Effect of Pores on Nitriding Behavior of 12mass%Cr Ferritic Steel Compacts

Nobuyuki Nakamura, Setsuo Takaki, Youichi Tokunaga

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Effect of pores on the nitriding behavior of 12mass%Cr ferritic steel (SUS410L) compacts in nitrogen gas atmosphere was investigated by means of optical microscopy, chemical analysis and measurement of porosity. Porosity of compacts was controlled by varying presintering time at 1473K and repressing pressure of presintered compacts. Mechanical property of nitrided compacts was also estimated by three-point bending test. The results obtained are as follows: (1) In the nitriding at 1473K, compacts with the open-porosity of more than 5vol.% can easily absorb 0.26 mass% of nitrogen all over the specimen through open pores. When the open-porosity has been reduced to less than 5vol.% by presintering and repressing, however, compacts are nitrided only from the surface, so that the general nitriding rate becomes smaller. (2) 0wing to the absorption of 0.26 mass% nitrogen, ferrite phase changes to austenite and the austenite transforms to martensite on cooling to room temperature.(3) Repressing of sintered compacts is very effective for the densification, and this results in the increase in bending strength of sintered compacts with fully martensitic structure.

Original languageEnglish
Pages (from-to)468-473
Number of pages6
JournalJournal of the Japan Society of Powder and Powder Metallurgy
Volume41
Issue number4
DOIs
Publication statusPublished - Feb 1 1994

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Nitriding
Ferritic steel
Porosity
Nitrogen
Austenite
Bending tests
Densification
Martensite
Bending strength
Optical microscopy
Ferrite
Gases
Cooling
Mechanical properties
Chemical analysis
Temperature

All Science Journal Classification (ASJC) codes

  • Mechanical Engineering
  • Industrial and Manufacturing Engineering
  • Metals and Alloys
  • Materials Chemistry

Cite this

Effect of Pores on Nitriding Behavior of 12mass%Cr Ferritic Steel Compacts. / Nakamura, Nobuyuki; Takaki, Setsuo; Tokunaga, Youichi.

In: Journal of the Japan Society of Powder and Powder Metallurgy, Vol. 41, No. 4, 01.02.1994, p. 468-473.

Research output: Contribution to journalArticle

Nakamura, Nobuyuki ; Takaki, Setsuo ; Tokunaga, Youichi. / Effect of Pores on Nitriding Behavior of 12mass%Cr Ferritic Steel Compacts. In: Journal of the Japan Society of Powder and Powder Metallurgy. 1994 ; Vol. 41, No. 4. pp. 468-473.
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