Problem 1. Consider a double-edge-notched plate made of AISI4130 steel (u= 817 MPa) is subjected to...

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Problem 1. Consider a double-edge-notched plate made of AISI4130 steel (u= 817 MPa) is subjected to an axial force P, as in Figure 1b. W = 38.10 mm, w = 57.15 mm, p = 8.06 mm, t = 5.0 mm. Answer the following questions: (a) Determine the notch factors kt and kf using Peterson's approach and Neuber's approach. (b) Assume the fatigue limit for smooth member is e = 0.5u, what completely reversed force amplitude Pa can be applied to the notched member for 106 cycles? 3.0 3.0 W/w=2.0 1.5 2.6 2.6 1.2 1.1 Kt 2.2 1.8 (a) 2.2 1.05 1.8 (b) 1.4 +00 P P W S= + 1.4 W1 W2 P (w - d)t P S= Wt P 1.0 1.0 0 0.1 0.2 0.3 0.4 0.5 0.6 0 0.05 d/w 10 0.1 0.15 0.2 0.25 0.3 p/W 3.0 W2/W=2 2.6 1.5 2.2 1.2 Kt 1.8 1.1 1.02 1.4 G 3.0 W2 W W2 2.6 W1 M P P 2.2 S= Wt W/W1=3 6M S= 1.5 W2t 1.8 1.1. 1.05 1.4 1.02 1.0 1.0 0 0.05 0.1 0.15 0.2 p/W 0.25 0.3 0 0.05 0.1 0.15 0.2 0.25 p/W 0.3 Figure 1 Elastic stress concentration factors for notched plates Notch sensitivity: q = kf1 kt-1 Peterson's approach: q = 1 1+ P log = 2.654 10-7 - 1.309 10u + 0.01103 , mm = 10loga (345 2070 MPa) Neuber's approach: q = 1 1+ P For steels: == -3 log = -1.079 10 + 2.740 10-6 - 3.740 10 + 0.6404 , mm = 10log (345 < u <1725 MPa) For aluminum alloys: log =-9.402 10 + 1.422 10-50 - 8.249 10 + 1.451 , mm = 10log Problem 1. Consider a double-edge-notched plate made of AISI4130 steel (u= 817 MPa) is subjected to an axial force P, as in Figure 1b. W = 38.10 mm, w = 57.15 mm, p = 8.06 mm, t = 5.0 mm. Answer the following questions: (a) Determine the notch factors kt and kf using Peterson's approach and Neuber's approach. (b) Assume the fatigue limit for smooth member is e = 0.5u, what completely reversed force amplitude Pa can be applied to the notched member for 106 cycles? 3.0 3.0 W/w=2.0 1.5 2.6 2.6 1.2 1.1 Kt 2.2 1.8 (a) 2.2 1.05 1.8 (b) 1.4 +00 P P W S= + 1.4 W1 W2 P (w - d)t P S= Wt P 1.0 1.0 0 0.1 0.2 0.3 0.4 0.5 0.6 0 0.05 d/w 10 0.1 0.15 0.2 0.25 0.3 p/W 3.0 W2/W=2 2.6 1.5 2.2 1.2 Kt 1.8 1.1 1.02 1.4 G 3.0 W2 W W2 2.6 W1 M P P 2.2 S= Wt W/W1=3 6M S= 1.5 W2t 1.8 1.1. 1.05 1.4 1.02 1.0 1.0 0 0.05 0.1 0.15 0.2 p/W 0.25 0.3 0 0.05 0.1 0.15 0.2 0.25 p/W 0.3 Figure 1 Elastic stress concentration factors for notched plates Notch sensitivity: q = kf1 kt-1 Peterson's approach: q = 1 1+ P log = 2.654 10-7 - 1.309 10u + 0.01103 , mm = 10loga (345 2070 MPa) Neuber's approach: q = 1 1+ P For steels: == -3 log = -1.079 10 + 2.740 10-6 - 3.740 10 + 0.6404 , mm = 10log (345 < u <1725 MPa) For aluminum alloys: log =-9.402 10 + 1.422 10-50 - 8.249 10 + 1.451 , mm = 10log