Question-1 A 70% Cu-30% Zn brass wire is cold-drawn 20 percent to a diameter of 2.80 mm. The wire is then further cold- drawn to a diameter of 2.45 mm. (a) Calculate the total percent cold work that the wire undergoes. (b) Estimate the wire's tensile and yield strengths and elongation.

Question-7. Steady-state creep data taken for an alloy at a stress level of 160 MPa are given below. The stress exponent n for the alloy is 6.8. R is 8.3145 J/mol-K. Compute the steady-state creep rate at 1000 °C and a stress level of 68 MPa. Es (h-1) 6.8 × 10-5 T (°C) 800 8.6 x 10-3 900

Following is the Tensile stress-strain data for several hypothetical metals to be used. Answer the following questions referring to table 1.1. Table 1.1: Material Property Data Material Tensile Strength Fracture Strength Strain at Strength (MPa) (MPa) 340 265 550 505 112 150 Fracture before yielding A B C D 0.23 0.15 0.40 a. Which will experience the greatest percent reduction in area? Why? b. Which is the strongest? Why? c. Which is the stiffest? Why? Elastic Modulus (GPa) 210 310 180 400

Sketch Figure 1.3, curve b (a ductile metal). Label it with the following terms, indicating from which location on the curve each quantity can be identified or extracted: elastic region, plastic region, proportional limit, tensile strength, onset of necking, fracture stress.

Consider the tensile stress-strain diagram below. If samples 1 and 2 are identical except that they were tested at different temperatures, which sample was tested at a lower temperature? Note: This question will be marked negatively so consider your answer carefully. A.  Sample 1 B.  Both were tested at the same temperature/ Alby is by die dieselfde temperatuur getoets C.  Sample 2

As a materials engineer in a metal-processing company, you are given a section of metal to heat treat after cold working. You are also able to view the microstructure of the metal before and after heat treatment and characterise its mechanical properties. Which of the following describes what you expect to find, when comparing the properties of the metal after heat treatment to before? Select one or more: a. Increased strength b. Reduced strength □ C. Increased ductility d. Reduced ductility

A ul ? KBIS M 1:11 O photo_2021-0... -> 200 stress 150 (MPa) (00 50 0-2 strain From the tensile stress-strain behavior for the brass specimen d the diamcter is 12-8 mm Calculate the folluding:- 1- The Yield stress. 2- Modulus of elasticity. 3 - The Tensile strength . II

Example: Consider a metal whose strain hardening behavior follows: 25,000 0.25 psi. If an annealed bar of this metal is pulled in a tension test from a starting dia. of 12.7mm to a dia. of 11.5mm (uniform elongation, no friction, no distortion), what is the work per unit volume required? If the bar is reduced by extruding and the deformation efficiency is 70%, what is the extrusion pressure?

No wrong answer please , i could downvote The piece of suture is tested for its stress relaxation properties after cutting 3 cm long sample with a diameter of 1mm. The initial force recorded after stretching 0.1 cm between grips was 5 Newtons. Assume the suture material behave as if it has one relaxation time. The gage length was 1 cm. a. Calculate the initial stress. b. Calculate the initial strain. c. Calculate the modulus of elasticity of the suture if the initial stretching can be considered as linear and elastic. d. Calculate the relaxation time if the force recorded after 10 hours is 4 Newtons.

Problem 2: A catastrophic failure occurred to a 7079-T6 aluminum alloy shaft. The maximum tensile stress was specified as 30% of the yield stress (0₂ = 300 MPa) and the stress ratio R was zero. Post-failure examination found that fatigue crack growth striation started at a depth of 2.0 cm from the surface, and the striation spacing was 1.3 x 10-4 cm. The fatigue-crack growth behavior of the aluminum alloy is given in the right figure. The manufacturer claimed that the part was overloaded by the user, but the user denied the allegation and sued the manufacturer. As a mechanical engineer, what is your verdict based on your calculation? da/dN (μm)/cycle 4 6 8 10 2.5TTTTT 1.0 0.25 Titanium Aluminum 0.05- 10 20 30 ksi Vin 40 60 80 100 • 200 Som 200 T -Steel 80 AK (MN/m2) 400 600 1000 • A533 alloy steel Ni-Mo-V alloy steel A HP 9-4-25 alloy steel 7079-T6 aluminum alloy 5456-H321 aluminum alloy Ti-6 Al-4V titanium alloy L 180 T 600 100 480 460 40 uin./cycle