Static strain aging of stabilized ferritic stainless steels

Abstract

Static strain aging (SSA) of stabilized ferritic stainless steels of type 1.4509 (AISI ‘441’) and 1.4521 (AISI 444)
was investigated. The test materials were prestrained to a 5% tensile elongation and subsequently aged at low
temperatures ranging from 150°C to 250°C for 1800 seconds. The results show that stabilized ferritics are
indeed susceptible to static strain aging. The elevated yield point returned in both grades aged above 200ºC.
Furthermore, strength increments in the order of 50 MPa were achieved. This indicates that strain aging might
be used as a hardening mechanism for this type of steels.