일렉트로슬래그 클래딩으로 그물망 용접조직을 갖는 새로운 420계
스테인레스강 스트립재의 질소함량과 냉간압하량에 따른 기계적 특성 변 |
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The Effects of Nitrogen Content and Cold rolling reduction on the Mechanical Properties
of New 420-series Stainless Steel Strip having a Mesh As-Welded Structure
by the Electroslag Cladding |
Jae-Young Jung* |
Correspondence:
Jae-Young Jung, Email: jaeyjung7@gmail.com |
Received: 10 August 2017 • Accepted: 26 September 2017 |
Abstract |
In this study, we investigated the mechanical properties of new 420 stainless steel strips as a function of
nitrogen content and cold rolling reduction. Also, the results of the tensile and thermal fatigue tests using
electroslag cladding specimens under a given welding condition were as follows. As-welded structures in
which the delta ferrite is present in the form of a mesh are obtained in the alloy composition range in which
about 5% delta ferrite is present in the Schaeffler diagram based on Cr equivalent and Ni equivalent. The
softening temperature of new 420 stainless steel alloy designed as a mesh as-welded structure was determined
to be 680-730℃ as a result of using cold rolled steel at 10-90% reduction. The ratio of 600℃ to
room temperature tensile yield strength of weld metal was ~0.37 for the lowest N specimen and ~0.485 for
the highest N specimen. However, high temperature ductility deteriorated with increasing N content. The
presence of welding beads between the weld metal also reduced the elongation at room and high temperature
rather than yield and tensile strength. The thermal fatigue characteristics are almost equal or better than
those of the same materials prepared by the submerged welding method. |
Key Words:
Electroslag cladding, New 420-series stainless steel strip, A mesh as-welded structure, Martensite stainless steel overlay, Cold rolled strip |