Mechanism of low temperature brittle fracture in high nitrogen bearing austenitic steels

被引:143
作者
Tomota, Y
Xia, Y
Inoue, K
机构
[1] Univ Washington, Dept Mat Sci & Engn, Seattle, WA 98195 USA
[2] Ibaraki Univ, Hitachi, Ibaraki 316, Japan
关键词
D O I
10.1016/S1359-6454(97)00350-9
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Low temperature embrittlement is studied for three high-nitrogen bearing austenitic steels, 18Mn-18Cr-0.5N, 18Mn-18Cr-0.8N and 17Cr-13Ni-2Mo-0.5N (all in mass%) steels. These steels ail show ductile-to-brittle transition behavior. They have fractured in a cleavage-like mode when tested at 77 K by a Charpy impact tester and the fractured surfaces have shown facets along {111} planes identified by using etch-pits and scanning electron microscopy. Slip traces have frequently been observed on flat facets and fracture has taken place along {111} planes by slipping-off, i.e. separation occurring along an active slip plane with a high density of dislocations. Transmission electron microscopy has revealed that there are many arrays of planar dislocations and dislocation bands just below the fractured surface. Neither twinning nor epsilon martensite has been observed. Fracture characteristics observed are primarily related to brittle fracture occurring along active slip planes by slipping-off, not by the cleavage fracture associated with occurrence of mechanical twinning. (C) 1998 Acta Metallurgica Inc.
引用
收藏
页码:1577 / 1587
页数:11
相关论文
共 16 条
[1]   NITROGEN STRENGTHENING OF A STABLE AUSTENITIC STAINLESS-STEEL [J].
BYRNES, MLG ;
GRUJICIC, M ;
OWEN, WS .
ACTA METALLURGICA, 1987, 35 (07) :1853-1862
[2]  
DEFILIPPI J, 1968, T SOC AIME, V245, P2141
[3]   ANALYSIS OF FE-NI-CR-N AUSTENITE USING THE EMBEDDED-ATOM METHOD [J].
GRUJICIC, M ;
ZHOU, XW .
CALPHAD-COMPUTER COUPLING OF PHASE DIAGRAMS AND THERMOCHEMISTRY, 1993, 17 (04) :383-413
[4]   THE CORE STRUCTURE OF (A/2)[110] SCREW DISLOCATIONS IN FE-NI-CR-N AUSTENITE [J].
GRUJICIC, M .
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, 1994, 183 (1-2) :223-232
[5]   MODELS OF SHORT-RANGE ORDER IN A FACE-CENTERED-CUBIC FE-NI-CR ALLOY WITH A HIGH-CONCENTRATION OF NITROGEN [J].
GRUJICIC, M ;
OWEN, WS .
ACTA METALLURGICA ET MATERIALIA, 1995, 43 (11) :4201-4211
[6]  
ISHIZAKA J, 1992, TETSU TO HAGANE, V78, P1846
[7]   BRITTLE-FRACTURE IN AUSTENITIC STEEL [J].
MULLNER, P ;
SOLENTHALER, C ;
UGGOWITZER, PJ ;
SPEIDEL, MO .
ACTA METALLURGICA ET MATERIALIA, 1994, 42 (07) :2211-2217
[8]   ON THE EFFECT OF NITROGEN ON THE DISLOCATION-STRUCTURE OF AUSTENITIC STAINLESS-STEEL [J].
MULLNER, P ;
SOLENTHALER, C ;
UGGOWITZER, P ;
SPEIDEL, MO .
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, 1993, 164 (1-2) :164-169
[9]  
Speidel M.O., 1991, STAINLESS STEELS 91, V1, P25
[10]   CLEAVAGE-LIKE FRACTURE ALONG SLIP PLANES IN FE-18CR-3NI-13MN-0.37N AUSTENITIC STAINLESS-STEEL AT LIQUID-HELIUM TEMPERATURE [J].
TOBLER, RL ;
MEYN, D .
METALLURGICAL TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, 1988, 19 (06) :1626-1631