Andreas Weiß

Segregation-Induced Enhancement of Low-Temperature Tensile Ductility in a Cast High-Nitrogen Austenitic Stainless Steel Exhibiting Deformation-Induced α′ Martensite Formation

In spite of the formation of a high fraction of deformation-induced α′ martensite, the tensile elongation of a cast high-nitrogen austenitic stainless steel was found to enhance at lower temperatures, a behavior deviating from that exhibited by wrought and homogenized austenitic stainless steels. The observed behavior was explained by the presence of microstructural regions with different stabilities with respect to deformation-induced α′ martensite formation caused by the segregation of alloying elements.

Verbesserung der Kaltumformbarkeit austenitischer CrNi-Stähle durch Nutzung des Trip-Effektes

Die Kaltumformbarkeit ist neben der Korrosionsbestandigkeit eine bedeutende Eigenschaft bei der Herstellung und Weiterverarbeitung der austenitischen CrNi-Stahle. Das hohe Kaltumformvermogen dieser Stahle wird masgeblich durch den Trip-Effekt hervorgerufen. Dieser Beitrag der TU Bergakademie Freiberg behandelt Verfahren zur Ausschopfung der Werkstoffreserven bezuglich eines hohen Kaltumformvermogens.

Improvement of the cold workability of austenitic CrNi steels using the trip effect

For the production and further processing of the austenitic CrNi steels the cold workability is a significant property in addition to the corrosion resistance. The high cold deformation behaviour of these steels is caused to a high degree by the trip effect. This article of the TU Bergakademie Freiberg deals with methods concerning material ressources relating to a high cold deformation.

Magnetic measurement of strain-induced martensite formation in Fe–30Ni steel

ABSTRACT This investigation focuses on deformation-induced plasticity in Invar-type steel alloys. The effect is being studied in an austenitic model alloy, containing 30 wt-% of nickel. Its temperature dependent mechanical properties are being presented. Furthermore, the martensitic phase content has been determined by magnetic means in an alloy with two ferromagnetic phases for the first time. The results show that the α′-martensite formation within the austenitic phase with primarily wavy glide mechanism allows an increase in ductility of around 10% at the Msσ temperature of −5°C. This is the point of maximum uniform elongation. Near the Ms temperature, a microstructure of 70 vol.-% deformation-induced α′-martensite can be achieved.