Figure 1 shows R.R. Moore rotating-beam fatigue testing machine used to determine durability of a material....

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Figure 1 shows R.R. Moore rotating-beam fatigue testing machine used to determine durability of a material. Figure 2 shows load diagram, shear force and bending moment diagram and stress ratio to time wave diagram. Estimate fatigue strength of rotating beam specimen made of AISI 1020 HR steel corresponding to a life of 12.5 kilocycles of stress reversal. Based on shear stress, bending moment and stress ratio requirement, estimate the life of the specimen corresponding to a stress amplitude of 252 MPa. Then, determine how many cycles before failure if it occurs at fatigue strength of 500 MPa. The known properties are Sut = 463 MPa, 00-805 MPa, m=0.22 and & = 0.90. Pure bending (zero traverse shear) Test specimen C Ot Revolution counter E various Weights Flexible 9*R coupling Motor 0.300 1750 rpm 110-Volts AC N cycles of tension-to-compression-to-tension Figure 1 Figure 1 shows R.R. Moore rotating-beam fatigue testing machine used to determine durability of a material. Figure 2 shows load diagram, shear force and bending moment diagram and stress ratio to time wave diagram. Estimate fatigue strength of rotating beam specimen made of AISI 1020 HR steel corresponding to a life of 12.5 kilocycles of stress reversal. Based on shear stress, bending moment and stress ratio requirement, estimate the life of the specimen corresponding to a stress amplitude of 252 MPa. Then, determine how many cycles before failure if it occurs at fatigue strength of 500 MPa. The known properties are Sut = 463 MPa, 00-805 MPa, m=0.22 and & = 0.90. Pure bending (zero traverse shear) Test specimen C Ot Revolution counter E various Weights Flexible 9*R coupling Motor 0.300 1750 rpm 110-Volts AC N cycles of tension-to-compression-to-tension Figure 1