PSI - Issue 14

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Nevil Martin Jose et.al/ Structural Integrity Procedia 00 (2018) 000–000 Nevil Martin Jose et.al/ Structural Integrity Procedia 00 (2018) 000–000 Nevil Martin Jose et.al/ Structural Integrity Procedia 00 (2018) 000–000 Nevil Martin Jose et.al/ Structural Integrity Procedia 00 (2018) 000–000 Nevil Martin Jose et.al/ Structural Integrity Procedia 00 (2018) 000–000

Nevil Martin Jose et al. / Procedia Structural Integrity 14 (2019) 403–409 The K Jc value obtained above is then size adjusted for 1T CT specimens (specimens with B=25.4 mm i.e., 1 inch) using the following equation. ������ � 20 � � ���� ������� � 20� � � ������ ��.� � ��� (4) In the next step, the maximum allowable K JC value for the given specimen is determined using Eq. 5. This value is then again size adjusted using Eq.4. ��������� � � ��� �� ������ � � (5) where �� is yield stress of the material at fracture test temperature, equal to 610 MPa for 20MnMoNi55 steel. This data was taken from the work of S. Bhowmik et.al. (2011). If the K JC value obtained for a given specimen from experiment is more than its K JC(limit) value for that specimen, then for further calculations, the specimen’s K JC value is replaced by K JC(limit) value. All the values are obtained in MPa-m 1/2 in this work. The scale parameter K o is then calculated using Eq.6 � � �∑ �� ����� ���� � � � � � ��� � 20 , MPa-m 1/2 (6) The K JC(median) value at the test temperature is then obtained by Eq.7 ���������� � 20 � � � � 20�����2�� ��� (7) The reference temperature T 0 is then determined using Eq. 8 � � � � �.� � �� � �� � �� ���������� ���� �� � (8) Once T o is obtained, the median fracture toughness master curve for the material valid for the temperature range T 0 -50 to T 0 + 50, for 1T specimens is given by Eq. 9 ���������� � �0 � �0����0.019� � � �� (9) The upper and lower tolerance bounds of the master curve can be obtained using the following equation, Eq. 10. ����.��� � 20 � ��� � ��� � .�� �� ��� �11 � ������0.019� � � ��� (10) where 0.xx represents the required cumulative probability level of failure. The results obtained by carrying out the above-mentioned calculations are as given in Table. 2 Table 2. K JC values obtained after calculations i K JC( i ) (MPa-m 1/2 ) K JC(limit) (MPa-m 1/2 ) 1 190.98 91.67 2 188.27 93.76 3 179.88 93.61 4 84.29 95.67 5 171.17 89.68 6 174.25 91.54 7 67.36 89.09 From the table, it is seen that only two specimens have their K JC values less than their K JC(limit) values. So, the no. of valid tests, r , is only two. Other data needs to be censored with K JC(limit) values. (However, ASTM E1921 specifies that minimum six valid tests are required). The fracture toughness master curve obtained from this data set is given in Fig. 5. The reference temperature T 0 obtained from this data set is -109 0 C. The value of T 0 obtained from D. McCabe et. al (2005) and S. Bhowmik et.al, (2011) for standard specimens are 120 0 C and 129 0 C, respectively The K Jc value obtained above is then size adjusted for 1T CT specimens (specimens with B=25.4 mm i.e., 1 inch) using the following equation. ������ � 20 � � ���� ������� � 20� � � ������ ��.� � ��� (4) In the next step, the maximum allowable K JC value for the given specimen is determined using Eq. 5. This value is then again size adjusted using Eq.4. ��������� � � ��� �� ������ � � (5) where �� is yield stress of the material at fracture test temperature, equal to 610 MPa for 20MnMoNi55 steel. This data was taken from the work of S. Bhowmik et.al. (2011). If the K JC value obtained for a given specimen from experiment is more than its K JC(limit) value for that specimen, then for further calculations, the specimen’s K JC value is replaced by K JC(limit) value. All the values are obtained in MPa-m 1/2 in this work. The scale parameter K o is then calculated using Eq.6 � � �∑ �� ����� ���� � � � � � ��� � 20 , MPa-m 1/2 (6) The K JC(median) value at the test temperature is then obtained by Eq.7 ���������� � 20 � � � � 20�����2�� ��� (7) The reference temperature T 0 is then determined using Eq. 8 � � � � �.� � �� � �� � �� ���������� ���� �� � (8) Once T o is obtained, the median fracture toughness master curve for the material valid for the temperature range T 0 -50 to T 0 + 50, for 1T specimens is given by Eq. 9 ���������� � �0 � �0����0.019� � � �� (9) The upper and lower tolerance bounds of the master curve can be obtained using the following equation, Eq. 10. ����.��� � 20 � ��� � ��� � .�� �� ��� �11 � ������0.019� � � ��� (10) where 0.xx represents the required cumulative probability level of failure. The results obtained by carrying out the above-mentioned calculations are as given in Table. 2 Table 2. K JC values obtained after calculations i K JC( i ) (MPa-m 1/2 ) K JC(limit) (MPa-m 1/2 ) 1 190.98 91.67 2 188.27 93.76 3 179.88 93.61 4 84.29 95.67 5 171.17 89.68 6 174.25 91.54 7 67.36 89.09 From the table, it is seen that only two specimens have their K JC values less than their K JC(limit) values. So, the no. of valid tests, r , is only two. Other data needs to be censored with K JC(limit) values. (However, ASTM E1921 specifies that minimum six valid tests are required). The fracture toughness master curve obtained from this data set is given in Fig. 5. The reference temperature T 0 obtained from this data set is -109 0 C. The value of T 0 obtained from D. McCabe et. al (2005) and S. Bhowmik et.al, (2011) for standard specimens are 120 0 C and 129 0 C, respectively The K Jc value obtain d above is then size adjusted for 1T CT specimens (specimens with B=25.4 mm i.e., 1 inch) using the following equation. ������ � 20 � ���� ������� 20� � � �� ��� ��.� � ��� (4) In the next step, the maximum allowable K JC value for the given specimen is determined using Eq. 5. This value is then again size adjusted using Eq.4. ��������� ��� � ������ � � (5) here �� is yield st ess of the aterial at fracture test te perature, equal to 610 Pa for 20 n o i55 steel. This data as taken from the ork of S. Bho ik et.al. (2011). If the K JC value obtained f r a given speci en fro experi ent is ore than its JC(limit) value for that speci en, then for further calculations, the specimen’s K JC value is replaced by JC(limit) value. ll the values are obtained in Pa- 1/2 in this ork. The scale parameter K o is then calculated using Eq.6 � � �� ����� ���� � � � � � ��� 20 , Pa- 1/2 (6) The JC(median) value at the test temperature is then obtained by Eq.7 ���������� 20 � � � 20�����2�� ��� (7) The reference te perature T 0 is then determined using Eq. 8 � � � � �.��� � �� � �� ���������� ���� �� � (8) nce T is obtained, the edian fracture toughness master curve for the aterial valid for the te perature range T 0 -50 to T 0 + 50, for 1T specimens is given by Eq. 9 ���������� �0 �0����0.019� � � �� (9) The upper and lo er tolerance bounds of the aster curve can be obtained using the following equation, Eq. 10. ����.��� � 20 � ��� � ��� � .�� �� ��� �11 � ������0.019� � � ��� (10) where 0.xx represents the required cu ulative probability level of failure. The results obtained by carrying out the above- entioned calculations are as given in Table. 2 Table 2. K JC values obtained after calculations i K JC( i ) (MPa-m 1/2 ) K JC(limit) (MPa 1/2 ) 1 90 98 91 67 2 88 27 76 3 179.88 3. 1 4 84.29 95. 7 5 1 17 89 68 6 174.25 91.54 7 67.36 89.09 Fro the table, it i seen that only t o speci ens hav their JC values less than th ir K JC(limit) values. So, the no. of valid tests, r , s only two. Other data needs to be censored with K JC(limit) values. (However, ASTM E1921 pecifies that m nimum six valid t sts are required). The fracture toughnes master curve obtained from this data set is given in Fig. 5. The reference temperature T 0 obtained from this data set is -109 0 C. The value of T 0 obtained fro . cCabe et. al (2005) and S. Bho ik et.al, (2011) for standard speci ens are 120 0 C and 129 0 C, respectively The K Jc value obtained above is then size adjusted for 1T CT specimens (specimens with B=25.4 mm i.e., 1 inch) using the following equation. ������ � 20 � � ���� ������� � 20� � � ������ ��.� � ��� (4) In the next step, the maximum allowable K JC value for the given specimen is determined using Eq. 5. This value is then again size adjusted using Eq.4. ��������� � � ��� �� ������ � � (5) where �� is yield stress of the material at fracture test temperature, equal to 610 MPa for 20MnMoNi55 steel. This data was taken from the work of S. Bhowmik et.al. (2011). If the K JC value obtained for a given specimen from experiment is more than its K JC(limit) value for that specimen, then for further calculations, the specimen’s JC value is replaced by K JC(limit) value. All the values are obtained in MPa-m 1/2 in this work. The scale parameter K o is then calculated using Eq.6 � � �∑ �� ����� ���� � � � � � ��� � 20 , MPa-m 1/2 (6) The K JC(median) value at the test temperature is then obtained by Eq.7 ���������� � 20 � � � � 20�����2�� ��� (7) The reference temperature T 0 is then determined using Eq. 8 � � � � �.� � �� � �� � �� ���������� ���� �� � (8) Once T o is obtained, the median fracture toughness master curve for the material valid for the temperature range T 0 -50 to T 0 + 50, for 1T specimens is given by Eq. 9 ���������� � �0 � �0����0.019� � � �� (9) The upper and lower tolerance bounds of the master curve can be obtained using the following equation, Eq. 10. ����.��� � 20 � ��� � ��� � .�� �� ��� �11 � ������0.019� � � ��� (10) where 0.xx represents the required cumulative probability level of failure. The results obtained by carrying out the above-mentioned calculations are as given in Table. 2 Table 2. K JC values obtained after calculations i K JC( i ) (MPa-m 1/2 ) K JC(limit) (MPa-m 1/2 ) 1 190.98 91.67 2 188.27 93.76 3 179.88 93.61 4 84.29 95.67 5 171.17 89.68 6 174.25 91.54 7 67.36 89.09 From the table, it is seen that only two specimens have their K JC values less than their K JC(limit) values. So, the no. of valid tests, r , is only two. Other data needs to be censored with K JC(limit) values. (However, ASTM E1921 specifies that minimum six valid tests are required). The fracture toughness master curve obtained from this data set is given in Fig. 5. The reference temperature T 0 obtained from this data set is -109 0 C. The value of T 0 obtained from D. McCabe et. al (2005) and S. Bhowmik et.al, (2011) for standard specimens are 120 0 C and 129 0 C, respectively The K Jc value obtain d above is then size adjusted for 1T CT specimens (specimens with B=25.4 mm i.e., 1 inch) using the following equation. ������ � 20 � ���� ������� 20� � � ������ ��.� � ��� (4) In the next step, the maximum allowable K JC value for the given specimen is determined using Eq. 5. This value is then again size adjusted using q.4. ��������� ��� �� ������ � � (5) where �� is yield stress of the material at fracture test temperature, equal to 610 MPa for 20MnMoNi55 steel. his data as taken fro the ork of S. Bhowmik et.al. (2011). If the JC value obtained for a given specimen from experiment is more than its K JC(limit) value for that specimen, then for further calculations, the specimen’s JC value is repl ced by JC(limit) value. ll the values are obtained in MPa-m 1/2 in this work. The scale parameter K o is then calculated using Eq.6 � � �� ����� ���� � � � � � ��� 20 , MPa-m 1/2 (6) The K JC(median) value at the test temperature is then obtained by Eq.7 ��� ������ � 20 � � � 20�����2�� ��� (7) The reference temperature T 0 is then determined using Eq. 8 � � �.� � �� � �� � �� ��� ������ ���� �� � (8) nce T o is obtained, the median fracture toughness master curve for the material valid for the temperature range T 0 -50 to T 0 + 50, for 1T specimens is given by Eq. 9 ��� ������ �0 � �0����0.019� � �� (9) he upper and lo er tolerance bounds of the master curve can be obtained using the following equation, q. 10. ����.��� 20 � ��� � ���.�� �� ��� �11 ������0.019� � ��� (10) where 0.xx represents the required cu ulative probability level of failure. The results obtained by carrying out the above- entioned calculations are as given in Table. 2 Table 2. K JC values obtained after calculations i K JC( i ) (MPa-m 1/2 ) K JC(limit) ( Pa 1/2 ) 1 90.98 91.67 2 188.27 93.76 3 179.88 3. 1 4 84.29 95.67 5 171.17 89.68 6 174.25 91.54 7 67.36 89.09 Fro the table, it is seen that only t o speci ens have their JC values less than th ir K JC(limit) values. So, the no. of valid tests, r , is only two. Other data needs to be censored ith JC(limit) values. ( ever, S 1921 pecifies that ini u six valid tests are required). he fracture toughness aster curve obtained fro this data set is given in Fig. 5. The reference temperature T 0 obtained from this data set is -109 0 C. The value of T 0 obtained from D. Mc abe et. al (2005) and S. ho ik et.al, (2011) for standard speci ens are 120 0 and 129 0 , respectively Nevil Martin Jose et.al/ Structural Integrity Procedia 00 (2018) 000–000 The K Jc value obtained above is then size adjusted for 1T CT specimens (specimens with B=25.4 mm i.e., 1 inch) using the following equation. ������ � 20 � � ���� ������� � 20� � � ������ ��.� � ��� (4) In the next step, the maximum allowable K JC value for the given specimen is determined using Eq. 5. This value is then again size adjusted using Eq.4. ��������� � � ��� �� ������ � � (5) where �� is yield stress of the material at fracture test temperature, equal to 610 MPa for 20MnMoNi55 steel. This data was taken from the work of S. Bhowmik et.al. (2011). If the K JC value obtained for a giv n specimen from experiment is more than its K JC(limit) value for that spec men, then for further calculations, the specimen’s K JC value is replaced by K JC(limit) value. All the values are obtained in MPa-m 1/2 in this work. The scale parameter K o is then calculated using Eq.6 � � �∑ �� ���� ���� � � � � � ��� � 20 , MPa-m 1/2 (6) The K JC(median) value at the test temperature is then obtained by Eq.7 ���������� � 20 � � � � 20�����2�� ��� (7) The reference temperature T 0 is then determined using Eq. 8 � � � � �.� � �� � �� � �� ���������� ���� �� � (8) Once T o is obtained, the median fracture toughness master curve for the material valid for the temperature range T 0 -50 to T 0 + 50, for 1T specimens is given by Eq. 9 ���������� � �0 � �0����0.019� � � �� (9) The upper and lower tolerance bounds of the master curve can be obtained using the following equation, Eq. 10. ����.��� � 20 � ��� � ���.�� �� ��� �11 � ������0.019� � � ��� (10) where 0.xx represents the required cumulative probability level of failure. The results obtained by carrying out the above-mentioned calculations are as given in Table. 2 Table 2. K JC values obtained after calculations i K JC( i ) (MPa-m 1/2 ) K JC(limit) (MPa-m 1/2 ) 1 90 98 1 67 2 188.27 93.76 3 9 88 93 1 4 84.29 95.67 5 171.17 89.68 6 1 4.25 91 54 7 67.36 89.09 From the table, it is seen that only two specimens hav their K JC values less than th ir K JC(limit) values. So, the no. of valid tests, r , is only two. Other data needs to be censored with K JC(limit) values. (However, ASTM E1921 specifies that minimum six valid tests are required). The fracture toughness master curve obtained from this data set is giv n in Fig. 5. The reference temperature T 0 obtained from this data set is -109 0 C. The value of T 0 obtained from D. McCabe et. al (2005) and S. Bhowmik et.al, (2011) for standard specimens are 120 0 C and 129 0 C, respectively 5 Nevil Martin Jose et.al/ Structural Integrity Procedia 00 (2018) 000–000 The K Jc value obtained above is then size adjusted for 1T CT specimens (specimens with B=25.4 mm i.e., 1 inch) using the following equation. ������ � 20 � � ���� ������� � 20� � � � ���� ��.� � ��� (4) In t e next step, the maximum allowable K JC value for the given specimen is determined using Eq. 5. This value is then again size adjusted using Eq.4. ��������� � � �� � ������ � � (5) where �� is yield st ess of the material at fracture est temperature, equal to 610 MPa for 20MnMoNi55 steel. This data was taken from the work of S. Bhowmik et.al. (2011). If the K JC value obtained for a given specimen from experiment is more than its K JC(limit) value for that spec men, then for further calculations, the specimen’s K JC value is replaced by K JC(limit) value. All the values are obtained in MPa-m 1/2 in this work. The scale parameter K o is then calculated using Eq.6 � � �∑ �� ����� ���� � � � � � ��� � 20 , MPa-m 1/2 (6) The K JC(median) value at the test temperature is then obtained by Eq.7 ���������� � 20 � � � � 20�����2�� ��� (7) The reference temperature T 0 is then determined using Eq. 8 � � � � �.� � �� � �� � �� ���������� ���� �� � (8) Once T o is obtained, the median fracture toughness master curve for the material valid for the temperature range T 0 -50 to T 0 + 50, for 1T specimens is given by Eq. 9 ���������� � �0 � �0����0.019� � � �� (9) The upper and lower tolerance bounds of the master curve can be obtained using the following equation, Eq. 10. ����.��� � 20 � ��� � ���.�� �� ��� �11 � ������0.019� � � ��� (10) where 0.xx repres nts the equired cumulati probability level of failure. The results obtained by carrying out the above-mentioned calculations are as given in Table. 2 Table 2. K JC values obtained after calculations i K JC( i ) ( Pa-m 1/2 ) K JC(limit) ( Pa-m 1/2 ) 1 190.98 91.67 2 188.27 93.76 3 179.88 93.61 4 84.29 95.67 5 1 17 89 68 6 1 4.25 91 54 7 67.36 89.09 From the table, it is seen that only two specimens have their K JC values less than th ir K JC(limit) values. So, the no. of valid tests, r , is only two. Other data needs to be censored with K JC(limit) values. (H wever, AS M E1921 specifies that minimum six valid tests are required). The fracture toughness master curve obtained from this data set is given in Fig. 5. The reference temperature T 0 obtained from this dat set is -109 0 C. The value of T 0 obtained from D. McCabe et. al (2005) and S. Bhowmik et.al, (2011) for standard specimens are 120 0 C and 129 0 C, respectively 5 Nevil Martin Jose et.al/ Structural Integrity Procedia 00 (2018) 000–000 The K Jc value obtained above is then size adjusted for 1T CT specimens (specimens with B=25.4 mm i.e., 1 inch) using the following equation. ������ � 20 � � ���� ������� � 20� � � ������ ��.� � ��� (4) In t e next step, the maximum allowable K JC value for the given specimen is determined using Eq. 5. This value is then again size adjusted using Eq.4. ��������� � � �� �� ������ � � (5) where �� is yield stress of the materi l at fracture est temperature, equal to 610 MPa for 20MnMoNi55 steel. This data was taken from the work f S. Bhowmik et.al. (2011). If the K JC value obtained for a giv n specimen from experiment is more than its K JC(limit) value for that spec men, then for further calculations, the specimen’s K JC value is replaced by K JC(limit) value. All the values are obtained in MPa-m 1/2 in this work. The scale parameter K o is then calculated using Eq.6 � � �∑ �� ����� ���� � � � � ��� � 20 , MPa-m 1/2 (6) The K JC(median) value at the test temperature is then obtained by Eq.7 ���������� � 20 � � � � 20�����2�� ��� (7) The reference temperature T 0 is then determined using Eq. 8 � � � � �.� � �� � �� � �� ���������� ���� �� � (8) Once T o is obtained, the median fracture toughness master curve for the material valid for the temperature range T 0 -50 to T 0 + 50, for 1T specimens is given by Eq. 9 ���������� � �0 � �0����0.019� � � �� (9) The upper and lower tolerance bounds of the master curve can be obtained using the following equation, Eq. 10. ����.��� � 20 � ��� � ���.�� �� ��� �11 � ������0.019� � � ��� (10) where 0.xx represents the required cumulative probability level of failure. The results obtained by carrying out the above-mentioned calculations are as given in Table. 2 Table 2. K JC values obtained after calculations i K JC( i ) (MPa-m 1/2 ) K JC(limit) (MPa-m 1/2 ) 1 190.98 91.67 2 88.27 76 3 179.88 93.61 4 84.29 5.67 5 1 17 89 68 6 174.25 91.54 7 67.36 89.09 From the table, it is seen hat only two specimens hav their K JC values less than their K JC(limit) values. So, the no. of valid tests, r , is only two. Other data needs to be censored with K JC(limit) values. (However, ASTM E1921 pecifies that m nimum six valid t sts ar required). The fracture toughnes master curve obtained from this data set is given in Fig. 5. The reference temperature T 0 obtained from this data set is -109 0 C. The value of T 0 obtained from D. McCabe et. al (2005) and S. Bhowmik et.al, (2011) for standard specimens are 120 0 C and 129 0 C, 5 Nevil Martin Jose et.al/ Structural Integ ity P ocedia 00 (2018) 000– 00 The K Jc value obtained above is then size adjusted for 1T CT specimens (specimens with B=25.4 mm i.e., 1 inch) using the following equation. ������ � 20 � � ���� ������� � 20� � � ������ ��.� � ��� (4) In t next step, the maximum allowable K JC value for the given specimen is determined using Eq. 5. This value is then again size adjusted using Eq.4. ��������� � � ��� �� ������ � � (5) where �� is yield stress of the mate i l at fracture est temperature, equal to 610 MPa for 20MnMoNi55 steel. This data was taken from the work of S. Bhowmik et.al. (2011). If the K JC value obtained for a giv n specimen from experiment is more than its K JC(limit) value for that spec men, then for further calculations, the speci en’s JC value is rep ce by K JC(limit) value. All the values are obtained in MPa-m 1/2 in this work. The scale parameter K o is then calculated using Eq.6 � � �∑ �� ����� ���� � � � � � ��� � 20 , MPa-m 1/2 (6) The K JC(median) value at the test temperature is then obtained by Eq.7 �������� � � 20 � � � � 20�����2�� ��� (7) The reference temperature T 0 is then determined using Eq. 8 � � � � �.� � �� � �� � �� ���������� ���� �� � (8) Once T o is obtained, the median fracture toughness master curve for the material valid for the temperature range 0 -50 to T 0 + 50, for 1T specimens is given by Eq. 9 ���������� � �0 � �0����0.019� � � �� (9) The upper and lower tolerance bounds of the master curve can be obtained using the following equation, Eq. 10. ����.��� � 20 � ��� � ���.�� �� ��� �11 � ������0.019� � � ��� (10) where 0.xx represents the required cumulative probability level of failure. The results obtained by carrying out the above- entioned calculations are as given in Table. 2 Table 2. K JC values obtained after calculations i K JC( i ) (MPa-m 1/2 ) K JC(limit) (MPa-m 1/2 ) 1 190.98 91.67 2 88 27 76 3 9 88 93 1 4 84.29 5 67 5 1 17 89 68 6 174.25 91.54 7 67.36 89.09 From the table, it is seen hat only two specimens have their K JC values less than their K JC(limit) values. So, the no. of val d tests, r , is only two. Other data needs to be censored with K JC(limit) values. (However, ASTM E1921 pecifies that m nimum six valid t sts ar required). The fracture oughnes master curve obtained from this data set is g v n in Fig. 5. The reference temperature T 0 obtained from this data set is -109 0 C. The value of T 0 obtained from D. McCabe et. al (2005) and S. Bhowmik et.al, (2011) for standard specimens are 120 0 C and 129 0 C,

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