Mechanical Engineering

A structural component in the form of a wide plate is to be fabricated from a steel alloy that has a plane strain fracture toughness of and a yield strength of 1400 MPa (205,000 psi). The flaw size resolution limit of the flaw detection apparatus is 4.0 mm (0.16 in.). If the design stress is one-half the yield strength and the value of Y is 1.0, determine whether or not a critical flaw for this plate is subject to detection.

A structural component in the form of a wide plate is to be fabricated from a steel alloy that has a plane strain fracture toughness of and a yield strength of 1400 MPa (205,000 psi). The flaw size resolution limit of the flaw detection apparatus is 4.0 mm (0.16 in.). If the design stress is …

A structural component in the form of a wide plate is to be fabricated from a steel alloy that has a plane strain fracture toughness of and a yield strength of 1400 MPa (205,000 psi). The flaw size resolution limit of the flaw detection apparatus is 4.0 mm (0.16 in.). If the design stress is one-half the yield strength and the value of Y is 1.0, determine whether or not a critical flaw for this plate is subject to detection. Read More »

Steady-state creep rate data are given here for some alloy taken at 200�C (473 K):If it is known that the activation energy for creep is 140000 J/mol, compute the steady-state creep rate at a temperature of 240 �C (513 K) and a stress level of 47 MPa.

Steady-state creep rate data are given here for some alloy taken at 200�C (473 K): If it is known that the activation energy for creep is 140000 J/mol, compute the steady-state creep rate at a temperature of 240 �C (513 K) and a stress level of 47 MPa. EXPERT ANSWER

The fracture strength of glass may be increased by etching away a thin surface layer. It is believed that the etching may alter the surface crack geometry (i.e. reduce crack length and increase tip radius). Calculate the ratio of the etched and original crack tip radii if the fracture strength is increased by a factor of 3 when 46.0% of the crack length is removed.

The fracture strength of glass may be increased by etching away a thin surface layer. It is believed that the etching may alter the surface crack geometry (i.e. reduce crack length and increase tip radius). Calculate the ratio of the etched and original crack tip radii if the fracture strength is increased by a factor …

The fracture strength of glass may be increased by etching away a thin surface layer. It is believed that the etching may alter the surface crack geometry (i.e. reduce crack length and increase tip radius). Calculate the ratio of the etched and original crack tip radii if the fracture strength is increased by a factor of 3 when 46.0% of the crack length is removed. Read More »

A cylindrical 4340 steel bar is subjected to reversed rotating-bending stress cycling, which yielded the test results presented in Animated Figure 8.21. If the maximum applied load is 5,000 N. compute the minimum allowable bar diameter to ensure that fatigue failure will not occur. Assume a factor of safety of 2.25 and that the distance between loadbearing points is 55.0 mm. mm Cycles to failure = 3.2E 3 Maximum stress = 0 Mpa 700 Ti-5Al-2.5Sn titanium alloy 4340 steel Maximum stress, S (MPa) 1045 steel Ductile cast iron 70Cu-30Zn brass 2014-T6 Al alloy EQ21A-T6 Mg alloy 101_10510610_100100* Cycles to failure. N

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The spring mechanism is used as a shock absorber for a load applied to the spring is originally unstretched and the drawbar slides along the smooth guide posts CG: and EF. The ends of all springs are attached to their respective members. Determine the force in spring H when the P = 50 kN force is applied. Express your answer to three significant figures and include appropriate units. Determine the force in spring AG (and, by symmetry, BF) when the P = 50 kN force is applied. Express your answer to three significant figures and include appropriate units. What is the required diameter of the shank of bolts CG and EF if the allowable stress for the bolts is sigma_allow = 135 MPa? Express your answer to three significant figures and include appropriate units

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The spring mechanism is used as a shock absorber for a load applied to the drawbar AB. (Figure 1) Each spring is originally unstretched and the drawbar slides along the smooth guide posts CG and EF. The ends of all springs are attached to their respective members.

The spring mechanism is used as a shock absorber for a load applied to the drawbar AB. (Figure 1) Each spring is originally unstretched and the drawbar slides along the smooth guide posts CG and EF. The ends of all springs are attached to their respective members. a) Determine the force in spring H when the P=65 kN force is applied. Express …

The spring mechanism is used as a shock absorber for a load applied to the drawbar AB. (Figure 1) Each spring is originally unstretched and the drawbar slides along the smooth guide posts CG and EF. The ends of all springs are attached to their respective members. Read More »

To use Mohr’s circle to determine the principal stresses, the maximum in-plane shear stress, and the average normal stress in an element.The state of plane stress on an element is shown below. Let σx=30.0 MPa, σy=−100.0 MPa, and τxy=50.0 MPa.Part A – Construction of Mohr’s circle for the state of stress For the element shown, construct Mohr’s circle for the state of stress shown associated with the x plane.First, select the center of Mohr’s circle (point C) and select the point that represents the state of plane stress shown (point A). Given these two points, determine the length of the line connecting these two points, which represents the radius R of the Mohr’s circle.

Mohr’s Circle: Plane Stress Learning Goal: To use Mohr’s circle to determine the principal stresses, the maximum in-plane shear stress, and the average normal stress in an element. The state of plane stress on an element is shown below. Let σx=30.0 MPa, σy=−100.0 MPa, and τxy=50.0 MPa. Part A – Construction of Mohr’s circle for the state of stress …

To use Mohr’s circle to determine the principal stresses, the maximum in-plane shear stress, and the average normal stress in an element.The state of plane stress on an element is shown below. Let σx=30.0 MPa, σy=−100.0 MPa, and τxy=50.0 MPa.Part A – Construction of Mohr’s circle for the state of stress For the element shown, construct Mohr’s circle for the state of stress shown associated with the x plane.First, select the center of Mohr’s circle (point C) and select the point that represents the state of plane stress shown (point A). Given these two points, determine the length of the line connecting these two points, which represents the radius R of the Mohr’s circle. Read More »