174/au.2019.2351 ◽

2019 ◽

Vol 29 ◽

pp. 1-12

Author(s):

Juan Manuel Salgado López ◽

Marc Preud homme ◽

Francisco Lopez Monroy ◽

Jose Luis Ojeda Elizarráraz ◽

Arturo Toscano Giles

Keyword(s):

Mechanical Properties ◽

Stainless Steel ◽

Tensile Test ◽

Grain Growth ◽

Ferritic Stainless Steel ◽

Filler Metal ◽

Testing Machine ◽

Thin Plates ◽

Technical Literature ◽

Steel Welds

In literature, it has been reported that a current intensity lower than 120 A leads to a microstructure without grain growth in the heat affected zone (HAZ) of ferritic stainless steel welds. Nevertheless, in technical literature there is little information about the reduction in mechanical properties of ferritic stainless steel welds without filler metal due to grain growth in the HAZ. In this work, thin plates of ferritic stainless 439 steel were welded using pulse current gas tungsten arc welding (P-GTAW) without filler metal. The microstructures in the HAZ were analyzed and the mechanical properties on the welded joint were found by tensile test. This was carried out by cutting samples for the tensile test from the weldments and then tested in a universal testing machine. The fracture surface were observed using scanning electron microscope.

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Effect of Titanium on Oxidation Behavior of High-Purity Ferritic Stainless Steel

MATERIALS TRANSACTIONS ◽

10.2320/matertrans.mt-m2019123 ◽

2019 ◽

Vol 60 (9) ◽

pp. 1968-1976

Author(s):

Yoshiharu Inoue ◽

Nobuhiko Hiraide ◽

Atsutaka Hayashi ◽

Kohsaku Ushioda

Keyword(s):

Stainless Steel ◽

Ferritic Stainless Steel ◽

High Purity ◽

Oxidation Behavior

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