Acta Metallurgica Sinica (English Letters) ›› 2019, Vol. 32 ›› Issue (6): 755-763.DOI: 10.1007/s40195-018-0829-y

Special Issue: 2019年腐蚀专辑-1

• Orginal Article • Previous Articles     Next Articles

Effect of Short-Time Aging on the Pitting Corrosion Behavior of a Novel Lean Duplex Stainless Steel 2002

Tian-Yi Sun1, Yan-Jun Guo1, Yi-Ming Jiang1, Jin Li1()   

  1. 1 Department of Materials Science, Fudan University,Shanghai 200433, China
  • Received:2018-06-07 Revised:2018-08-20 Online:2019-06-10 Published:2019-06-17
  • Supported by:
    The authors acknowledge the financial support from the National Natural Science Foundation of China (Grant Nos. 51671059 and 51501041).

Abstract:

The effect of short-time aging in the temperature range between 400 and 1000 °C on the pitting corrosion behavior and mechanical property of a novel lean duplex stainless steel (LDSS) 2002 was investigated through the potentiostatic critical pitting temperature (CPT) tests and the Charpy impact tests. Both the pitting corrosion resistance and the toughness of aged specimens degraded due to the precipitation of detrimental secondary phases and the most significant reduction of CPT and impact energy emerged at 650 °C concurrently. The CPT of LDSS 2002 specimen aged at 650 °C decreased by 28 °C, and the impact energy dropped from 69 to 29 J/cm2 compared with the solution-annealed sample. Transmission electron microscopy characterization showed that the main precipitates in LDSS 2002 were Cr2N and M23C6 along the ferrite-austenite grain boundaries.

Key words: Lean, duplex, stainless, steel, Aging, Pitting, corrosion, Impact, energy, Precipitates