Computational simulation on deformation behavior of CT specimens of TRIP steel under mode I loading for evaluation of fracture toughness

Abstract Past experimental studies have revealed that TRIP steel possesses favorable fracture toughness because of strain-induced martensitic transformation during large plastic deformation. However, problems associated with the mechanism of high fracture toughness are still unclear. The prediction and control of the deformation and transformation behaviors of TRIP steel near the crack tip are indispensable for obtaining the required fracture toughness. Here, the deformation behaviors of CT specimens of TRIP steel are simulated by FEM under mode I loading at various temperatures for the cases of stationary cracks and stable crack extensions. In the case of a stable crack extension, the nodal release technique and concept of pull-back force are introduced. The fracture toughnesses for TRIP steel and an austenitic material without martensitic transformation are also calculated by path integrals such as J and T ∗ integrals. The mechanism of high fracture toughness due to strain-induced martensitic transformation for the case of stationary crack is discussed by comparing the computational results for TRIP steel with those for austenitic material. Then, the mechanism of strain-induced martensitic transformation toughening for TRIP steel due to crack extension is investigated.

[1]  R. G. Stringfellow,et al.  A constitutive model for transformation plasticity accompanying strain-induced martensitic transformations in metastable austenitic steels , 1992 .

[2]  Su Qing-ping,et al.  Effect of dual-scale microstructure on the toughness of laminar zirconia composites , 1996 .

[3]  V. F. Zackay,et al.  Fracture and fractography of metastable austenites , 1971 .

[4]  Transformation toughening in dispersed-phase systems , 2003 .

[5]  K. Hwang,et al.  A micromechanics constitutive model of transformation plasticity with shear and dilatation effect , 1991 .

[6]  S. Antolovich,et al.  Observations of martensite formation and fracture in TRIP steels , 1970, Metallurgical and Materials Transactions B.

[7]  Satya N. Atluri,et al.  Computational methods in the mechanics of fracture , 1987, International Journal of Fracture.

[8]  Gregory B Olson,et al.  Transformation plasticity and toughening , 1996 .

[9]  S. Antolovich,et al.  Fatigue crack propagation in trip steels , 1972 .

[10]  V. F. Zackay,et al.  PRELIMINARY TOUGHNESS RESULTS ON TRIP STEEL. , 1968 .

[11]  S. Atluri,et al.  Further studies on elastic-plastic stable fracture utilizing the T∗ integral , 1985 .

[12]  J. Rice.  A path-independent integral and the approximate analysis of strain , 1968 .

[13]  Satya N. Atluri,et al.  Incremental path-independent integrals in inelastic and dynamic fracture mechanics , 1984 .

[14]  Simona Socrate,et al.  Mechanics of microvoid nucleation and growth in high-strength metastable austenitic steels , 1995 .

[15]  A. Needleman,et al.  A tangent modulus method for rate dependent solids , 1984 .

[16]  S. Antolovich,et al.  On the toughness increment associated with the austenite to martensite phase transformation in TRIP steels , 1971 .

[17]  Yoshihiro Tomita,et al.  Investigation on deformation mode dependence of strain-induced martensitic transformation in trip steels and modelling of transformation kinetics , 1998 .

[18]  Yoshihiro Tomita,et al.  Constitutive modeling of TRIP steel and its application to the improvement of mechanical properties , 1995 .

[19]  W. Bamford,et al.  Fracture behavior of stainless steel , 1972 .

[20]  J. Lambropoulos.  Shear, shape and orientation effects in transformation toughening , 1986 .

[21]  Robert M. McMeeking,et al.  Finite deformation analysis of crack-tip opening in elastic-plastic materials and implications for fracture , 1977 .

[22]  Ricardo Henriques Leal,et al.  Transformation toughening of metastable austenitic steels , 1984 .

[23]  V. V. Kosarchuk,et al.  Influence of phase transformations on the mechanical properties of austenitic stainless steels , 2000 .

[24]  S. Atluri,et al.  Direct evaluation of Tε∗ integral from experimentally measured near tip displacement field, for a plate with stably propagating crack , 1999 .

[25]  Satya N. Atluri,et al.  Further studies on the characteristics of the T *ɛ integral: Plane stress stable crack propagation in ductile materials , 1999 .

[26]  E. Werner,et al.  A new view on transformation induced plasticity (TRIP) , 2000 .

[27]  David L. McDowell,et al.  Modeling large strain multiaxial effects in FCC polycrystals , 1996 .

[28]  Y. Tomita,et al.  Estimation of deformation behavior of TRIP steels - smooth/ringed-notched specimens under monotonic and cyclic loading , 2000 .

[29]  J. D. Eshelby.  The determination of the elastic field of an ellipsoidal inclusion, and related problems , 1957, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[30]  C. Young.  Transformation toughening in phosphocarbide-strengthened austenitic steels , 1988 .

[31]  Anthony G. Evans,et al.  Mechanics of Transformation‐Toughening in Brittle Materials , 1982 .

[32]  T. Angel,et al.  Formation of Martensite in Austenitic Stainless Steels , 1954 .

[33]  Gregory B Olson,et al.  Kinetics of strain-induced martensitic nucleation , 1975 .

[34]  D. Parks,et al.  Strain-induced transformation toughening in metastable austenitic steels , 2013 .

[35]  Takeshi Iwamoto,et al.  Computational simulation of the dependence of the austenitic grain size on the deformation behavior of TRIP steels , 2000 .

[36]  T. Mura,et al.  Transformation toughening in ceramic with martensites or micro-cracks , 1991 .

[37]  Y. Tomita,et al.  Plane strain tension of thermo-elasto-viscoplastic blocks , 1990 .

[38]  Frode Stavehaug,et al.  Transformation toughening of [gamma][prime]-strengthened metastable austenitic steels , 1990 .

[39]  K. Hwang,et al.  A continuum analysis of transformation plastic localization in ceramics , 1997 .

[40]  Yoshihiro Tomita,et al.  Bifurcation and post bifurcation behaviour of internally pressurized elastic-plastic circular tubes under plane strain conditions , 1981 .