PSI - Issue 14

K. C. Sahoo et.al./ Structural Integrity Procedia 00 (2018) 000 – 000 K. C. Sahoo et.al./ Structural Integrity Procedia 00 (2018) 000 – 000 K. C. Sahoo et.al./ Structural Integrity Procedia 00 (2018) 000 – 000

K.C. Sahoo et al. / Procedia Structural Integrity 14 (2019) 60–67 3.2 Creep rupture life and damage: The variation of creep rupture life with applied stress at different temperatures was shown in fig.6 in log-log scale. The rupture life was found to decrease with applied stress. It follows a power law of the form where ‘m’ and ‘M’ are stress coefficients. The value of ‘m’ and ‘n’ are closed to each other which suggests that deformation and fracture behaviour were controlled by the same mechanics. 3.2 Creep rupture life and damage: The variation of creep rupture life with applied stress at different temperatures was shown in fig.6 in log-log scale. The rupture life was found to decrease with applied stress. It follows a power law of the form where ‘m’ and ‘M’ are stress coefficients. The value of ‘m’ and ‘n’ are closed to each other which suggests that deformation and fracture behaviour were controlled by the same mechanics. 3.2 Creep rupture life and damage: The variation of cr ep rupture life with applied stress at different temperatures was sho n in fig.6 in log-log scale. The rupture life was found to decrease with applied stress. It follows a power law of the form w ere ‘m’ and ‘M’ are stress coefficients. The value of ‘m’ and ‘n’ are closed to each other which suggests that deformation and fracture behaviour were controlled by the same mechanics. K. C. Sahoo et.al./ Structural Integrity Procedia 00 (2018) 000 – 000 3.2 Creep rupture lif and damage: The variation of creep rupture life with applied stress at different temperatures was sho n in fig.6 in log-log scale. The rupture life was found to decrease with applied stress. It follows a power law of the form where ‘m’ and ‘M’ are stress coefficients. The value of ‘m’ and ‘n’ are closed to each other which suggests that deformation and fracture behaviour were controlled by the same mechanics. K. C. Sahoo et.al./ Structural Integrity Procedia 00 (2018) 000 – 000 3.2 Creep rupture life and damage: The variation of creep rupture life with applied stress at different temperatures was sho n in fig.6 in log-log scale. The rupture life was found to decrease with applied stress. It follows a power law of the form w ere ‘m’ and ‘M’ are stress coefficients. The value of ‘m’ and ‘n’ are closed to each other which suggests that deformation and fracture behaviour were controlled by the same mechanics. K. C. Sahoo et.al./ Structural Integrity Procedia 00 (2018) 000 – 000 3.2 Creep rupture life and damage: The variation of creep ruptu e lif wit applied stress at different temperatur s was hown in fig.6 in log-log cale. The rupture life w s found to decrease with applied stress. It follows a power law of the form where ‘m’ and ‘M’ are stress coefficients. The value of ‘m’ and ‘n’ are closed to each other which suggests that deformation and fracture behaviour were controlled by the same mechanics.

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Fig.6 Variation of Applied stress with rupture life at different temperatures Fig.6 Variation of Applied stress with rupture life at different temperatures Fig.6 Variation of Applied stress with rupture life at different temperatures Fig.6 Variation of Applied stress with ru ture life at different temperatures Fig.6 Variation of Applied stress with rupture life at different temperatures Fig.6 Variation of Applied stress with ru ture life at different temperatures through Monkman-Grant relationship ( where is a constant close to unity and C is the Monkman Grant constant. Low value of constant ‘C’ indicated limited contribution of transient primary strain to the overall creep strain and predominance of creep strain accumulation during the tertiary stage of creep deformation. Fig.7 shows the variation of steady state creep rate ( with rupture life (t r ) of the material. The value of and C was found to be 1.03 and 0.03. The variation of t ot with time of rupture t r was shown in Fig.8 It follows a linear equation with (t ot = f.t r ) where the value of ‘f’ was found to 0.39, 0.3 4, 0.22 at 923, 973 and 1023K respectively. It shows that 304HCu SS has spent about 61, 66 and 78% of their creep rupture life in the tertiary stage of creep deformation at 923K, 973K and 1023K respectively. through Monkman-Grant relationship ( where is a constant close to unity and C is the Monkman Grant constant. Low value of constant ‘C’ indicated limited contribution of transient primary strain to the overall creep strain and predominance of creep strain accumulation during the tertiary stage of creep deformation. Fig.7 shows the variation of steady state creep rate ( with rupture life (t r ) of the material. The value of and C was found to be 1.03 and 0.03. The variation of t ot with time of rupture t r was shown in Fig.8 It follows a linear equation with (t ot = f.t r ) where the value of ‘f’ was found to 0.39, 0.3 4, 0.22 at 923, 973 and 1023K respectively. It shows that 304HCu SS has spent about 61, 66 and 78% of their creep rupture life in the tertiary stage of creep deformation at 923K, 973K and 1023K respectively. th ough Monkman-Grant relationship ( where is a constant close to unity and C is the Monkman Grant constant. Low value of constant ‘C’ indicated limited contribution of transient primary strain to the overall creep strain and predomina ce of creep strain accumulation during the tertiary stage of creep deformation. Fig.7 shows the variation of steady state creep rate ( with rupture life (t r ) of the material. The value of a d C was f und to be 1.03 and 0.03. The variation of t ot with time of rupture t r was shown in Fig.8 It follows a linear equation ith (t ot = f.t r ) where the value of ‘f’ was found to 0.39, 0.3 4, 0.22 at 923, 973 and 1023K respectively. It sh ws that 304HCu SS has spent about 61, 66 and 78% of their creep rupture life in the tertiary stage of creep deformation at 923K, 973K and 1023K respectively. through Monkman-Gr t relationship ( where is a const nt close to unity and C is the M nkman Grant constant. Low value of constant ‘C’ indicated limited contribution of transi nt primary strain to t overall creep strain and predominance of creep strain accumulation during the tertiary stage of creep def rmation. Fig.7 shows the variation of steady state creep rate ( with rupture life (t r ) of the material. The value of and C was found to be 1. 3 and 0.03. The variation of t ot with time of rupture t r was shown in Fig.8 It follows a linear equation with (t ot = f.t r ) where the value of ‘f’ was found to 0.39, 0.3 4, 0.22 at 923, 973 and 1023K respectively. It shows that 304HCu SS has spent about 61, 66 and 78% of their creep rupture life in the tertiary stage of creep deformation at 923K, 973K and 1023K respectively. th ough Monkman-Grant r lationship ( wh re is a constant close to unity and C is the Monkman Grant constant. Low value of constant ‘C’ indicated limited contribution of transient primary strain to the overall creep strain and predominance of creep strain accumulation during the tertiary stage of creep deformation. Fig.7 shows the variation of steady state creep rate ( with rupture life (t r ) of the material. The value of and C was found to be 1.03 and 0.03. The variation of t ot with time of rupture t r was shown in Fig.8 It follows a linear equation with (t ot = f.t r ) where the value of ‘f’ was found to 0.39, 0.3 4, 0.22 at 923, 973 and 1023K respectively. It shows that 304HCu SS has spent about 61, 66 and 78% of their creep rupture life in the tertiary stage of creep deformation at 923K, 973K and 1023K respectively. thr ugh Monkman-Gr t relationship ( where is a const nt close to unity and C is the Monkman Grant constant. Low value of constant ‘C’ indicated limited contribution of transient primary strain to th overall creep strain and predominance of creep strain accumulation during the terti ry stage of creep def rmation. Fig.7 shows the v riation of steady state creep rate ( with rupture life (t r ) of the material. T value of and C was found to be 1. 3 and 0.03. The vari tion of t ot with time of rupture t r was shown in Fig.8 It follows a linear equation with (t ot = f.t r ) where the value of ‘f’ was found to 0.39, 0.3 4, 0.22 at 923, 973 and 1023K respectively. It shows that 304HCu SS has spent about 61, 66 and 78% of their creep rupture life in the tertiary stage of creep deformation at 923K, 973K and 1023K respectively. Further, variation of steady state creep rate ( Further, variation of steady state creep rate ( Further, vari tion of ste dy state creep rate ( Further, variation of steady state creep rate ( Further, vari tion of steady state creep rate ( Further, variation of steady state reep rat ( with rupture life (t r ) of this material has been studied with rupture life (t r ) of this material has been studied with rupture life (t r ) of this m terial has been studied with rupture life (t r ) f this material has been studied with rupture life (t r ) of this material has been studied with rupture life (t r ) his material has b en s udied

Fig.7 Variation of steady state creep rate with rupture life of steels Based on continuum damage mechanics approach the damage of the material has been studied through damage tolerance factor (λ) which is defined as the ratio of strain to failure ( to the steady state creep rate ( and rupture life ( )[ F.A. Leckie.,1977 ]. The values of λ between 1.5 and 2.5 suggests that the tertiary stages of creep deformation is due to the growth of creep cavities by diffusive transfer of atoms from cavity surface on to the grain boundary. Further, if the value of λ exceeds 4 then it is due to the microstructural degradation. [H. Semba.,2008]. The value of λ was found to decrease with increase in rupture life. [Fig.9] It was around 2 to 4.5 for 923K, 2.9 to 6.9 for 973K and 2.4 to 8 for 1023K. Fig.7 Variation of steady state creep rate with rupture life of steels Based on continuum damage mechanics approach the damage of the material has been studied through damage tolerance factor (λ) which is defined as the ratio of strain to failure ( to the steady state creep rate ( and rupture life ( )[ F.A. Leckie.,1977 ]. The values of λ between 1.5 and 2.5 suggests that the tertiary stages of creep deformation is due to the growth of creep cavities by diffusive transfer of atoms from cavity surface on to the grain boundary. Further, if the value of λ exceeds 4 then it is due to the microstructural degradation. [H. Semba.,2008]. The value of λ was found to decrease with increase in rupture life. [Fig.9] It was around 2 to 4.5 for 923K, 2.9 to 6.9 for 973K and 2.4 to 8 for 1023K. Fig.7 Variation of steady state creep rate with rupture life of steels Based on continuum damage mechanics approach the damage of the material has b en studied through dam ge tolerance actor (λ) which is defined as the r tio of strain to failure ( to the steady state creep r te ( and rupture li e ( )[ F.A. Leckie.,1977 ]. The values of λ between 1.5 and 2.5 suggests that the tertiary tages of creep deformation is due to the growth of cr ep cavities by diffusive transf r f atoms fr m cavity surface on to the grain boundary. Further, if the value of λ exceeds 4 then it is due to the microstructural degra ation. [H. Semba.,2008]. The value of λ was found to decrease with increase in rupture life. [Fig.9] It was around 2 to 4.5 for 923K, 2.9 to 6.9 for 973K and 2.4 to 8 for 1023K. Fig.7 Variation of steady state creep rate with rupture life of steels Based on continuum damage mechanics approach the damage of the m terial has been studied through damage tolerance factor (λ) which is defined as the ratio of strain to failure ( to th steady state creep rate ( and rupture life ( )[ F.A. Leckie.,1977 ]. The values of λ between 1.5 and 2.5 suggests that the tertiary stages of creep deformation is due to the growth of creep cavities by diffusive transfer of atoms from cavity surface on to the grain boundary. Further, if the value of λ exceeds 4 then it is due to the microstructural degradation. [H. Semba.,2008]. The value of λ was found to decrease with increase in rupture life. [Fig.9] It was around 2 to 4.5 for 923K, 2.9 to 6.9 for 973K and 2.4 to 8 for 1023K. Fig.7 Variation of steady state creep rate with rupture life of steels Bas d on continuum damage mechanics approach the dam ge f the material has b en studied through damage tolerance factor (λ) which is defined as the r tio of strain to failure ( to the steady st te creep r te ( and rupture li e ( )[ F.A. Leckie.,1977 ]. The values of λ between 1.5 and 2.5 suggests that the tertiar tages of creep deformati n is due to the growth of creep cavities by diffusive transfer of atoms fr m cavity surface on to the grain boundary. Further, if the value of λ exce ds 4 then it is due to the microstructur l degradation. [H. Semba.,2008]. The value of λ was found to decrease with increase in rupture life. [Fig.9] It was around 2 to 4.5 for 923K, 2.9 to 6.9 for 973K and 2.4 to 8 for 1023K. Fig.7 Variation of steady state creep rate with rupture life of steels Based on continuum damage mechanics approach the damage of the m terial has b en studied through d mage toleranc factor (λ) which is defined as the ratio of strain to fa lure ( to th steady state creep rate ( and rupture life ( )[ F.A. Leckie.,1977 ]. The values of λ b tween 1.5 and 2.5 suggests that the tertiary sta es of creep deformation is due t the growth of creep cavitie by diffusive transfer of atoms from cavity surface on to the grain boundary. Further, if the value of λ exceeds 4 then it is due to the microstructural degradation. [H. Semba.,2008]. The value of λ was found to decrease with increase in rupture life. [Fig.9] It was around 2 to 4.5 for 923K, 2.9 to 6.9 for 973K and 2.4 to 8 for 1023K.