Influence of Heat Treatments on the Impact Toughness of a Ti-stabilized 12%Cr Supermartensitic Stainless Steel

The supermartensitic stainless steels (SMSS) are a relatively new class of corrosion resistant alloys developed to obtain a better combination of weldability, strength, toughness and corrosion resistance than conventional martensitic stainless steels. The final properties of SMSS are strongly influenced by quenching and tempering heat treatments. In this work, different routes of heat treatments were tested in a Ti-stabilized 12%Cr supermartensitic stainless steel with the objective to improve mechanical properties, specially the low temperature (-46ºC) toughness. Double and triple quenching were tested and compared to single quenching heat treatments. Two tempering temperatures (500ºC and 650ºC) were tested. The results obtained with instrumented Charpy impact tests showed that a triple quenching treatment was able to increase the density of fine TiC particles and improve the mechanical properties of specimens heat treated by quenching and tempering at 650ºC

Development of a Methodology for Structural and Mechanical Characterization of Extended Sheets Made from Stainless Steels

Extended sheets are produced by a pressure cutting process to transform common sheets in expanded metal. These sheets are usually made of carbon steel, but due to their corrosion susceptible, studies have been developed with the aim to evaluate the viability of replacing these common steels by stainless steels. This study proposed an experimental method to characterize structural and mechanically samples of stainless steel extended sheets (410D, 444A, 439 and 304A) and a 1010 carbon steel sheet thicker than the others. This study has a practical importance because nowadays there are not standardized procedures to do this kind of evaluation. The obtained results showed that the methodology was effective for the proposed objective and that the expanded sheets made of stainless steels have a better performance in terms of mechanical strength compared to the 1010 steel sheet